Ultimate Review PDF

Lesson 1 Lab safety Lab safety rules 1. Never do an experiment without instructions/approval from the teacher. And read all instructions/directions before the start of an experiment. 2. Safety goggles must be worn at all times during experiments. 3. Liquid waste must not be disposed of in the containers provided and not down the sink. 4. Broken glass goes in the broken glass container. 5. Report all accidents to our teacher ASAP. 6. Use only the amount of materials instructed in the instructions. This is because a controlled amount of chemicals can help us reduce the chance of chemical reactions. 7. Never smell or taste chemicals since they may be poisonous. 8. There shouldn’t be horseplay in the lab area as someone could get seriously hurt. 9. Never put out a chemical fire with water since it will spread. We should smother it instead or use a fire extinguisher. 10. Never leave our lab area unattended while a lab is in progress. We should already have all our materials at our workstation before the beginning of the experiment. 11. Clean up all spills and equipment after each lab activity. Our equipment and lab area must be as clean as we found it or cleaner. Lesson 2 Observation and inferences Observation A good question is formed from observations. Observations are formed from using the five senses to gather information such as notes and record facts. 2 type of observations ○ Qualitative Observations which can be made without measurement and can be recorded without the need for numeric values. ○ Quantitative Observations which give data that can be put in terms of a quantity(numeric values) Inference Logical interpretation based upon prior knowledge and experience Based upon observations ⛤ Observation vs inference Observation ○ Based on five sense Sight Smell Touch Taste hearing Inference ○ Based on prior and new knowledge, facts, and opinions. Predictions ○ Guessing what will happen next based on observations. Lesson 3 Particles to solution Particle theory-Explanation of what matter is made of and how it behaves -The particle theory: 1. Matter is made up of tiny particles with space between them. a. Matter=Anything that has a mass and takes up space b. Matter exists in states(Solid, liquid, gas) i. Solids are very compact(Not much space to move around) ii. Liquid have more space but not too much as they still stick together but can move. iii. Gas can move freely in the air bouncing. 2. The particles of a substance move faster as its temperature increases(excited state) a. Increase in temperature happens when we add heat. i. Heat is energy b. When we add energy to particles they move more faster 3. Different substances are made up of different kinds of particles. 4. Particles are in constant random motion. a. The particles in a gas are in continuous, rapid, and random motion. b. The particles travel in straight line paths until collision. The particles then change direction. 5. Particles attract each other. a. Solid objects-High force of attraction b. Liquid objects-Medium force of attraction c. Gas-Low force of attraction Classification of matter Pure substances: Matters that cannot be separated at all by any physical means are PURE. In a pure group there is an element and compound. Elements are only one kind of atom-Such as oxygen and carbon Compounds have 2 or more types of atoms-such as water and salt Mixture substances: Matter that can be separated by physical means is called a mixture. In matter there are two groups, Homogeneous and Heterogeneous. Homogeneous are uniform meaning they become one such as salt water and the atmospheric air. Heterogeneous are clear different objects such as chocolate chip cookies(chocolate chip and cookies) or Pizza(pizza bread, toppings) Lesson 4 Physical and chemical properties Physical properties(Observed by our senses(qualitative) and/or measured by measurement(Quantitative/numbers) Describes the characteristics of a substance that can be observed or measured. ○ For example the the melting point of a substance(degrees/ celsius) Physical properties ○ Colour ○ Lustre(shininess) ○ Optical clarity ○ Brightness ○ Viscosity ○ Hardness ○ Malleability ○ Ductility ○ Electrical conductivity To be more specific ○ Quantitative Property that’s measured and had numeric value Temperature Height Mass ○ Qualitative A property that is not measured and does not have a numerical value Observations made by the 5 senses Colour Odour Taste Texture Sound Physical change A change in which the composition of the substance stays the same. No new substance is formed. Matter changes but no new matter is made. ○ Bending/Breaking/Cutting Material changes form but it isn’t new ○ Change of state Material changes into another state(Water-Ice) ○ Dissolving Sugar in water-sugar still in water Chemical properties(Observed by a chemical reaction with another substance(Describes the ability of a substance to change into a new substance(s)) Flammability ○ How easy something lights on fire Combustibility ○ Rusting-When a metal is exposed to air, it can rust. Chemical change Process where a chemical change occurs. A new substance(s) is formed. ○ Evidence that shows there is a chemical change Light or heat is produced New Odour is created A precipitate forms A formation of a new solid inside a liquid Gas or bubbles are produced An unexpected change in colour Lesson 5 Characteristics of physical properties A physical property that is unique to a substance can be used to identify the substance. Density -We can measure the volume of an object by mass. Density=mass/volume 3 characteristics of physical properties of PURE substances 1. Density a. The ratio of a substance’s mass to its volume Mass b. A measurement of the amount of matter something contains. Weight c. The measurement of the pull of gravity on an object. Volume d. How much space matter occupies e. The amount of space that an object takes up is the object’s volume. f. Standard units are mL and cm^3. Formula for calculating density and manipulating formula Density=Mass/Volume 2. Freezing/Melting point 3. Boiling point Unusual properties of water When lead goes from liquid to solid state it keeps shrinking and occupies less space as it is more dense. Solid water on the other hand takes up more space and is less dense. This causes solid water(ice) to float on liquid water. Water as a solid takes up more space due to the hexagonal structure of the hydrogen bonds. Water groups in 6 to form a hexagon. 1. Freezing point a. Temperature at which a substance turns from a liquid to a solid 2. Melting point a. Temperature at which a solid turns into a liquid. 3. Boiling point a. Temperature at which a substance turns from liquid to gas. Lesson 6 Periodic table of elements Group are vertical(UP AND DOWN) Periods are horizontal(left and right) Period 1’s are special elements Important definitions Elements A pure substance that cannot be broken into a simpler chemical substance by any physical or chemical means. Element symbol An abbreviation for a chemical element. Compound A pure substance composed of two or more different elements What is inside an element’s box What is an atom? The smallest unit of matter What matter is made of Atom is made up of protons, Neutrons and electrons The atomic structure consists of the nucleus in the center and electrons to surround the nucleus via orbiting. Metals vs non-metals Metals Are found on the left side of a periodic table Reveal a metallic sheen when freshly cut. Have metallic properties such as lustre, ductility, malleability. Non-metals Found on the upper right portion of the periodic table. Mostly gasses and dull powdery solids. Metalloids Have properties of both metals and nonmetals. Found at the boundary between metals and nonmetals Lesson 7 Atomic theories What are atoms? Atoms are the smallest form of matter. ○ Matter is anything that takes up space. Everything is made of atoms Atoms are known as the basic building blocks of matter. Theory Scientific theory –An expression of our best understanding of scientific phenomena based on scientific evidence or reasoning. –As technology advances we may need to adjust the theories. Key scientists that aided in the development of the model of the atom. Democritus(400 BC) ○ States: All matter can be divided into smaller and smaller pieces until we reach a single particle. ○ Stated: Atoms are of different sizes, in constant motion, and separated by empty spaces. Aristotle(384-322 BC) ○ Thought that all matter was made up of earth, water, air, and fire. ○ These substances have four specific qualities: dry, wet, cold, and hot. ○ This theory was accepted for almost 2000 years. John Dalton(1807) ○ Proposed that: All matter is made of small indivisible particles called atoms. All atoms of an element are identical Atoms are rearranged to form new substances in chemical reactions, but are never created or destroyed. ○ Dalton’s billiard ball model wasn’t able to explain negative and positive charges. Thomson(1897) ○ Experiment with a cathode ray tube. ○ Manipulated the stream of particles with positively and negatively charged objects Found that: Atoms contain negatively charged electrons. Since atoms were and are neutral, the rest of the atom must be a positively charged sphere. The electrons are distributed evenly throughout the atoms. ○ The cathode ray tube experiment was called the Plum Pudding model. Rutherford(1909) ○ Through his gold foil experiment, Rutherford proposed that: The center(Nucleus) is made up of positively charged particles(protons). The Nucleus makes up most of the mass but takes up little space(mostly empty space). Chadwick(1932) ○ Chadwick discovered a particle that could smash atoms but had no charge(Neutrons). ○ Chadwick proposed that: Nucleus is made up of protons and neutrons. A neutron has the same mass as a proton. Electrons circle rapidly around the nucleus. Neutral atoms have the same amount of electrons and protons. Neils Bohr ○ Passed light made from different gasses through a prism. ○ Light is given off when an electron moves to a lower orbit. ○ Therefore Nelis Bohr proposed that: Electrons orbit the nucleus at different levels(shells, orbits). When an electron gains energy it goes up an orbit and when it loses energy it goes down an orbit. Lesson 8 Periodic table explained Atomic number The number represents the number of protons in the nucleus of the element. Number of protons is equivalent to the number of electrons. Mass Number Mass Number=Number of protons+number of neutrons. Isotopes An atom with the same number of protons but a different number of neutrons. (Atoms with different atomic masses of the same element are isotopes of each other). 1. Lithium as an example a. LI-6 vs Li-7 i. Both isotopes are stable and exist in nature but Li-7 is more common, BUT there are small amounts of naturally occurring Lithium that have 3 protons and 3 neutrons. This is an isotope since Lithium normally has 4 neutrons not 3). Number of neutrons= Atomic mass – Atomic number The most outer layer of the shell is known as the VALENCE SHELL where the electrons on there are called VALENCE ELECTRONS. 1. Group 1 has 1 Valence electron 2. Group 2 has 2 valence electrons 3. Group 13 has 3 valence electrons 4. Group 14 have 4 valence electrons 5. Group 15 has 5 valence electrons 6. Group 16 has 6 valence electrons 7. Group 17 has 7 valence electrons 8. Group 8 has 8 valence electrons. In Shell Number 1 there are a maximum of 2 electrons and in shells 2, 3, and 4 there are 8 maximum electrons. When drawing a Bohr Rutherford diagram the first step is to write it in ↑ → ↓ ← this order. REMEMBER THE FIRST 20 ELEMENTS AND BE ABLE TO DRAW THEM. Lesson 9 Putting atoms together Molecules Two or more atoms of the same or different elements that are chemically joined together in a unit. FOR EXAMPLE: Our air is composed of 80% Nitrogen molecules, 20% oxygen molecules and small amounts of water molecules and carbon dioxide molecules. Molecule types Formed by sharing electrons Molecular elements and Molecular compounds Formed ionic bonds by giving electrons Ionic compounds Chemical bonding rules of electrons and atoms. Number 1. Electrons can move and jump from atom to atom. Metals give electrons to nonmetals. Number 2. Atoms want to have a full outer shell of electrons. Because having a full outer shell makes them more stable. Number 3. Electrons will move or be shared so that atoms will gain a full outer shell. Covalent and Ionic bonds. Covalent Bonds Non-metal+Non-metal ○ Share valence electrons so that they have full valence shells. Molecular elements are a molecule that consists of atoms of the same elements(Diatomic molecules) HOFBrINCI Hydrogen=H=H2 Oxygen=O=O2 Fluorine=F=F2 Bromine=Br=Br2 Iodine=I=I2 Nitrogen=N=N2 Chlorine=CI=CI2 Molecular compounds A molecule that consists of 2 or more different elements which are held by covalent bonds. Ionic Compounds A compound made up of positive and negative ions. Ionic bonds Metal+Non-metal ○ Metal gives its valence electrons to a non-metal so that they both have a full valence shell. Makes the metal positive and the non-metal negative. What are ions? Ions are a particle or element that has a negative or positive charge. We can tell the ions of an elements on the periodic table by looking at the top right corner of an element which tells us if the element has more than one or lesser ionic charges. Why do elements on the left side of the periodic table have plus and elements on the right side have a negative charge? An ion forms when an atom loses or gains one or more electrons. Net charge –If an atom LOSES an electron, it has one or more protons than electrons so it becomes more positive. –If an atom GAINS an electron, it has one more electron than protons, so it becomes more negative. Cations(Cat-IONS) Positively charged for example Na+. Same name as element for example Sodium Ion Anions(An-IONS) Negatively charged for example Br- Add Ide to the stem of the name for example oxygen becomes oxide ion. Lesson 10 How atoms combine THREE CHEMICAL BONDING RULES FOR ELECTRONS AND ATOMS 1. Electrons can move and jump from atom to atom. 2. Atoms want to have a full outer shell of electrons. 3. Electrons will move or be shared so that atoms will gain a full outer shell. Why do atoms combine? Atoms combine for the sole purpose of becoming more stable. Noble gases ○ Column 18(AKA group 8A) are the most stable They have the maximum amount of electron in their outer shell ○ Helium 2( period 1), All other 8(period 2 and 3) or 18 (period 4) Elements with incomplete outside shells combine with other elements to obtain the maximum number of electrons. Atoms can become more stable by gaining, losing, or sharing electrons Three types of combinations 1. Metals and metals a. Creates alloys b. Solid solution c. Not an actual compound 2. Metal and nonmetals a. Create ionic compounds with ionic bonds 3. Nonmetal and nonmetals a. Create molecular compounds b. Elements with covalent bonds. METALS AND METALS An alloy ○ Solid solution ○ Not a compound ○ A mixture of 2 hot liquid metals that solidify. ○ Help soft metal gain strength. metals + non-metals Ionic compounds are made up of oppositely charged ions(and polyatomic ions) Attracted to each other. Metals lose electrons and become CATIONS(positively charged) Non-metals gain Electrons and become ANIONS(Negatively charged) Non-Metals+Non-metals ○ Covalent bonds formed when 2 or more nonmetals share electrons. ○ This sharing of electrons give the atoms the “illusion” that they have a complete outer shell. Sharing electrons When it comes to sharing electrons with one or more elements to form full outer shells. The electron shared counts for both elements' outer shell as elements can share multiple electrons. Lesson 1 What are the four spheres of the earth? Atmosphere Atmosphere composition ○ 78% Nitrogen ○ 21%Oxygen ○ 1%argon, water vapor, and CO2 Atmosphere is the layer of gasses around the earth Moderates earth surface temperature Blocks incoming solar radiation Most of earth’s species depend on the atmosphere. Lithosphere Earth’s solid outer layer Contains earth's rocks and minerals 50-150km Hydrosphere All the earth's water in solid, liquid, and gas state 97% of earth’s water is in the ocean. Biosphere The zone around the earth where life can exist Ecosystem All the living organisms and the physical and chemical environment Composed of populations of plants and animals and their biotic and abiotic factors Can be as large as a forest or lake or as small as a rotting log A community of differing species interact within an ecosystem Organisms Individual living things Tremendously diverse ○ 1.3 million species have been formally identified and described on Earth! ○ Estimated 8.7 million species that live on Earth All organisms have the same basic needs - energy and matter ○ Need to get basic needs from the environment ○ Organisms are in an open system with their environment Abiotic and Biotic factors Abiotic factor ○ Non-living and chemical compositions of an ecosystem Biotic factor ○ The living and features related to the living organisms. ○ Remember - If it was once a living thing, or made from a living thing, it is a biotic factor and an abiotic factor (has qualities of both) Lesson 2-3 Photosynthesis The process in which the sun’s energy is converted into chemical energy Glucose formula—C6H12O6 Eutrophication 1. Nutrients overload in the water(Algae bloom) 2. Algae die. 3. Bacteria decomposes the dead algae and then uses up all the oxygen in the process Cellular respiration The process where sugar and oxygen is converted into carbon dioxide and water to provide enough energy for the cell. Consumer vs producer Consumer ○ An organism that obtains its energy from other organisms. Producer ○ An organism that takes the sun’s energy and makes their own food. Ecological Niche the function a species serves in its ecosystem, including what it eats, what eats it, and how it behaves Types of eaters ○ Herbivores Eats only plants ○ Carnivores Eats other animals ○ Omnivore Eats both animals and plants ○ Scavenger Animals that feed on the remains of other organisms Lesson 4 Climate change Climate change is the process where there is a long term shift and alteration in the global or regional climate pattern. Climate change is mainly and often caused by human activities such as the burning of fossil fuels, deforestation, and industrial processes. These human activities produce greenhouse gasses into the atmosphere. The greenhouse then traps the heat from the sun and contributes to the greenhouse effect. Indicators of climate change Rising temperature Melting ice Rising sea level Changing weather patterns Impacts of climate change on ecosystems Biodiversity loss Change in species distribution Ocean acidification and coral loss Changes in ecosystem services Solutions to climate change Renewable energy Saving energy Ecosystem management Green transportation Lesson5 Abiotic and biotic influences Tolerance range ○ The abiotic conditions within which a species can survive Terrestrial ecosystems and limiting factors Biotic factors ○ Competition–individuals fight for the same resource ○ Predation–Individuals feed on another organism(predator kill and eat prey) ○ Mutualism–individuals benefit from each other ○ Parasitism–Individuals live in or on and feed on a host ○ Commensalism–one individual benefits and the other neither benefits or is harmed Carrying Capacity ○ Maximum population size of a particular species that a given ecosystem can sustain Lesson 6 Habitat fragmentation ○ Dividing regions into smaller parcels or fragments ○ Habitat loss and fragmentation is the second to the most serious threat to the sustainability of ecosystems One large habitat is better than multiple little habitats Connecting smaller habitats by corridors to permit migration and interbreeding of different popu;ation. Wetlands ○ An area of land that is saturated with water either permanently or seasonally. Loss of wetlands and aquatic ecosystems ○ Human activities also threaten aquatic ecosystems. ○ Natural wetlands are flat and often have deep, nutrient rich soil with an abundant water supply Lesson 7 Forestry practices Clear-cutting ○ Removal of all or most trees in an area ○ Allows for easy transportation of trees to the mill ○ New patch of trees will be composed of even aged trees ○ Areas are subject to erosion Shelterwood cutting ○ First cut removes canopy, diseased trees and unwanted species. ○ Second cut is done a decade or more later Canopy trees will be removed but some mature trees are left behind. ○ Third cut done another decade or more later. Remaining mature trees leave behind a stand of young similar aged trees ○ Designed to avoid clear cutting Selective cutting ○ Foresters periodically harvest selected trees ○ Maintains an uneven aged system ○ Expensive ○ Usually performed on private woodlands Supply and demand ○ Harmful when applied to natural resources ○ Overharvesting Mahogany Threatens the sustainability of forest ecosystems Tropical forest Do not grow back as quickly as temperate and boreal forest(TAIGA) Wildlife management ○ Stewardship Taking responsibility for managing and protecting the environment Lesson 8 Fertile soil A dark rich soil referred to as loam ○ 40% sand ○ 40% silt ○ 20% clay Has a good quantity of humus ○ Humus is the biotic remain of plants and animals Many good bacteria to help with the decomposition of plant material Managing soil nutrients Most important nutrients ○ NITROGEN PHOSPHORUS POTASSIUM If a farmer plants the crops for several years in a row certain nutrients will be removed from the soil ○ Farmers then do crop rotation or let the field lie unused. Fertilizers Natural ○ Plant nutrients that have been obtained from natural sources and have not been chemically altered by humans Animal manure(poop) Mulch(Decomposed plant material) Synthetic ○ Fertilizers manufactured using chemical processes Environmental impacts of fertilizers ○ Leaching Process by which nutrients are removed from the soil as water passes through it. Nitrogen compounds filter down into the groundwater and can contaminate drinking water. ○ Algae Bloom Fertilizers allow too much algae(tiny plants) to grow in water Remove oxygen from lakes and ponds Advantage of synthetic and natural fertilizer Synthetic fertilizers ○ Nutrients are released too quickly ○ Amounts of nutrients can be precisely measured ○ Relatively easy to apply Natural fertilizers ○ Less danger of overflowing ○ Release nutrients slowly ○ Can improve soil structure ○ Benefits soil microorganisms and nutrient cycling. Disadvantage of synthetic and natural fertilizer Synthetic fertilizers ○ Production is energy intensive ○ Cause water pollution ○ Nutrients lost from soil through leaching ○ Can cause an imbalance in soil chemistry and upset the balance of soil microorganisms Natural fertilizers ○ Low concentration of nutrients ○ Release of nutrients may be slower than desired ○ Not easy to measure the quantity of nutrients ○ May be more difficult to apply Controlling the flow of water Irrigation Maintains ideal growing conditions for crops Allows us to use land that would be too dry Removes water from nearby rivers can make rivers run dry No chemical substance Re-allocation of water Drainage Drainage pipes have to be installed to remove the over abundance of water Alternate farming practice These practices help farmers to protect their farmland Three approaches to reduce the impacts of agricultural practices 1. No tillage farming a. Helps retain soil nutrients, reduces soil compaction and water loss and improves soil quality b. Sometimes requires greater pesticides use because weed population are no longer controlled by plowing them under 2. Crop rotation a. Rotate or change the crops they plant on a certain area of land on a regular basis b. Farmers can reduce their use of land on a regular basis by rotating crops 3. Crop selection a. Grow crops that are better suited to the local growing conditions Pesticides Helped farmers reduce crop damage from pests and increase food production Help control the population of biting insects that spread disease. Benefit can result in more food and better health for some. Pesticides use has a number of environmental costs Non target species-killing wrong organisms When using broad spectrum pesticide potentially beneficial organisms could be killed DDT is a well known bad pesticide because it doesn’t break down easily and keeps its lethal characteristics for a long time. Bioaccumulation The concentration of substance such as pesticide in the body of an organism Biomagnification/Bioamplification Increases concentration of a substance such as pesticide as it move higher up the food web Pesticide resistance When pesticides are used for a long time, some pest species may become resistant to the pesticide Organic farming The system of agriculture that relies on non-synthetic pesticides and fertilizers Biological control ○ Predatory insects eat on and infect prey species Altered timing ○ Better timing of planting and harvesting can avoid peak pest population Crop rotation and mixed planting ○ When farmers do not grow plants and crops in the same place annually then pests population cannot accumulate Baiting pests ○ Pheromone baits can be used to confuse some mating insects. Advantage and disadvantage of organic farming Advantage of organic farming Farmers can reduce production costs due to the loss of need to buy expensive chemicals and fertilizers. Healthier farm workers Long term use can protect the environment and save energy. Fewer residues in food. Can slow down global warming More animals and plants can live in the same place in a natural way(biodiversity) Pollution of groundwater is stopped Disadvantage Organic food is more expensive because farmers do not get as much out of their land as conventional farmers do. ○ Organic products may cost up to 40% more. Production costs are higher due to farmers needing more manpower Marketing and distribution is not efficient because organic food is produced in smaller amounts Food illness may occur more due to no pesticides to stop it Organic farming doesn't produce enough food at a fast enough speed that there could be starvation. Lesson 1:Static electricity Goals: Explain the process by which an object is charged Explain the law of electric charges 3 Subatomic particles ○ Outer layer=Electron ○ Inner layer has Neutron and Proton When an object is positively charged, there will be a LOSS OF ELECTRONS. ○ Therefore the object will have a positive charge ○ Materials such as hair, wool, fur, glass, leather… tend to LOSE electrons. When an object has a negative charge, there will be a GAIN OF ELECTRONS. ○ Materials such as wood, amber, rubber, polyester, saran wrap… tend to GAIN electrons Neutral Charged Object - has equal number of electrons and protons Positive Charged Object - has fewer electrons than protons Negative Charged Object - has more electrons than protons What is Static electricity? Static Electricity = imbalance of electric charge on the surface of an object. When static charges build up on an object, it can cause an object that is charged or neutral to be attracted or repelled by it. Methods for electron transfer: Friction–Rubbing two neutral materials together. Conduction–A charged object touches a neutral object to transfer electrons Induction–Charging an object without touching the other object. Law of electric charge: The force exerted by an object with an electric charge can be a force of attractions or a force of repulsion. When we bring a charged object towards a neutral object, an included charge separation will create a shift of position of electrons in a neutral object that occurs when a charged object is brought near it. Examples of practical applications using static charge Electrostatic paint spraying Powder coating Laser printing Lesson 2:Charging by contact Goals: Explain two neutral objects that can be charged by contact Explain through diagrams, the flow of charge to and through a grounded object Explain how charges are used in appliances such as electrostatic dusters and precipitators Two main methods for charging by contact: 1. Friction a. Two different neutral objects rub or touch each other. b. One object becomes positive and the other becomes negative. 2. Conduction a. Two charged objects contact and electrons move from one object to another. Electrostatic series: A list that ranks the ability for materials to gain or lose electrons. Used to make predictions on what charge the objects will have after they come into contact with each other After choosing two objects from the series, we rub them together. The object Above the other object will become positive and the Lower object will be negative. For example: If we rub wool and ebonite then wool would become a positively charged object while ebonite becomes a negatively charged object. Anytime a positively charged object contacts a neutral object, it will make the neutral object positive. Sum up conduction: Negatively charged objects that touch a neutral object ○ Negative charges move from the charged object towards the neutral object to balance the subatomic particles. The neutral objects then become negatively charged. Positively charged objects that touch a neutral objects ○ The negative charges on neutral objects will move towards the charged object since it is positively charged, it requires a negative charge. Therefore the neutral object then becomes a positively charged object. To sum up the summary: The neutral object will get the same charge as the charged object after conduction. What is electric discharge? Electric discharge is the rapid transfer of electrons from one object towards another to counter the charge imbalance. Electrons always move from the object that is more negative towards the object that is less negative to balance the electron mass. Can be visible as a spark. If the electric discharge is big enough it can hurt and cause a burn on our skin, or damage circuits in electronics. Grounding Grounding is a process where an object removes the excess charge by transferring electrons between objects such as the earth. Charged objects become Neutral after touching a grounded object. Lightning Lightning is the visible and dramatic electric discharge between clouds or from the cloud to the earth. The excessive electrons on the bottom of the cloud then goes to the earth to try to balance the subatomic mass of the cloud and the earth. The lightning causes a charge imbalance, and negative electrons can be transferred if large enough. Lightning rods Lightning rods are placed on top of buildings to provide a safe path for lightning to lead the lightning to the ground. Lightning strikes the rod and is transferred to the ground via conductive wires. Lesson 3:Charging by induction Goals: Draw and name the parts of a circuit Can annotate a diagram showing the direction of electron flow from a battery. Charging by induction is a process of charging an object without direct contact between the object and charged object. During charging by induction a charged object is brought near a neutral object which causes the charges in the neutral object to move around. ○ In the end one end of an object is positively charged, while the other end becomes negatively charged. The neutral object can then be temporarily charged by grounding or by removing the charged object. Charging objects temporarily by Induction ○ When a charged object is brought near a neutral object, the electrons shift in position, which then causes uneven distribution of charges “Temporarily”. ○ When we move the charged object away, electrons move back to their original position. Charging objects permanently by induction ○ Objects can be permanently charged by induction by grounding the object. This results in two objects with opposite charges. Objects that give the charge stays the same while objects which were charged will have an opposite charge Charging Method Object doing the Object getting Explanation of the charging charged movement of charge Charging by Positive Electrons in the Electrons move induction object will move closer to the object (temporary) CLOSE to the because they are object attracted, but then move back to their original positions Charging by Negative Electrons in the Electrons move as induction object will move far away from the (temporary) away from the negative charge as object doing the possible. The charging; object negative object and will be attracted the neutral object are attracted (induced charge separation) Charging Method Object doing the Object getting Explanation of the charging charged movement of charge Charging by Positive Becomes negative Electrons enter the induction sphere from the (permanent) ground because they are attracted to the positive object Charging by Negative Becomes positive Electrons enter the induction ground from the (permanent) sphere because they want to get away from the negative charge of the object Technological applications of charging by induction Electrostatic lifting apparatus ○ Used in forensic science to create a copy of the footprint to be analyzed Special film/foil is placed over the footprint - black side faced down Film is electrostatically charged Dust and dirt particles from the footprint are attracted to the black side of the film, and the particles “jump” onto the black film Conductor is a material that allows electrons to move through it. Insulators are a material that doesn’t allow the movement of electrons Examples One example of technological advancements that have taken advantage of charging by induction. Laser printers: Positively charged photoconductor (drum). When laser light hits an area of the drum, that area turns negative. The drum rolls across positive toner (particles). The drum transfers the toner to the paper (negative). Lesson 4:Current electricity and currents Current electricity The controlled flow of electrons in a circuit Electric circuit A continuous path of electrons to flow through. Parts of an electrical circuit. 1. Conducting wire a. A material that conducts electricity and can transfer the electrons from the source to the load. 2. Switch a. A mini contraption that can stop and continue the flow of electrons. 3. Load a. Part of an electrical circuit that converts electrical energy into other forms of energy. 4. Source a. An energy source that supplies the load. Electrons flow continuously in a closed circuit. An open circuit is a circuit with an opening somewhere along the wire or part of the circuit. Lesson 5:Generating currents Goal: Explain the basic concepts of creating electricity Direct currents The flow of electrons in one direction. One common analogy is the water tank. The water goes out one hole. Alternating currents A flow of electrons that alternates in direction in an electric circuit. Voltage The pressure that is needed to move an object. Which in this topic is electrons. Why AC? Alternating currents allow for better electric transfer with lower energy loss. Energy flows continuously throughout a power plant. Transformer is used to allow power to be transmitted at higher voltages. POWER SOURCES Hydroelectricity(the force of falling water which moves a turbine which builds up energy). ○ Pros Renewable Does not pollute the atmosphere. ○ Cons Disrupts large areas of land. Disrupts the migration of fish. Dying trees nearby may release toxins. Can only set up tidal plants in coastal areas. ○ Turn the energy of natural rise and fall of tides into electricity. ○ During high tide the water will flow past the tidal barrage. ○ Sluice gates can shut to control the tide going out. Which aids in generating more electricity. Fossil fuels ○ Pros Coal can be found in many places as it is made of dead organisms. ○ Cons Produces greenhouse gasses. Non-renewable. Nuclear power(A radioactive form of uranium decomposes and releases energy. ○ Pros Uranium rods last a long time. Little greenhouse gasses are released. Have a “safe record”. ○ Cons Uranium rods remain radioactive for thousands of years. Meltdowns can release radiation which can have negative impacts. Non-renewable. Biomass(organic material is burnt to heat water and spin turbines. ○ Pros Sustainable Keeps a lot of biodegradable waste out of landfills. ○ Cons Although much smaller amounts, there is still CO2 released in the air. Geothermal ○ Pros No CO2 Not radioactive Cheap ○ Cons Only found in certain areas. Wind power ○ Pros Clean energy Renewable ○ Cons Inconsistent Solar energy(Photovoltaic cells create flows of electrons from the sunlight rays). ○ Pros Clean energy Renewable energy ○ Cons Panels can be expensive Cannot produce enough energy for homes in northern climates. Lesson 6:Power efficiency and cost calculations Goal: Recall the definition of the units for currents(ampere), voltage (volts) and power(watts). Convert between the standard units for measuring energy to kilo(basex1000), mega(basex1,000,000), and giga(basex1,000,000,000). Can recall and apply the formula for calculating cost and efficiency Quick guide Kilo=basex1000 Mega=basex1,000,000 Giga=basex1,000,000,000 To go from small to large we divide. To go from large to small we multiply. Electrical power The rate at which electrical energy is produced or consumed. 1W=1J/s( joules per second) Electrical power cost For example a 60W incandescent light bulb vs a 15 W Fluorescent light. ○ Produces the same amount of light. 60W uses more energy compared to 15W because the energy is wasted on heat and other forms or energy output. Efficiency A comparison of the energy output with the energy supplied. A computer in sleep mode is x30 more efficient than one that is on 24/7. About 90/100 of electricity that runs an incandescent light bulb turns to heat instead of light. Light emitting diodes(LED) use less energy and last longer. To calculate the efficiency of a device Formula: %efficiency= % energy out/ % energy in X 100% Energy out:the useful energy the device puts out to do a task. Energy in: How much energy a device requires. Example: 1. A toaster oven uses 1200 J of energy to produce 850 J of thermal energy. Calculate the % efficiency? 850 J/ 1200 J X 100( DO NOT PUT % in calculator or else it will be wrong by divide 100) or if we do put % X the answer by 100. 2. A light bulb uses 100 J of electrical energy and produces 35 J of light energy. Calculate the percent efficiency of the light bulb? 35 J/ 100 J X 100%=35% Calculating cost of electricity Cost to operate = Power used X time X cost of electricity. Power used -> Watts, kW, MW Time->sec,min,hours KILOWATT HOUR SI units used to measure electrical energy usage. 1 kilowatt for 1 hour MW=megawatt; 1,000,000 watts 1kWH=3.6Million joules What is joule? Energy dissipated as heat MUST KNOW K-15 T-8 C-9 A-10 K -Determine the electric charge when given a diagram of an atomic structure(atomic structure=Bohr rutherford diagram in chem) -Using the electrostatic series to predict the charge of objects when rubbed. -Determining the charge of an object when electron transfer occurs( such as induction, friction, conduction) -Examples of renewable and nonrenewable energy sources. -The energy unit and the conversion (example. 1kW=1000W, 1W=1j/s) -Draw labeled diagrams connected in series(entire circuit) Explain how the light bulb turns on For example explaining in a circuit why if the switch is open it cannot ignite the light. Conductors and insulators( example and why they are good conductors and insulators.) Thinking -Calculation (cost, kWH) 2 calc questions Include equation Show our work All units in the final answer. Communication Ways of charging(friction, charging, induction) By looking at an image we can explain the way of charging 3 questions-Draw diagrams to explain charging methods(scenario will be given)+grounding devices Application -Renewable energy and non renewable energy sources Describe how energy is converted into electricity Pros and cons -Friction (making predictions about an object)(2 different materials rub against each other and we make observation and inferences) -Conductors and insulators(example of each) BRING A RULER AND CALCULATOR Given: % efficiency equation Cost equation Electrostatic series table Lesson 7:Circuits and currents Goal: Draw a series and parallel circuit Can connect and draw an ammeter correctly to a circuit. Electric circuit A continuous path in which electrons can flow A circuit has 4 main parts 1. Conducting wire 2. Source 3. Switch 4. Load 1. Conducting wire A conductor to join all parts of the circuit 2. Source A source of electrical energy 3. Switch Controls the current flow in an electric circuit by opening and closing. 4. Load Part of an electrical circuit that converts electrical energy into other form of energy Circuit diagram ○ A way of drawing an electrical circuit using standard symbols. Series circuit ○ A circuit in which the loads are connected end to end so that there is only one path for electrons to flow. Parallel circuit ○ A circuit in which the loads are connected by branches so that there are 2 or more paths for electrons to flow. Electric current ○ Symbol for current is I ○ A measure of the rate of the electron flow past a given point point in a circuit ○ Measured in amperes(A) ○ Ammeter A device used to measure electric current. Ammeter must be connected in series with the load. ○ Coulomb A quantity of electric charge The movement of electric charge past a point is called current in an electric circuit. For example a flashlight bulb that has a current of one ampere will pass one coulomb of charge every second. Lesson 8:Potential difference and resistance Goals: Draw a circuit diagram State the proper reading that a voltmeter should show after analyzing a circuit diagram. Can measure/evaluate the resistance of a circuit Potential difference- Voltage The difference in electric potential energy is measured at 2 different points which are measured in volts(V). The potential difference is voltage. Electrons leave the negative(-ve) terminal with electrical potential energy. When electrons return to the positive(+ve) terminal of the cell they have less potential energy. Once inside the cell the chemical reaction is “re-energizing” the electrons. Voltage is the energy or push of the current in a circuit. Measuring potential difference A voltmeter measures the relative voltage between 2 points(after the positive terminal of a cell and right before the negative terminal). A voltmeter has to be connected ACROSS THE LOAD OR ACROSS THE BATTERY TERMINALS. This means that potential difference is measured in parallel. Vocab: Battery ○ Gives energy or the push that electrons need in order to move through the circuit. Loads ○ Uses the energy in circuits. Resistors ○ A load is a resistor since it will use the current that flows through itself. It will slow down the flow of electrons. Current ○ The flow of electrons in a circuit. ○ Measured in Amperes(Amps) ○ The symbol for current is I. ○ An ammeter will measure it in a circuit. ○ Connected in series in the circuit. Voltage ○ The energy or push of the current in a circuit. ○ Measured in volts. ○ The symbol for voltage is V. ○ A voltmeter measures voltage in a circuit. ○ Connected in parallel to a load to measure. Calculating potential difference We can calculate the amount of voltage(potential difference) across two terminals of a battery, or across a load. Voltage conversions mV=millivolts=0.001 volts V-volts=1 volt KV=kilovolt=1000 volts MV=megavolt=1,000,000 volts GV=gigavolt=1,000,000,000 volts Potential difference for voltage formula 1V=1J/1C Lesson 8.2:Potential difference and resistance Goals: Draw a circuit diagram State the proper reading that a voltmeter should show after analyzing a circuit diagram. Can measure/evaluate the resistance of a circuit Electrical resistance The ability of a material to oppose the flow of electric current which is measured in ohms. Ω There are 4 different factors that can affect the resistance: 1. Type of material a. Materials that are good conductors of electricity have low resistance. b. Materials that are good insulators have high resistance. c. Conductivity tells us how well the electrons move freely through a material. 2. Cross sectional area a. Cut through a wire. The diameter of the cross-section tells us how thick a wire is. b. Thicker wires have a low internal resistance. c. Thinner wires have high internal resistance. d. The thinner the wire, the more difficulty the electrons have to “squeeze through”. 3. Length a. A longer wire has higher resistance than a shorter wire b. Electrons have to travel through more material. 4. Temperature a. Electrons bump into atoms as they move. b. As a material heats up, the atoms gain energy and begin to bump into each other and vibrate. c. Greater vibration causes more collisions and therefore more resistance. d. Many devices use resistance to create heat. Measuring resistance An ohmmeter is used to measure resistance. An ohmmeter must be placed across the load( just like a voltmeter.) Resistors in circuits Resistor:a device that reduces the flow of an electric circuit. Dimmer switches often have resistors called variable resistors. The greater the resistance the dimmer the light. What slows down the current flow of electrons in a circuit. Measured in ohms. The symbol of resistance is Ω An ohmmeter measures the resistance in a circuit Connected in parallel to measure. Lesson 9: Ohm’s law review and how series and parallel circuits differ Goals: I will be successful when I can compare and contrast the following 1. Current through loads in series 2. Voltage across loads in series 3. Current through loads in parallel 4. Voltage across loads in parallel The relationship between current and voltage: If we increase the current we will then see a direct increase in voltage. If we graph our results, we will see a linear relationship between voltage and current. This is Ohm’s law( R= V/I) I=CURRENT R=RESISTANCE Class question: V=0.11 A* 1100 V=121V Therefore the potential difference across the light bulb is 121v ANSWERING FORMAT STEP 1: Write down the equation for example if it is a Then substitute the numbers in with units. Then write the final answer with units and then statements. Current through load in series: Circuits with on load is different compared to those with 2 loads This is a result of 2 loads making greater resistance. Voltage across loads in series When 2 identical loads are connected in a series, the loads share the voltage with each other. Since the battery can only supply a finite amount of potential energy. When the electron goes through the lamps then only half of the potential energy is used. When we add more light bulbs to a circuit then it dimms. Formula for calculation the potential difference across a series circuit with identical loads. ○ V load= V Source/#of loads Current through loads in parallel In parallel circuits electrons have different paths to follow. The electrons flowing in the path are less in than origins;. The current splits depending on the resistance of each load(more resistance=less current) Calculating current in parallel circuit with multiple loads Step 1: Use ohm’s law equation which is I=V/Rt Step 2: After getting the current do i load=i source/# of loads CONVERSATION ASSESSMENT: Know how to: Make parallel and series circuits Know where to connect the ammeter and the voltmeter Measure the current/voltage Calculate resistance using the current and voltage Impact of the number of loads on the current and generate brightness Impact of the type of circuit on the loads(brightness) Draw and label circuit using symbols Lesson 1 The night sky Astronomy: The branch of science that studies objects beyond earth. Celestial objects: Any object that exists in space for example the sun or moon Universe: Everything that exists, including all energy, matter, and space Stars: Massive celestial body composed of hot gas that radiates large amounts of energy. Held together by its own gravity. Stars are luminous (produce and emit light) There are billions of stars, many which cannot be seen with the unaided eye. Our systems star: The sun Compared to other stars, the sun is average in size. Has 340,000 times the mass of the earth (3.4 X 105) Has 1, 300, 000 times the volume of the earth. (1.3 X 106). Sun appears brighter than other stars due to the distance of the sun to the earth which is about 1.5 X 106 km away. And the closest star besides the sun is 4.3 x 1013 km away. Planets: A large, round celestial object that travels around a star. In our solar system there are 8 planets travelling around the sun. Each planet has different size compositions, atmospheres, and lengths of day and year. Terrestrial planets: the first 4 planets that are closest to the sun and have similar hard rocky surfaces of the earth.(Mercury, Venus, Earth, Mars) Gas Giants: The next 4 planets are composed mostly of gasses and liquids.(Jupiter, saturn, Uranus, Neptune) Dwarf planet: Pluto Our planet: Earth Earth is the third planet from the sun and the fifth largest in the solar system. Earth is in constant motion. Different from other planets because it has a variety of life forms(humans, animals, etc) and large quantities of water. Solar system: The sun and all the objects that travel around it Moons: A celestial object that travels around a planet or dwarf planet on a closed path. Orbit: The closed path of a celestial object as it travels around a larger celestial object. Earth’s composition: The moon. The moon is earth’s only natural satellite. Non-luminous but we see it because it reflects sunlight. Moon is small compared to planets. Diameter is 4 times smaller compared to earth. Appears larger because of its closer proximity. Earth’s moon is about 384, 000 km away from earth. Lesson 2 The sun The sun’s radiation. 1. Incoming solar energy a. Reflected by atmosphere 6% b. Reflected by clouds 20% c. Reflected from earth surface 4% d. 16% absorbed by atmosphere e. 3% absorbed by clouds f. 51% absorbed by land and Ocean EM Spectrum Electromagnetic spectrum The range of wavelengths of electromagnetic radiation, extending from radio waves to gamma rays and visible light. What EM radiation does the sun radiate: 1. UV radiation 2. Visible light 3. Infrared radiation Structure of the sun The core is the hottest part of the Sun at 15 000 000 °C. The photosphere is the surface of the Sun at 5500 °C. The chromosphere is like the Sun’s atmosphere at 60 000 °C. Composed of many layers of gas. Core is at the centre where high pressure and temperature cause particles to collide and join together called NUCLEAR FUSION. These reactions make the core of the sun the hottest part of the sun. Corona: Outer atmosphere of the sun, it is less brighter than the photosphere (1-3 million degrees celsius) Sun spots: Temporary phenomena on the photosphere of the sun that appear visibly as dark spots compared to surrounding regions. Cooler areas visible in the sun’s photosphere. Caused by disturbance in the sun’s magnetic field. Largest sunspot was 1.8 X 10^10 km2. Solar flare: Gases and charged particles expelled above an active sunspot. Solar Prominences: Low energy gas erupts from the sun’s surface that extends thousands of kilometres into space. Solar winds: Particles such as protons and electrons that are ejected from the sun. The earth’s magnetic field and atmosphere help protect us from spikes in EM radiation and particles. As the particles follow the contours of the magnetic field they ionize the upper levels of the atmosphere which in turn create auroras. Communication disruption: Solar winds(particles) can disrupt communication satellites and even knock out power grids if severe enough. The sun releases charged particles. Aurora borealis: A display of shifting colors in the northern sky caused by solar particles colliding with matter in the earth’s upper atmosphere. Lesson 3 Motion of the moon Earth’s Revolution: Elliptical orbit: As earth spins on its axis, it also rotates around the sun. The distance of each planet from the sun changes as it orbits. Orbital radius: The average distance between an object in the solar system and the sun. Earth is closest to the sun on January 3 and farthest from the sun on July 4. Planets farther away from the sun take longer to orbit because they have a larger orbital path. Motion of the moon: The moon rotates on its axis. The same side of the moon is always facing the earth. It rotates on its axis in the same time it takes to complete one revolution of earth. Moon is actually very fast in motion but it keeps the moon where it is due to the earth’s gravitational pull which counters the moon's own will to leave the earth’s gravitational pull. 8 PHASES OF THE MOON: One revolution around the earth takes about 27 days, 7 hours, and 43 minutes. Solar eclipse: When the moon is aligned between earth and the sun. During a total eclipse, only the sun’s corona is visible. Lunar eclipse: Occurs when the earth is positioned between the sun and the moon Can be seen anywhere on earth. Tides: The alternate rising and falling of the surface of large bodies of water. This is caused by the interaction between earth, the moon, and the sun. The moon’s gravitational force pulled earth and its oceans towards it. Aas earth is pulled towards the moon, a bulge occurs on the opposite side of the earth. Spring tides: Occurs when the sun, the earth, and the moon are all aligned. Combined gravitational force produces very high tides. Neap tides: Occurs when the sun and the moon are perpendicular to each other (during quarter phases) Forms very weak tides Lesson 4 Great distances(Conversion) Just look at the slides 🙁 Lesson 5 Life cycle of stars The life cycle of stars All stars have a life cycle: a beginning, middle and end. The life of a star could last billions of years Our sun is almost 5 billions years old and not yet near end of its life cycle Process of life of a star 1. Stellar Nebula a. Stars begin as a nebula b. A massive cloud of gas and dust c. Consists of Hydrogen and helium d. Gravitational forces pull in gas and dust particles increasing the density of the nebula growing increasingly stronger. 2. Protostar a. First=Proto b. A massive concentration of gas and dust clump together to form a PROTOSTAR c. The force of gravity causes atoms to become so tightly packed in the core that pressure rises and light and heat are produced. Due to collision of dust and particles NOT NUCLEAR FUSION. d. No Nuclear fusion begins yet. 3. Nuclear Fusion(Star starts) a. The core of the protostar reaches 15 million degrees celsius b. Gravity forces particles together. c. The energy that was keeping the particles apart released a tremendous amount of energy. d. Hydrogen atoms fuse to form helium atoms and release energy that rushes outwards. e. Energy is radiated out at the photosphere causing the star to shine. 4. Becomes low-mass or high-mass star 5. Death: Low mass star becomes red giant then white dwarf 6. Death: High mass star becomes a Neutron star or black hole. Without detail process 1. Stellar nebula 2. Protostar 3. Nuclear fusion 4. Becomes low mass or high mass star 5. Death low mass star becomes red giant then white dwarf 6. Death high mass star becomes a neutron star or blackhole A small or large star would last longer? Larger stars have more fuel, but have to burn it faster to maintain equilibrium. Fusion occurs at a faster rate in larger stars, their fuel lasts a shorter length of time. A smaller star has less fuel but the rate of fusion is slower. Therefore, smaller stars live longer because the rate of fuel consumption is less rapid. Hertzsprung-Russell Diagram( Determines the brightness, color and how long a star will live.) Plots the absolute magnitude of the star against its temperature. Main sequence: Diagonal band that fits 90% of stars. Red Giants:large, bright, cool stars White dwarfs: Small, dim, hot Cooler stars have a larger surface area and are more brilliant Red colour=cool White colour=hot Death of a star: In about 5 billion years Our sun will KYS causing the core of the sun to shrink. The entire star will turn into a red giant. Outer layers of gas will start to blow away because the core doesn’t have enough gravity. This is called a planetary nebula. It will turn into a dense white star Death of stars bigger than our sun: After the main sequence stage, the massive star expands into a red supergiant. Once fusion stops, the star will collapse and the shock wave of all that energy meeting at tone point will cause the star to become a supernova. The star then becomes a blackhole or a neutron star. Neutron star A star with initial mass between 10 and 30 solar masses explode into a supernova, the core left behind is called a neutron star Extremely dense star made up of tightly packed neutrons. FYI: a spoonful of neutron stars is heavier than Mt. Everest An extremely dense quantity of matter in space from which not even light can escape. Occurs when a star of over 30 solar masses collapses. Gravitational force is so strong it pulls in any nearby matter. Lesson 6 The origin of the universe The Big Bang Theory The start of everything The Big Bang Theory is the idea of how the universe began. Widely accepted by scientists States the universe began as one very hot point. Big Bang evidence 1. Redshift of galaxies a. Tells us almost all of the galaxies we see are moving away from us so the universe is growing 2. Cosmic microwave background radiation a. Earliest light from the universe is 13.8 billion years old and has been stretched into microwaves 3. Gravitational waves 4. Ratio of Hydrogen to helium in the universe Doppler effect The apparent change in the frequency of a wave caused by relative motion between the source of the wave and the observer. Red shift The phenomena of light from galaxies shifting towards the red end of the visible spectrum, the object is moving away. Edwin Hubble saw that most galaxies were experiencing red shift; therefore moving away from each other. Blue Shift The phenomena of light from galaxies shifting towards the blue end of the visible spectrum, the object is moving towards us. Increasing wavelengths=less energy=less frequency Distant Galaxies have all of their visible light shifted into infrared Dark matter and dark energy Astronomers have observed that stars in a galaxy are moving faster than they should be considering the amount of visible matter out there Conclusion that there should be 10 times the amount of matter to hold the galaxies together Dark matter Composition Unknown subatomic particle Density About 5x the density of normal matter Gravity Attracts other objects Effect on universe Slows expansion of universe Amount in the universe About 27% of the universe is dark matter Distribution in universe Concentrated in galaxies and galaxy clusters Evidence Gravitational lensing, Galaxy rotation curves, and the cosmic microwave background. Dark energy Unknown form of energy Very low density Opposes force of gravity Accelerated expansion of universe About 68% of universe Uniform throughout space What happens to the sun’s radiation? How does it warm the Earth? Uv light, IR radiation 70% earth, 30% leave into space methane , greenhouse gases trap the infrared light in earth, 70% light warms the earth and the atmosphere traps the heat inside. Lesson 7 Space exploration Check slides not worth noting down

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