Science Yearly Revision PDF

Summary

This document covers yearly science revision topics. It includes sections on energy, cells, and the chemical world, with detailed descriptions of outcomes centered on electric circuits, cells, particle models of matter, and photosynthesis.

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Science Yearly Revision -Mingyui WU- Energy - only outcomes 12 and 13: Outcome 12: Construct and draw simple electric circuits Outcome 13: Identify that electric current and voltage involve electrical energy, which can be transformed i...

Science Yearly Revision -Mingyui WU- Energy - only outcomes 12 and 13: Outcome 12: Construct and draw simple electric circuits Outcome 13: Identify that electric current and voltage involve electrical energy, which can be transformed into other forms of energy in an electric circuit. Cells - all outcomes (see outcome sheet) Chemical World - all outcomes (see outcome sheet) Rock Your World - all outcomes (see outcome sheet) ENERGY - TOPIC ONE OUTCOME 12 & 13: COMPONENTS SYMBOL DEFINITION Power Supply (Battery) Provides energy to the circuit Light Bulb/Globe Emit light (provide light energy) Wire Transfer energy between circuit components Voltmeter Measures the voltage across a To measure voltage, the circuit component voltmeter and circuit component must be parallel to each other To measure current, the ammeter must be in series with the circuit component Ammeter Measures the current in a circuit Resistor Provides resistance to the circuit which controls the flow Voltage- the energy provided to a circuit, measured in volts (V) Current- quantity of charge flowing through the circuit per second, measured in Amperes (A) CELLS- TOPIC TWO OUTCOME 1:MRS GREN M:Movement - create motion to perform a function R:Respiration-mechanism to provide energy to cells S:Sensitivity - ability to respond to external (environmental) stimuli G:Growth: change in mass and repair itself R:Reproduction:create offspring (i.e. child) E:Excrete:get rid of wastes Nutrition:food for health and growth OUTCOME 2: SKILL - IDENTIFY THE PARTS OF A LIGHT MICROSCOPE AND THEIR FUNCTIONS. PARTS OF THE MICROSCOPE FUNCTION Eyepiece Observe the specimen or object Objective Lens Various lenses with differing magnification to enlarge the image of the specimen or magnify a certain part of the specimen Arm Support the whole microscope for stability Stage Surface that holds the specimen Stage Clip Holds the specimen in place for stability Coarse Focus Knob Roughly adjust the stage so that the specimen is in focus Fine Focus Knob Subtly adjust the stage so that the specimen is in focus Diaphragm Control of the light passing through the specimen Light Source Emit light OUTCOME 3:DISTINGUISH BETWEEN UNICELLULAR AND MULTICELLULAR ORGANISMS. UNICELLULAR MULTICELLULAR One cell Multiple cells Must conduct all living process Specialised cells that conduct certain Has a cell wall for protection living processes Circular DNA6 No cell wall - protection to the immune Flagellum for movement system Linear DNA Musculoskeletal + nervous system OUTCOME 4:CONSTRUCT A TABLE TO DESCRIBE THE FUNCTION OF THE CELL ORGANELLES (INCLUDING NUCLEUS, CYTOPLASM, CELL MEMBRANE, CELL WALL, CHLOROPLAST, MITOCHONDRIA, VACUOLE). Animal and plant cells share several common structures, but they also possess key differences that define their roles in living organisms. Both types of cells are eukaryotic, meaning they have a true nucleus enclosed by a membrane, and they contain organelles like mitochondria, the Golgi apparatus, and the endoplasmic reticulum, which are vital for various cellular functions such as energy production, protein synthesis, and molecule transport. One key similarity is the presence of the nucleus in both animal and plant cells, which houses genetic material (DNA) and coordinates cellular activities, including growth, metabolism, and reproduction. Both cells also have mitochondria, often referred to as the powerhouse of the cell, where ATP (energy) is produced through cellular respiration. However, plant cells have additional structures that animal cells lack. For instance, plant cells contain a cell wall made of cellulose, which provides structural support and protection. This rigid structure helps plants maintain their shape and withstand changes in water pressure. In contrast, animal cells only have a flexible plasma membrane, which provides more mobility but less structural rigidity. Another major difference is the presence of chloroplasts in plant cells. Chloroplasts contain chlorophyll, a pigment that captures sunlight for photosynthesis, the process by which plants convert light energy into chemical energy (glucose). This allows plants to produce their own food, whereas animal cells rely on external sources for nutrients. Additionally, plant cells have a large central vacuole that stores water, nutrients, and waste products. The vacuole helps maintain cell turgor pressure, which keeps the plant firm and upright. In contrast, animal cells contain smaller, more numerous vacuoles, which perform similar storage functions but do not play a role in maintaining rigidity. Large Central Vacuole - Water balance - Storage - Restricted movement - Structural support OUTCOME 7: IDENTIFY SITUATION IN WHICH MITOSIS OCCURS ; OUTCOME 8: STATE THAT CELLS USE CELLULAR RESPIRATION TO CONVERT CHEMICAL ENERGY TRAPPED IN GLUCOSE INTO ENERGY FOR CELLS; OUTCOME 9: DESCRIBE CELLULAR RESPIRATION AND IDENTIFY MITOCHONDRIA AS THE ORGANELLE IN WHICH CELLULAR RESPIRATION OCCURS Mitosis is a process of cell duplication, or reproduction, during which one cell gives rise to two genetically identical daughter cells. OUTCOME 10: USE THE WORD EQUATION BELOW TO DESCRIBE WHAT HAPPENS DURING CELLULAR RESPIRATION: GLUCOSE + OXYGEN ⇾ WATER + CARBON DIOXIDE Cellular respiration is chemical energy converted into energy for cells, where mitochondria is found, in which all cells need cellular respiration. The word equation equals glucose + oxygen -> carbon dioxide + water. OUTCOME 11: DESCRIBE THE ROLE OF THE FLOWER, ROOT, STEM AND LEAF IN FLOWERING PLANTS. FLOWER:A flower, also known as a bloom or blossom, is the reproductive structure found in flowering plants. ROOT: A root the part of a plant which attaches it to the ground or to a support, typically underground, conveying water and nourishment to the rest of the plant via numerous branches and fibres. STEM:A stem is one of two main structural axes of a vascular plant, the other being the root. It supports leaves, flowers and fruits, transports water and dissolved substances between the roots and the shoots in the xylem and phloem, engages in photosynthesis, stores nutrients, and produces new living tissue LEAF:Leaf is a flattened structure of a higher plant, typically green and blade-like, that is attached to a stem directly or via a stalk. Leaves are the main organs of photosynthesis and transpiration. OUTCOME 12:OUTLINE HOW PLANTS USE SUNLIGHT TO PRODUCE GLUCOSE DURING PHOTOSYNTHESIS Light Absorption: Chloroplasts contain a green pigment called chlorophyll, which absorbs light, mostly in the blue and red wavelengths. This light energy is captured by the thylakoid membranes inside the chloroplasts. Light-Dependent Reactions: The absorbed light energy excites electrons in chlorophyll, starting the light-dependent reactions. These reactions take place in the thylakoid membranes and convert light energy into chemical energy in the form of ATP (adenosine triphosphate) and NADPH (nicotinamide adenine dinucleotide phosphate). Water molecules (H₂O) are split in this process, releasing oxygen (O₂) as a byproduct.Two molecules of G3P are then used to form one molecule of glucose (C₆H₁₂O₆), a sugar that provides energy for the plant and other organisms. OUTCOME 13: USE THE WORD EQUATION TO DESCRIBE WHAT OCCURS DURING PHOTOSYNTHESIS: light energy & chlorophyll water + carbon dioxide -----→ glucose + oxygen OUTCOME 14: IDENTIFY THE CHLOROPLAST AS THE ORGANELLE IN WHICH PHOTOSYNTHESIS OCCURS (IT CONTAINS CHLOROPHYLL) AND CHLOROPHYLL AS THE GREEN PIGMENT IN PLANTS THAT ABSORBS ENERGY FROM THE SUNLIGHT DURING PHOTOSYNTHESIS The chloroplast is the organelle in plant cells where photosynthesis takes place. It plays a crucial role in capturing light energy and converting it into chemical energy in the form of glucose. Inside the chloroplast, there is a green pigment called chlorophyll. Chlorophyll is responsible for absorbing energy from sunlight, particularly in the blue and red parts of the light spectrum. This energy is used to drive the initial steps of photosynthesis, where light energy is converted into chemical energy. Chlorophyll is housed within structures called thylakoid membranes, which are stacked within the chloroplasts. By absorbing sunlight, chlorophyll enables the plant to initiate the process of converting carbon dioxide and water into glucose, releasing oxygen as a byproduct. Chlorophyll’s green colour is due to the fact that it reflects green light, which is why plants appear green to us. CHEMICAL WORLD- TOPIC THREE OUTCOME ONE USE THE PARTICLE MODEL OF MATTER TO: - DESCRIBE ARRANGEMENT, MOVEMENT AND ENERGY OF PARTICLES IN SOLIDS, LIQUIDS AND GASES - DESCRIBE THE PROPERTIES OF SOLIDS, LIQUIDS AND GASES Solids - Solids are states of matter that have a definite volume and shape. - The particles in a solid are tightly packed together and have a strong attraction to each other, which keeps its rigid composition making it difficult for them to move freely. - Solids cannot be compressed. Liquids - Liquids are a state of matter that have a definite volume, but take the shape of the container. - These particles in a liquid are loosely packed together and have a weaker attraction to each other than other particles, allowing them to move freely. - Liquids cannot be compressed. Gases - Gases are a state of matter which do not have a definite shape or volume and will fill any container with which they are composed. - The particles of gases are widely spaced apart and have a very weak attraction to each other, which allows them to move freely and randomly. - Gases can be compressed. OUTCOME 2: IDENTIFY THE PROCESSES INVOLVED IN CHANGES OF STATE AS: - BOILING, MELTING, FREEZING, CONDENSATION, EVAPORATION AND SUBLIMATION - PREDICT THE EFFECT OF ADDING / REMOVING HEAT Diffusion is the process by which particles spread out from an area of higher concentration to an area of low concentration, this will depend on the movement of the particles in a substance. Diffusion in solids rarely happens, in liquids they happen more than solids but less than gases. Diffusion in gases.are faster than both liquids and solids. → Freezing - turning to ice, which the temperature becomes below 0 degrees celsius. →Condensing - to make more dense or compact, the conversion of a substance →Melting - the process in which solid substance are converted into liquids by heat →Boiling - is the process in which a liquid turns into vapour when it's heated to its boiling point. This occurs when the vapour pressure of the liquid is equal to the atmospheric pressure. →Evaporating - vaporisation that occurs on the surface of a liquid that starts to lose moisture or solvent as vapour into its gas phase →Sublimation - conversion of a substance from the solid to the gaseous state without its becoming liquid. An example is the vaporisation of frozen carbon dioxide (dry ice) at ordinary atmospheric pressure and temperature. 𝑀 OUTCOME 3 :USE A SIMPLE PARTICLE MODEL TO DESCRIBE DENSITY AND CALCULATE DENSITY USING D = 𝑉 -Density defines how compact a substance is. The closer the particles are together (more compact) the more dense it is. OUTCOME 4: ASSESS THE BENEFITS AND LIMITATIONS OF USING MODELS, AND DESCRIBE WHY MODELS CHANGE OVER TIME. Based on all his observations, Dalton proposed his model of an atom. It is often referred to as the billiard ball model. He defined an atom to be a ball-like structure, as the concepts of atomic nucleus and electrons were unknown at the time. His statements were based on the three laws. He stated the following postulates (not all of them are true) about his atomic theory. Matter is made of very tiny particles called atoms. Atoms are indivisible structures, which can neither be created nor destroyed during a chemical reaction (based on the law of conservation of mass). All atoms of a particular element are similar in all respects, be it their physical or chemical properties. Inversely, atoms of different elements show different properties, and they have different masses and different chemical properties. Atoms combine in the ratio of small whole numbers to form stable compounds, which is how they exist in nature. The relative number and the kinds of atoms in a given compound are always in a fixed ratio (based on the law of constant proportions) Drawbacks: The first part of the second postulate was not accepted. Bohr's model proposed that the atoms could be further divided into protons, neutrons, and electrons. The third postulate was also proven to be wrong because of the existence of isotopes, which are atoms of the same element but of different masses. The fourth postulate was also proven to be wrong because of the existence of isobars, which are atoms of different elements but of the same mass. JJ THOMPSON - 1897 J.J. Thomson's experiments with cathode ray tubes showed that all atoms contain tiny negatively charged subatomic particles or electrons. Thomson's plum pudding model of the atom had negatively-charged electrons embedded within a positively-charged "soup. ERNEST RUTHERFORD 1908 - 1913 From the evidence Rutherford proposed: Atoms have a small, dense positively charged nucleus 1. 2.Atoms are mostly empty space Electrons must be outside the nucleus Rutherford also thought that each positive charge in the nucleus would have a mass of 1. The model described the atom as a tiny, dense, positively charged core called a nucleus, in which nearly all the mass is concentrated, around which the light, negative constituents, called electrons, circulate at some distance, much like planets revolving around the Sun. JAMES CHADWICK James Chadwick discovered that atoms consisted not only of protons and electrons but also neutrons. Chadwick discovered the neutron, a neutral subatomic particle that has approximately the same mass as a proton. James Chadwick discovered a particle with the same mass as a Hydrogen nucleus but neutral charge. NEIL BOHR - 1913 In 1913, Bohr proposed a model of the atom where electrons orbit the nucleus in fixed paths or energy levels, similar to planets orbiting the sun. His model explained how light is emitted absorbed by electrons as they move up/down energy levels. Key points included: Electrons occupy specific energy levels. Electrons can jump between energy levels, emitting or absorbing a proton (light). OUTCOME 5:IDENTIFY THAT ELEMENTS ARE MADE OF ATOMS, EACH WITH A UNIQUE ARRANGEMENT OF PROTONS, NEUTRONS AND ELECTRONS. Protons - Located in the nucleus of the atom. They have a positive charge and a relative mass of 1. ⇒The proton is a subatomic particle with a positive electrical charge. They are found in every atomic nucleus of every element. In almost every element, protons are accompanied by neutrons. The only exception is the nucleus of the simplest element, hydrogen. Hydrogen contains only a single proton and no neutrons. Neutrons - Located in the nucleus, have a charge of 0 and a relative mass of 1.008. ⇒Neutrons, along with protons, are subatomic particles found inside the nucleus of every atom. The only exception is hydrogen, where the nucleus contains only a single proton. Neutrons have a neutral electric charge (neither negative nor positive) and have slightly more mass than positively charged protons. Electrons - Located in shells orbiting the nucleus. They have a negative charge and a relative mass of 0.005. ⇒An electron is a negatively charged subatomic particle that can be either bound to an atom or free (not bound). An electron that is bound to an atom is one of the three primary types of particles within the atom -- the other two are protons and neutrons. Together, protons and electrons form an atom's nucleus. OUTCOME 6: USE THE PERIODIC TABLE TO IDENTIFY AND USE SYMBOLS FOR ELEMENTS. OUTCOME 7: DISTINGUISH BETWEEN METALS AND NONMETALS IN TERMS OF THEIR PROPERTIES. (APPEARANCE, MALLEABILITY, MELTING POINT, ELECTRICAL CONDUCTIVITY AND HEAT CONDUCTIVITY) Appearance: Metals: Shiny, lustrous surfaces that reflect light. Examples include gold, silver, and aluminium. Non-metals: Often dull and non-reflective. For instance, sulphur and carbon (graphite) have a matte appearance. Malleability (ability to be hammered or bent without breaking): Metals: Highly malleable; they can be hammered into sheets (like aluminium foil) without breaking. Non-metals: Brittle; they tend to shatter or break when hammered (e.g., sulphur and phosphorus). Melting Point: Metals: Generally have high melting points. For example, iron melts at around 1,538°C. Non-metals: Lower melting points compared to metals. Sulphur, for example, melts at 115°C. Electrical Conductivity: Metals: Excellent conductors of electricity. Copper is widely used in electrical wiring because of this. Non-metals: Poor conductors of electricity, with exceptions like graphite, which can conduct electricity. Heat Conductivity: Metals: Good conductors of heat, which is why metals like copper and aluminium are used in cookware. Non-metals: Poor conductors of heat. Materials like wood or rubber (which are non-metallic) are used as insulators. OUTCOME 8: NAME SOME ELEMENTS AND THEIR PROPERTIES BY REFERRING TO THEIR POSITION ON THE PERIODIC TABLE. OUTCOME 9: For common substances e.g. O2 , H2O, CO2 , CH4 , C6H12O6 , NaCl and MgO - identify the type and number of atoms in the substances - write the chemical formula OUTCOME 10: DRAW PARTICLE DIAGRAMS TO COMPARE ELEMENTS, COMPOUNDS AND MIXTURES. ELEMENTS:An element is a substance made up of only one type of atom, each with the same number of protons. Each element cannot be broken down into simpler substances. Each element retains its basic physical properties, regardless of the number of atoms in a sample. COMPOUNDS:A compound is two or more different elements that are chemically bonded together. MIXTURE: A mixture is a substance that contains two or more types of atom that are not chemically joined together (not bonded). MOLECULES: Molecules are made up of one or more atoms. If they contain more than one atom, the atoms can be the same (an oxygen molecule has two oxygen atoms) or different (a water molecule has two hydrogen atoms and one oxygen atom). Biological molecules, such as proteins and DNA, can be made up of many thousands of atoms. EXAMPLE: Olympic Medals: Gold- Element, Silver- Element, Bronze: Tin, Copper & Zinc - Mixture OUTCOME 11: LIST SIGNS OF A CHEMICAL REACTION AND RECOGNISE THAT NEW SUBSTANCES ARE FORMED Colour Change: A change in colour indicates that new substances with different properties are forming. This change is often due to the formation of compounds that reflect light differently than the original reactants. Temperature Change: When a chemical reaction occurs, heat may be absorbed (endothermic) or released (exothermic). This change in temperature signals the breaking and forming of chemical bonds in new substances. Gas Production: The appearance of bubbles, fizzing, or smoke indicates that a gas is being produced. This gas is a new substance formed from the reactants during the reaction. Precipitate Formation: A precipitate is a solid that forms when two liquids react and produce an insoluble compound. Its appearance shows that new substances have been created in the reaction. Change in Odour: A different smell suggests that new chemicals are being formed with distinct properties. This is common in reactions involving organic compounds, where new molecules with different odours are produced. Light or Sound Emission: Some reactions release energy in the form of light (like fireworks) or sound (like an explosion). This release is evidence of new substances forming and releasing stored chemical energy. OUTCOMES 12: USE WORD EQUATIONS TO REPRESENT REACTIONS, WITH REACTANTS AND PRODUCTS CHEMICAL REACTIONS: CHEMICAL CHANGES: ​Chemical changes happen when chemical reactions occur. They involve the formation of new chemical elements or compounds. PHYSICAL CHANGES: Physical changes do not lead to new chemical substances forming. In a physical change, a substance simply changes physical state, eg from a solid to a liquid - Change of Shape: For example if a force is applied to break, bend, stretch, crush, twist or compress the object, there is a change in shape or form.. These changes do not produce new substances. For example, when you crush an aluminium can, its shape changes but it is still made of the same aluminium as before - Expansion and Contraction: Physical changes also occur when the temperature of a substance increases or decreases. When expansion occurs, the volume of the object increases and its density decreases but no new substances are formed. When a solid, liquid or gas is cooled, it contracts (takes up less space). When contraction occurs, the volume of an object decreases and its density increases. CHEMICAL AND PHYSICAL CHANGES: Physical Changes Chemical Changes - Breaking glass - Digesting food - Water evaporating from a river - Photosynthesis - Cutting paper - Baking chicken - Condensation on the window - Toasting Bread - Glowing light bulb - Burning Candle - Dissolving salt - Milk turning sour - Boiling water - Burning wood - Melting chocolate - Using a Battery OUTCOME 13: DISTINGUISH BETWEEN PHYSICAL AND CHEMICAL CHANGES IN TERMS OF THE ARRANGEMENT OF PARTICLES AND REVERSIBILITY OF THE PROCESS. E.G. BOILING WATER AND DECOMPOSITION OF WATER REVERSIBLE AND IRREVERSIBLE CHANGES: Reversible: A substance can return to its original state. The chemical properties of the substance do not change. Most physical changes are reversible changes. Irreversible : A substance cannot return to its original state. The chemical properties of the substance change. Most physical changes are irreversible changes. PHYSICAL CHANGES: MIXING: - Mixing two substances represents another type of physical change The colours are evenly distributed throughout the mixture, no reaction takes place, they are not chemically bonded and no colour change occurs DISSOLVING: - When a solid (solute) is dissolved in a liquid (solvent), they form a solution. A solution is a mixture. The smallest particles of the solute mix and spread evenly throughout the smallest particles of the solvent—just like a mixture of balls but invisible to the naked eye. OUTCOME 14: DISCUSS THE IMPORTANCE OF CHEMICAL REACTIONS FOR LIFE. E.G. PHOTOSYNTHESIS, RESPIRATION, FERMENTATION, COOKING. CHEMICAL REACTIONS IN NATURE Chemical reactions are processes in which reactants undergo transformation into new products, typically characterised by distinct chemical properties. These reactions occur ubiquitously in natural systems and are fundamental to many observable phenomena and everyday experiences. Combustion Photosynthesis Cooking Respiration Acid Rain Fermentation PHOTOSYNTHESIS: The process plants use to synthesise (make) glucose. THIS happens in chloroplasts (mainly in the leaves). It's an endothermic process – it requires light energy (taken In from the surroundings). RESPIRATION: All organisms need a constant energy supply. Mammals and birds need energy to maintain a constant body temperature. Energy is also needed for the following life processes such as: growth muscle contraction protein synthesis AEROBIC RESPIRATION: - Release of energy in cells. Chemical reaction breaking down glucose using oxygen. - GLUCOSE + OXYGEN —----> CARBON DIOXIDE + WATER - OCCURS IN MITOCHONDRIA - RELEASES LOTS OF ENERGY RAGB RESPIRATION:. GLUCOSE + OXYGEN —----> CARBON DIOXIDE + WATER C6H12O6 + 02 —--> C02 + H20 GLUCOSE —--> LACTIC ACID C6H12O6 —---> 2C3H6O3 RESPIRATION VS BREATHING: Plants respire anaerobically like yeast.Another name for this is fermentation. Chemical Equation: Glucose —-> Ethanol + Carbon Dioxide ROCK YOUR WORLD- TOPIC FOUR LO1: DESCRIBE THE STRUCTURE OF THE EARTH IN TERMS OF INNER CORE,OUTER CORE, MANTLE AND CRUST (E.G. TEMPERATURE, THICKNESS, PHYSICAL STATE, COMPOSITION OF CORE) 17/9/2024 THE HISTORY OF THE EARTH About 4.5 billion years ago, the Earth formed from a cloud of gas and dust left over from the formation of the Sun. Gravity pulled this material together, creating a hot, molten planet. Over time, the Earth cooled, and the outer layer solidified to form a crust. Volcanic activity released gases, creating the early atmosphere. MODELLING THE STRUCTURE OF THE EARTH 18/9/2024 OUTER CORE: The Earth's outer core is a liquid layer mainly composed of iron and nickel, located between the mantle and the inner core, at depths of about 2,890 to 5,150 kilometres. With temperatures ranging from 4,000°C to 6,000°C, the intense heat keeps the outer core in a molten state. The movement of liquid metals within it generates the Earth's magnetic field, which protects the planet from harmful solar radiation. INNER CORE: The Earth's inner core is a solid sphere primarily made of iron and nickel, located at the planet's centre, about 5,150 to 6,371 kilometres beneath the surface. Despite extreme temperatures reaching up to 5,700°C,the inner core remains solid due to the immense pressure exerted on it. It is responsible for helping maintain Earth's magnetic field by interacting with the liquid outer core. The inner core is slowly growing as the outer core cools and solidifies over time. MANTLE: The Earth's mantle is a thick, semi-solid layer located between the crust and the outer core, extending from about 30 to 2,900 kilometres below the surface. Composed mainly of silicate rocks rich in magnesium and iron, it makes up about 84% of Earth's total volume. The mantle is divided into the upper and lower mantle, with slow-moving convection currents that drive plate tectonics, causing the movement of Earth's crust. CRUST: The Earth's crust is its outermost layer, varying in thickness from about 5 kilometres under oceans (oceanic crust) to around 30-70 kilometres under continents (continental crust). It consists primarily of rocks, minerals, and various elements like silicon, aluminium, and oxygen. The crust is divided into tectonic plates that float on the semi-fluid mantle, causing geological activity like earthquakes and volcanic eruptions. This thin, solid layer supports all life forms, housing ecosystems, landforms, and oceans. LO2 DISTINGUISH BETWEEN ROCKS AND MINERALS 19/92024 A mineral is a naturally occurring, solid substance with a specific chemical composition and crystal structure. A rock, on the other hand, is made up of one or more minerals. Rocks can be classified into three types: igneous, sedimentary and metamorphic. Minerals are naturally occurring elements or compounds found in the earth. There are over 4000 minerals formed from only 12 of the elements on our periodic table. They are the building blocks of our planet and they are mostly inorganic solids. This means that they are not derived from living matter and contain no carbon compounds. They are defined based on their chemical composition (which elements form them) and their crystal structure (how they are joined together). Examples of minerals include: sodium (found in salt), potassium (found in bananas), gold, quartz, gypsum (mined in Australia), aluminium and sulphur. Opal is a hydrated silica mineral known for its stunning "play of colour" due to light diffraction within its structure. It ranges from opaque to translucent and ranks 5.5 to 6.5 on the Mohs hardness scale. Found mainly in Australia, opal mining can cause environmental damage, such as land disruption and water overuse, and can also raise land rights concerns with indigenous communities. Tourmaline, on the other hand, is a complex boron silicate mineral with a wide colour range, from pink to green and even multi-colored varieties. It is relatively durable, scoring 7 to 7.5 on the Mohs scale, and is primarily mined in Brazil, Afghanistan, and parts of Africa. Tourmaline mining can also be controversial, as it may lead to habitat destruction, water pollution, and labour exploitation, particularly in regions with weak mining regulations. LO4 EXPLORE THE POSITIVE AND NEGATIVE IMPACTS OF MINING, INCLUDING ECONOMIC AND ENVIRONMENTAL FACTORS ORES: Ores are naturally occurring rocks or minerals that contain valuable metals or other elements that can be extracted and used. Some common ores include: Bauxite: used to make aluminium. Hematite: used to extract iron. Chalcopyrite: used to get copper. STEPS INVOLVED IN MINING: Exploration: Geologists identify areas with potential mineral deposits. They use surveys, drilling, and sampling to assess the location and concentration of the minerals. Extraction: Surface Mining - Includes open-pit, this is used for shallow mineral deposits. Underground Mining - Involves digging tunnels or shafts to reach deep-seated minerals. Placer Mining - Extracts valuable minerals from riverbeds or beach sands. Ore Processing: Once mined, the ore is crushed and ground to free the valuable minerals. Depending on the mineral, additional processes like magnetic separation are used to refine it. Waste Management: Unwanted materials, called tailings, are managed and stored to minimise environmental impact. Reclamation: After mining, the site is rehabilitated. This involves refilling pits, replanting vegetation, and ensuring the ecosystem recovers. LO3 CLASSIFY VARIETY OF COMMON MINERALS INTO GROUPS BASED ON THEIR CHARACTERISTICS (E.G. COLOUR, LUSTRE, STREAK,HARDNESS) RECAP Minerals are non living materials found in nature. There are more than 2,000 different minerals on earth. Quartz, talc, halite (rock salt), magnetite, feldspar, and mica are a few common minerals. Minerals are pure substances and often contain only one compound. They form crystal structures. All rocks are made from minerals. Rocks are often mixtures of various minerals. They are not pure substances and have wide ranging properties. CLASSIFICATION OF MINERALS - categorising minerals THE MOHS SCALE The Mohs scale is a way to measure the hardness of minerals by seeing how easily they can be scratched. It ranks minerals from 1 to 10, with 1 being the softest and 10 being the hardest. A mineral can scratch any mineral that is softer than itself but can be scratched by any mineral that is harder. Here's how it works: Talc is the softest mineral, with a hardness of 1. It can be easily scratched by everything. Diamond is the hardest mineral, with a hardness of 10, and it can scratch all other minerals. For example, if a mineral has a hardness of 6, it can scratch minerals with a hardness of 5 or lower, but it can be scratched by minerals with a hardness of 7 or higher OTHER CHARACTERISTICS USED TO CLASSIFY MINERALS Colour - Scientists will observe the colour of minerals in detail and document. Lustre - Describes how light reflects off the surface of a mineral. It can be described as metallic (shiny like metal) or non-metallic (glassy, pearly, dull, etc.) Crystal shape and size - Crystal shape refers to the geometric shape a mineral forms as it naturally grows. Common shapes include cubes, prisms, and hexagons. Size refers to how large or small the individual crystals are. Streak - Streak is the colour of the powdered form of a mineral, which can be observed by rubbing the mineral on an unglazed porcelain plate LO4 EXPLORE THE POSITIVE AND NEGATIVE IMPACTS OF MINING, INCLUDING ECONOMIC AND ENVIRONMENTAL FACTORS POSITIVES AND NEGATIVES OF MINING: POSITIVE NEGATIVE Economic Growth: Mining contributes to Environmental Degradation: GDP and job creation, especially in Deforestation, soil erosion, and loss of developing regions. biodiversity. Resource Supply: Provides essential Water Pollution: Chemicals used in minerals for technology, construction, and mining can contaminate water sources. industry. Air Pollution: Dust, emissions, and release Infrastructure Development: Roads, of harmful gases like sulphur dioxide. power lines, and facilities are often Health Hazards: Miners face risks of lung developed alongside mining activities. diseases, accidents, and exposure to Foreign Investment: Attracts investment harmful substances. to countries with abundant resources. Displacement: Local communities may be Job Opportunities: Mining provides forced to relocate, losing homes and employment in areas with limited livelihoods. economic activities. Exhaustion of Resources: Non-renewable Revenue for Governments: Through taxes resources are depleted, leaving behind and royalties, mining boosts public abandoned mines. finances. Energy Intensive: Mining consumes large Contribution to Global Trade: Minerals amounts of energy, contributing to are important commodities in greenhouse gas emissions international markets. Social Conflict: Mining projects can lead to conflicts between companies and local communities over land and resources. Waste Generation: Mining generates large amounts of waste, including tailings and slag. CIRCLE OF VIEWPOINTS 1. Local People’s Viewpoint: Positive Aspects: Ruby mining brings job opportunities to the region, providing a source of income for many who would otherwise struggle to make a living. Additionally, mining attracts infrastructure development, such as roads, clinics, and schools, as mining companies invest in the local area. Negative Aspects: Despite the economic benefits, locals often feel that they receive a disproportionately small share of the wealth generated by the mining operations. There are concerns about environmental degradation, deforestation, and water contamination, which harm agriculture and local livelihoods. Some fear that ruby mining disrupts traditional ways of life, and there are reports of displacement due to mining expansion. 2. Miners’ Viewpoint: Positive Aspects: Ruby mining provides financial opportunities that many miners wouldn't have access to otherwise. Many miners see this as a way to lift themselves and their families out of poverty. Working as a miner, even informally, offers quick cash, especially when high-quality rubies are found. Negative Aspects: Working conditions can be extremely dangerous, particularly for artisanal miners who often work without proper safety equipment or legal protections. Conflict between informal miners and mining companies can result in confrontations, and many miners feel exploited, receiving very little compensation for their hard labor. Miners also face health risks due to poor working conditions and a lack of regulation. 3. Police Viewpoint: Positive Aspects: From the police perspective, maintaining order around mining sites is critical. They are tasked with enforcing laws, including preventing illegal mining, which is seen as necessary to protect Mozambique’s valuable resources and ensure that mining remains a controlled and profitable industry. Policing these areas also helps to maintain national security by limiting the influence of criminal networks. Negative Aspects: However, there are allegations of corruption and brutality within the police force, with accusations that some officers accept bribes from illegal miners or use excessive force to control crowds of informal miners. Police forces are often stretched thin and may struggle to balance enforcing the law with protecting vulnerable populations. The presence of police may create tension in local communities, as they are often seen as siding with foreign-owned mining companies rather than protecting the rights of the people. LO5 CLASSIFY A VARIETY OF COMMON ROCKS AS IGNEOUS, SEDIMENTARY OR METAMORPHIC USING THEIR CHARACTERISTICS. LO6 DESCRIBE THE FORMATION OF IGNEOUS ROCKS FROM COOLED MAGMA CLASSIFYING ROCKS: Scientists class all rocks from the Earth’ s crust into three categories that we look at over the next three lessons. They are: Sedimentary rocks- e.g. limestone; Igneous rocks- e.g. granite and Metamorphic rocks- e.g. marble These three types of rock are made in different ways and under different conditions. FORMATION OF IGNEOUS ROCKS: IGNEOUS ROCKS: Igneous rocks come from volcanoes. Deep in the ground is molten rock called magma. Sometimes, magma bursts through the surface causing volcanic eruptions. Igneous rocks are formed when magma cools and solidifies. When magma cools above the surface, extrusive igneous rocks are formed. When magma cools below the surface, intrusive igneous rocks are formed. LO5 CLASSIFY A VARIETY OF COMMON ROCKS AS IGNEOUS, SEDIMENTARY OR METAMORPHIC USING THEIR CHARACTERISTICS. LO7 EXPLAIN HOW ROCKS CAN BE BROKEN DOWN THROUGH WEATHERING. LO8 DISTINGUISH BETWEEN WEATHERING AND EROSION WEATHERING VERSUS EROSION WEATHERING Weathering is the process that breaks down rocks into smaller pieces right where they are, without moving them. It can happen through physical means (like freezing and thawing that cracks rocks) or chemical means (like acid rain that dissolves minerals in rocks). Example: Water gets into cracks in a rock, freezes, and makes the cracks bigger, eventually breaking the rock apart. EROSION Erosion is the process of moving the broken-down pieces (sediment) away from their original location, usually by wind, water, or ice. Example: After weathering breaks rocks into pieces, a river can carry the sediment downstream, moving it to a new place. In short: weathering breaks down rocks, while erosion moves the pieces away. WEATHERING INVESTIGATION: Physical weathering is when rocks break down into smaller pieces through physical forces without changing their chemical makeup. This is sometimes called mechanical weathering. This can happen due to temperature changes, water, ice, or wind. For example, when water gets into cracks in rocks and freezes, it expands, causing the rock to crack further (this is called frost wedging). Physical weathering can also happen through pressure from growing plant roots or abrasion from wind and water. Chemical weathering involves the chemical breakdown of rocks. It happens when the minerals in rocks react with water, air, or other chemicals, causing the rock to change its composition and weaken. This can happen through processes like oxidation (when minerals react with oxygen and rust), reactions with water, or reactions with acids, like carbonic acid from carbon dioxide dissolving in rainwater. LO9 DESCRIBE AND INTERPRET SEDIMENTARY ROCK LAYERS LO10: DESCRIBE HOW FOSSILS FORM IN SEDIMENTARY ROCKS LO11: DESCRIBE THE EFFECT OF HEAT AND PRESSURE THE FORMATION OF METAMORPHIC ROCKS RED: WHAT ARE SEDIMENTS? - Sediments are matter that settles to the bottom of a liquid. Metamorphic rocks are formed from SEDIMENTARY and IGNEOUS rocks that have become changed by HEAT and PRESSURE from within the EARTH.

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