Q1-1:  Define the word MATTER.

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Q1-2:  Define the word ELEMENT and give an example.

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A1-2: A substance that can not be separated or broken down into simpler substances by chemical means -- Oxygen

Q1-3:  Define the word ATOM and give an example.

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Q1-4:  Define the word MOLECULE and give an example.

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Q1-5:  Define the word COMPOUND and give an example.

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Q1-6:  Define the term CHEMICAL FORMULA and give an example.

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A1-6: A way of representing molecules and compounds that shows the fixed ratio of atoms. -- C₆H₁₂O₆

Q1-7:  Define the word MIXTURE and give an example.

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Q1-8:  State the chemical formulas for:
a) Water; b) Methane; c) Carbon Dioxide; d) Carbon Monoxide

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A1-8:                 a) H₂O
                          b) CH₄
                          c) CO₂
                          d) CO

Q1-9:  What is a HOMOGENOUS MIXTURE?  Give an example.

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Q1-10:  What is a HETEROGENOUS MIXTURE? Give an example.

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Q1-11:  What is a PURE SUBSTANCE?  Give an example.

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A1-11: A sample of matter, either a single element ore a single compound, that has definite chemical and physical properties. -- elements & compounds (H₂  & H₂O)

Q1-12:  Describe a procedure to separate a mixture of salt, finely ground pepper, and pebbles.

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A1-12: Pour the mixture through a filter to remove the larger pebbles. Next, add water to dissolve the salt & then filter out the pepper. Finally, evaporate the water to leave the salt behind.

Q1-13:  You have been asked to prove whether a particular shiny ring is made out of gold or is a fake. How could you use the idea of density to make your decision?

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A1-1:  Measure the mass of the ring. Then, use a graduated cylinder & water to determine the volume in mL. Divide mass by volume to get its density. Gold has a density of 19.3 grams / mL

Q2-1: List 4 physical properties of objects or substances.

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Q2-2: Why are color, volume, and density classified as physical properties?

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Q2-3: Why are flammability and reactivity classified as chemical properties?

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Q2-4: Define MELTING POINT and give the melting point of water.

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Q2-5: Define BOILING POINT and give the boiling point of water.

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A2-5: That point at which a substance turns from a liquid into a gas.
-- 212^oF, 100^oC

Q2-6: Define DENSITY and explain why...
a) a brick is more dense than a sponge.
b) helium-filled balloons float up in the air.
c) a stone sinks to the bottom of a pond.

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Q2-7: Define REACTIVITY.

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Q2-8: Identify the following as physical or chemical properties:
a) reacts with oxygen to form rust; b) is red; c) is shiny and silvery;    d) melts easily; e) boils at 100 degrees celsius; f) is nonflammable;   g) has a low density; h) tarnishes in moist air

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Q2-9: A jar  contains 30mL of glycerin (mass = 37.8g) and 60mL of corn syrup (mass = 82.8 g). Which liquid is the top layer? Explain.

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Q2-10: Calculating Density:
a) A piece of titanium metal has a mass of 67.5 g and a volume of 15 cubic centimeters. What is the density of titanium?

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A2-10: Density = mass / volume
Density = 67.5 g / 15 cm³
Density = 4.5 g / cm³
 

Q2-10: Calculating Density:
b) A sample of a substance that has a mass of 85g has a volume of 110 cubic centimeters. What is the density of the substance? Will the substance float in water?

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A2-10: Density = mass / volume
Density = 85 g / 110 cm³
Density = .772 g/cm³
Will it float? Yes, because water's density is 1 g/cm³

Q3-1: Define the term PHYSICAL CHANGE and give three examples.

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A3-1: A physical change affects one or more physical properties of a substance without changing the identity of the substance. a) adding food coloring to water; b) cutting paper; c) folding paper

Q3-2: Define the term CHEMICAL CHANGE and give three examples.

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A3-2: A chemical change happens when a substance is changed into an entirely NEW substance that has different properties. a) combining iron (magnetic) and sulfur to produce iron sulfide (not magnetic); running electricity through water to produce hydrogen & oxygen; allowing iron (magnetic) to rust (not magnetic).

Q3-3: Name a substance that is NOT flammable. Name a substance that is NOT reactive.

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A3-3: Not flammable: asbestos, CO₂
Not reactive:  Neon, Argon

Q3-4: Explain why changes of state are physical changes.

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A3-4: When water goes from a solid, to a liquid, to a gas -- it is still water, H₂O. It's chemical structure has not changed.

Q3-5: Explain why physical changes can easily be reversed but chemical changes cannot.

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A3-5: Physical changes do not affect the nature of the substance. Chemical changes do affect the nature of the substance.

Q3-6: List three clues that indicate a chemical change has occurred.

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A3-6:   Heat given off (exothermic); heat absorbed (endothermic); bubbles given off (a gas has been produced); a precipitate has formed (something new has dropped out of solution); a color change   

Q3-7: Classify each of the following as a chemical change or a physical change: a) sugar being added to lemonade; b) plants using carbon dioxide and water to form oxygen and sugar; c) water boiling; d) an egg frying; e) rust forming on metal; f) fruit rotting; g) salt being removed from water by evaporation

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A3-7: a) physical; b) chemical; c) physical; d) chemical; e) chemical; f) chemical; g) physical

Q3-8: A light green powder is heated in a test tube. A gas is given off while the solid becomes black.  What type of change is occurring?  Explain your reasoning.

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A3-8: Chemical. The production of a gas is an indication that a new substance has been produced. The change in color from green to black also indicates a chemical change.

Q3-9:
a) Ethanol -- C2H6O     – element? compound? # atoms?
b) Baking Soda -- NaHCO3  element? compound? # atoms?
c) Hydrogen -- H2      – element? compound? # atoms?

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A3-9:
             a) compound -- 9 atoms
             b) compound -- 6 atoms
             c) compound -- 2 atoms

Q3-9:
d) Oxygen -- O2     – element? compound? # atoms?
e) Ozone -- O3      – element? compound? # atoms?
f) Table Salt -- NaCl   – element? compound? # atoms?

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A3-10:
             d) compound -- 2 atoms
             e) compound -- 3 atoms
             f) compound -- 2 atoms

Q3-9:
g) Sulfur -- S     – element? compound? # atoms?
h) Water --  H2O    – element? compound? # atoms?

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A3-11:
             g) element     -- 1 atom
             h) compound -- 3 atoms

Q4-1: Matter can be one of three things. List the 3 possibilities.

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A4-1: element, compound, or a mixture

Q4-2: Elements are made up of one kind of ………

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A4-2: atom

Q4-3: What contains two or more elements that are chemically combined?

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A4-3: compound

Q4-4: Why are mixtures not pure substances?

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A4-4: heterogenous mixtures

Q4-5: List 5 physical properties that can be used to identify substances.

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A4-5: color, mass, melting point, boiling point, and density

Q4-6: List 2 chemical properties of substances.

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A4-6: flammibility and reactivity

Q4-7: What type of change does not alter the identity of the substance?

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A4-7: physical change

Q4-8: When a substance has been altered so that it has different properties, we say it has undergone a …. change.

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A4-8: chemical

Q4-9: How do you separate a MIXTURE?

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A4-9: by physical means

Q4-10: How do you separate a COMPOUND?

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A4-10: by chemical means