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Unit 6: Properties of Matter Ch 16 – What is Matter? Unit Six: Properties of Matter • 16.1 Classifying Matter • 16.2 Measuring Matter • 16.3 States of Matter Chapter 16 Learning Goals • Classify samples of matter from everyday life as heterogeneous mixtures, homogeneous mixtures, compounds, or elements. • Measure volume using the displacement technique. • Measure mass with scales and balances. • Use an indirect technique to infer mass from density measurements. • Identify the states of matter. • Classify the states of matter in order of energy. • Recognize changes in state as a physical change in matter. • Explain the states of matter in terms of molecular motion. Chapter 16 Vocabulary Terms • • • • • • atom compounds elements heterogeneous mixture homogeneous mixture law of conservation of mass • • • • matter mixtures molecule substances I. What is matter? A. Chemistry 1. the study of matter and how it changes B. Matter 1. anything that takes up space and has mass a. mass 1) measure of the quantity of matter in an object b. weight 1) the force with which gravity pulls on a quantity of matter 2. Atom a. the smallest particle that has the properties of an element b. elements are made up of atoms C. Pure Substance 1. any matter that has a fixed composition and definite properties 2. elements and compounds 3. Element a. a substance that cannot be broken down into simpler substances b. ie – Periodic Table of the Elements 4. Compound a. substance made of atoms of more than one element bound together b. nylon – not an element – made up of atoms – contains hundreds of C, H, N, O atoms c. Compounds are unique and possess properties unlike the elements that they make up 1) ie – H, O, N are gases - you can’t see them - nylon is a flexible solid 5. A Molecule acts as a unit a. the smallest unit of a substance that exhibits all the properties characteristic of that substance b. ie – molecule of water – 2 H, 1 O bonded together 6. Chemical formulas represent compounds and molecules a. chemical formula 1) the chemical symbols and numbers indicating the atoms contained in the basic unit of a substance b. ie – C11C22O11 - 1 molecule of table sugar - 11 C atoms, 22 H atoms, 11 O atoms - 3 C11C22O11 - 3 molecules of sugar D. Mixture 1. a combination of more than one pure substance a. salad b. grape juice – mixture of water, acids, sugars, vitamins c. almost everything we eat d. air e. polyester/cotton shirts 2. Mixtures are classified by how thoroughly the substances mix a. homogeneous mixture 1) homo – same 2) mixing occurs between the individual units and is the same throughout 3) Examples a) salt water – salt will not settle out b) carbonated drinks 4) Also known as a solution a) solute (1) what is being dissolved b) solvent (1) what the solute is being dissolved in 5) Other examples – kool-aid, soda, syrup, coffee, tea b. Heterogeneous Mixture 1) hetero – different 2) substances are not uniformly mixed (don’t dissolve) 3) flour and water – flour will settle out 4) Types a) Colloids (1) never settles (2) scatters light (3) ie – milk, gelatin, mayonnaise b) Suspensions (1) liquid in which visible particles settle out (2) scatters light until particles settle out (3) ie – muddy water, liquid antibiotic, Italian dressing 5) Two samples of a heterogeneous mixture could be different c. Mixtures can be separated by physical means 1) sorting 2) filtering 3) heating 4) cooling d. Miscible 1) describes two or more liquids that are able to dissolve into each other in various proportions 2) ie – gasoline – 100’s of compounds uniformly mixed together – is homogeneous mixture e. Immiscible 1) describes two or more liquids that do not mix into each other 2) ie – oil and water – can see two layers MATTER PURE SUBSTANCES Elements Compounds MIXTURES Heterogeneous Homogeneous mixtures mixtures Element Compound Homogeneous Mixture Heterogeneous Mixture Element - A substance that contains only one type of atom - ie – copper metal - Aluminum metal - Oxygen gas - Hydrogen gas Compound A substance that contains more than one type of atom ie – water Carbon dioxide Table salt Homogeneous Mixture A mixture that contains more than one type of matter and is the same throughout ie – soda pop, air, chocolate ice cream Heterogeneous Mixture A mixture that contains more than one type of matter and is not the same throughout ie – chicken soup, soil, fudge ripple ice cream 16.1 Classifying Matter Key Question: How can a homogenous mixture be separated? 16.1 Investigation Results Ink color black blue green Distance Dye colors traveled by present dye (Dc) Distance traveled by water (Dw) Retention Factor (Dc/Dw) blue 5.9 cm 0.84 pink/purple 5.0 cm yellow 3.4 cm 0.49 blue 5.8 cm 0.89 pink/purple 5.0 cm blue 6.0 cm yellow 3.7 cm 7.0 cm 6.5 cm 6.5 cm 0.71 0.77 0.92 0.57 II. Measuring Matter A. Measuring volume 1. Read volume marks at eye level for accuracy 2. Meniscus B. Types of Data 1. quantitative data a. numbers b. ie- 2,457 meters, 87 seeds germinated 2. qualitative data a. descriptive (adjectives) b. ie – a long distance, dark green, plant B is taller than plant A C. accuracy 1. number that is close to the true value D. precision 1. number that is as exact as possible (ie – 47.452134 cm) Not Accurate Accurate C. accuracy 1. number that is close to the true value D. precision 1. number that is as exact as possible (ie – 47.452134 cm) and repeated Precise Not Accurate Precise Accurate E. Measuring volume 1. You can calculate volume of solids using formulas 16.2 Measuring Matter Key Question: How is matter measured? III. States of Matter A. molecule 1. the smallest possible particle of a compound that retains the properties of the compound B. Atom 1. smallest possible particle of an element C. States of Matter 1. Solid a. atoms are held tightly together b. rigid structure c. have a definite shape and volume 2. Liquid a. atoms are held tightly together, but can still slide past each other b. take on the shape of their container 3. Gas a. atoms are constantly in motion b. expands to fill the available space c. gases can exert pressure 1) Pressure a) the force exerted on a unit area of a surface b) fill a balloon with air – the pressure will increase – let go and the balloon will fly through the air as the pressurized gas escapes 4. Plasma a. make up the majority of outer space b. atoms break apart losing electrons when heated to high temperatures (ie – 10,000 degrees) Four States of Matter Plasma is found in the core of our sun and stars. http://www.its.caltech.edu/~ccc/participants/volunteers/States-of-Matter.pdf D. Changes in State 1. melting 2. evaporation 3. freezing 4. condensation 5. sublimation 6. deposition • Changes of state at 1 atm of pressure (normal pressure at sea level) 16.3 States of Matter Key Question: How fast can you melt an ice cube? 16.3 Investigation Results Average Kinetic Energy Over Time Temp (degrees C) 25.0 20.0 15.0 10.0 5.0 0.0 0.0 5.0 10.0 Time (min) 15.0 20.0 E. Energy 1. the ability to do work/working/moving matter 2. energy is transferred in all changes of state a. heat energy is released to the environment 1) condensation 2) freezing 3) deposition b. heat energy is taken from the environment 1) melting 2) evaporation 3) sublimation apollo.lsc.vsc.edu 3. changing state does not change composition or mass 4. Law of Conservation of Mass a. Mass cannot be created or destroyed b. ie – burned up match – looks smaller, but the mass was not destroyed – the mass of the reactants (match and oxygen) is the same as the mass of the products (ash, smoke, gases) 5. Law of Conservation of Energy a. Energy cannot be created or destroyed b. the energy can change from one form to another apollo.lsc.vsc.edu E. Kinetic Theory 1. all matter is made of atoms and molecules that act like tiny particles 2. these tiny particles are always in motion – the higher the temperature, the faster the particles move 3. At the same temperature, more massive (heavier) particles move slower than less massive (lighter) particles - Describe the smell when you walk into a bakery or walk into the kitchen when supper is being prepared Hi