Classifying Matter - PDF
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This document explains the basics of matter classification, including pure substances, elements, compounds, mixtures, heterogeneous mixtures, and homogeneous mixtures. It also details the particle theory and how atoms, molecules and the arrangements of particles influence the properties of matter. The document includes questions about matter and mixtures.
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CLASSIFYING MATTER Matter Hierarchy and Types of Particles WHAT IS HIERARCHY Hierarchy: a system in which groups are ranked above one another according in levels Biology Example Workplace Example Trophic level hierarchy – who eats what Job hierarchy...
CLASSIFYING MATTER Matter Hierarchy and Types of Particles WHAT IS HIERARCHY Hierarchy: a system in which groups are ranked above one another according in levels Biology Example Workplace Example Trophic level hierarchy – who eats what Job hierarchy (who bosses around who)? MATTER HIERARCHY -In Chemistry, we classify matter into a matter hierarchy to things are easier to understand Matter Anything that has mass & takes up space Pure Substances Mixtures All particles in the Contain 2 or more pure substances substance are the same Elements Compounds Solutions Heterogeneous Contain 2 or more Cannot be broken different elements Have 1 visible Mixtures Down into simpler Component Contain 2 or in fixed Substances Ex. koolaid More parts proportions Ex. Fe, Mg, Cl2 Ex. Salad dressing Ex. H2O, CO2 PURE SUBSTANCES How are they both pure substances when they are both so different? PURE SUBSTANCES Element Compound cannot be broken down into a simpler Composed of two or more elements chemical substance by any physical or bonded chemically in fixed proportions chemical means E.g. Table salt- is sodium and chlorine found on periodic table elements combined chemically TYPES OF PARTICLES Atoms Molecules -the type of particle of most elements -particles that are chemically bonded -Each element is made up of a unique together atom -basic building block for compounds Just like lego pieces are all unique with unique name, atoms are all unique with unique element name MOLECULAR ELEMENTS ELEMENT OR COMPOUND? ATOM OR MOLECULE? ELEMENT OR COMPOUND? ATOM OR MOLECULE? Element/atom Compound/molecule Element/molecule Compound/molecule Compound/molecule Element/atom E.g. copper E.g. CH4 (methane) E.g. chlorine (Cl2) carbon monoxide (CO) ammonia (NH3) E.g. argon MIXTURES -combination of two or more pure substances -mixture of particles rather than one Heterogeneous (or Mechanical) Homogeneous (or Solution) -can see multiple phases (can tell it’s a -can see only one phase (can’t tell it’s a mixture) mixture) WHAT TYPE OF MIXTURE? Heterogeneous Homogeneous Homogeneous -Air is made up -apple juice is of nitrogen gas, made up of oxygen gas, sugar, water, and carbon dioxide, other compounds and water vapour QUIZ 1. Salt and helium are pure substances. This 2. Oxygen is a(n) is because they A) Hetergeneous mixture A) are each made up of only one type of particle B) Compound B) are both elements C) Homogeneous mixture C) have the same physical properties D) Element D) are both compounds QUIZ 3. Sugar is made of carbon, hydrogen, and 4. Brass, a metal alloy used to make many oxygen chemically bound together. It is a(n) instruments, is made up of both copper and zinc. It is a(n) A) homogeneous mixture A) heterogeneous mixture B) element B) compound C) compound C) homogeneous mixture D) heterogeneous mixture D) element Chemistry Introduction Matter, the Particle Theory, and States of Matter What is Chemistry? the study of matter and its properties and interactions matter: anything that takes of space and has mass Volume: measure of space (e.g. mL, L, cm3) Mass: measured using balance (e.g. kg, g, lb) The Particle Theory The Particle Theory explains how all matter (liquid, solid, gas) is structured and how it behaves under certain conditions. The Particle Theory consists of five statements. The Particle Theory 1. All matter is made up of very small particles. The Particle Theory 2. There is space between particles. The Particle Theory Particles in a Gas Very far apart; big spaces between particles Move very quickly; move in any direction Have no definite shape or volume; fill up the container they are in Weak attraction between particles Little attraction The Particle Theory Particles in a Liquid Particles are closer together; move more slowly Particles in a liquid are loosely attracted so they slide over each other Liquids have a definite volume, but Little stronger attraction not shape The Particle Theory Particles in a Solid Particles are very close and tightly packed together; particles do not move around Particles in a solid are strongly attracted to each other Strongest attraction Solids have a definite shape and volume The Particle Theory 3. All particles in a pure substance are the same. The Particle Theory A pure substance is a material made up of only one kind of extremely small particle. Each pure substance has its own kind of particle, different in shape and size from the particles of other pure substances. The Particle Theory The white particles in this picture represent sugar, while the blue particles represent water. T The Particle Theory 4. The he Particle in particles Theory matter are always in motion. The Particle Theory When particles are heated, or gain energy, they move faster and the spaces in between them expand in size. The Particle Theory When particles are cooled, or lose energy they move slower and the spaces in between them contract in size. The Particle Theory If the transfer of energy is quite dramatic, the state of matter changes. The Particle Theory Concept Check: What’s the State Change? Sublimation Freezing Evaporation The Particle Theory 5.Particles are attracted to each other. Some particles attract and “stick” to themselves. This is called cohesion. Some particles attract and “stick” to other particles. This is called adhesion. Watch: https://www.usgs.gov/media/videos/adhesion-and- cohesion-water The Particle Theory A substance will dissolve (the particles are broken down so small they are invisible to the naked eye), in another because the particles of each substance are attracted to each other. The Particle Theory Attraction in action: dissolving Water particles are attracted to the sugar particles, making them break apart of solid structure The Particle Theory Water particles and sugar particles mix, and you cannot see them separately. They form a solution (homogenous mixture). The Particle Theory When one substance will not dissolve in another, the substance is said to be insoluble. This is because the particles are not attracted to each Oil and Water other. The Particle Theory When different parts of a mixture can be seen, it is called a heterogeneous Concrete is a mechanical mixture or mechanical because its individual components can be seen. mixture. BOHR RUTHERFORD DIAGRAMS Creating visual representations of atoms Bohr – Rutherford Diagrams Bohr and Rutherford discovered that the electrons of an atom are arranged in energy shells or orbits around the Shell Maximum nucleus. # of e- 1 2 Each orbit has a maximum number of 2 8 electrons that it can hold. 3 8 Bohr Rutherford Diagrams 1. Draw a circle to represent a nucleus. 2. Write protons (p+=___) and number of neutrons (no = ___) inside the circle. 3. Dotted circles represent orbits (electron shells), 4. Draw the electrons by “filling the clock” (12, 3, 6, 9). Start pairing them afterwards. 5. Once the orbit is full, move onto the next until all electrons are accounted for. Example p = 11 n = 23-11 = 12 e = 11 Example p=3 n = 7-3 =4 e=3 Practice Draw B-R diagrams for: B F H Describing Bohr Rutherford Diagrams Electrons can be categorized based on their energy level. Valence electrons: found Core electrons: all other in the furthest energy inner valence electrons level from the nucleus A sodium atom as 1 valence electron in energy level 3, and 10 core electrons, 2 in energy level 1 and 8 in energy level 2. Core electrons The number of core electrons/energy levels affects the size of an atom E.g. sodium is a larger atom than lithium Atomic size affects how reactive an element is Valence electrons Valence electrons are involved in chemical bonding, which involves the transfer or sharing of electrons between atoms. They have more energy than core electrons because they are the furthest from the nucleus. Think like a stretched rubber band flies further than unstretched (more potential energy – potential to move) Enrichment: Why do you think this is? HINT: Think about charges of protons and electrons, force of protons on electrons (law of electric charge), and how that force would be affected by valence electron’s further distance. BOHR RUTHERFORD DIAGRAMS Creating visual representations of atoms Bohr – Rutherford Diagrams Bohr and Rutherford discovered that the electrons of an atom are arranged in energy shells or orbits around the Shell Maximum nucleus. # of e- 1 2 Each orbit has a maximum number of 2 8 electrons that it can hold. 3 8 Bohr Rutherford Diagrams 1. Draw a circle to represent a nucleus. 2. Write protons (p+=___) and number of neutrons (no = ___) inside the circle. 3. Dotted circles represent orbits (electron shells), 4. Draw the electrons by “filling the clock” (12, 3, 6, 9). Start pairing them afterwards. 5. Once the orbit is full, move onto the next until all electrons are accounted for. Example p = 11 n = 23-11 = 12 e = 11 Example p=3 n = 7-3 =4 e=3 Practice Draw B-R diagrams for: B F H Describing Bohr Rutherford Diagrams Electrons can be categorized based on their energy level. Valence electrons: found Core electrons: all other in the furthest energy inner valence electrons level from the nucleus A sodium atom as 1 valence electron in energy level 3, and 10 core electrons, 2 in energy level 1 and 8 in energy level 2. Core electrons The number of core electrons/energy levels affects the size of an atom E.g. sodium is a larger atom than lithium Atomic size affects how reactive an element is Valence electrons Valence electrons are involved in chemical bonding, which involves the transfer or sharing of electrons between atoms. They have more energy than core electrons because they are the furthest from the nucleus. Think like a stretched rubber band flies further than unstretched (more potential energy – potential to move) Enrichment: Why do you think this is? HINT: Think about charges of protons and electrons, force of protons on electrons (law of electric charge), and how that force would be affected by valence electron’s further distance. Determining Subatomic Particles Using the Periodic Table The Periodic Table Invented in the 1800’s by Dmitri Medeleev Arranges chemical elements into rows and columns just like other tables. Rows are called periods Columns are called groups Main group elements are coloured here Transition metals are white https://www.youtube.com/watch?v=fPnwBITSmgU Element Tiles Let’s get to know what the tiles tell you on the table: Atomic Number: Tells you the # of protons in it’s atom Symbol: Either one or two letters, the first always a capital – e.g. Na Some are the first letters of names, while others come from their latin name Atomic Mass: Tells you mass of the atom E.g. O has atomic mass of 16 amu Mass comes from nucleus! Example: Sodium Atomic Number: 11 Symbol: Na Atomic Mass: 22.99 Using Atomic Number and Mass to Determine Atomic Structure Take out your “Build an Atom” worksheet from last week: How many protons and neutrons do each atom have? Compare those values to their atomic number and atomic mass from the periodic table How can you determine the number of protons and neutrons using atomic number and atomic mass? Using Atomic Number and Mass to Determine Atomic Structure #p = AN # of neutrons: atomic mass – atomic number (rounded) Example AN: 11 AM: 23 p = 11 n = 23 – 11 = 12 e=? What about e? You try: Atomic number(AN) = Atomic mass (AM) = p= n= e= What about electrons? Take out your “Build an Atom” worksheet from last week: How many electrons does each atom have? How does this number relate to the number of protons? Why do you think that is? Atoms are neutral! Recall the charge of protons, neutrons, and electrons The number of protons and electrons in an atom are always the same because atoms are neutral! They don’t have a charge. The # of positive protons = # of negative electrons. Atomic Number: 11 Atomic Mass: 23 p = 11 n = 23 – 11 = 12 e = 11 You try it! Look at your periodic table and fill in the chart below Element Element Atomic Atomic # of p # of n # of e Symbol Number Mass (amu) Sulfur Ti 79 126.90