Question

127 chemistry prep b unit 1 ch. 3 test multiple choice: read each question carefully. select the letter of the choice that best answers the question or completes the statement. mark your letter choice on the scan - sheet. (1 pt each) 1. which of the following is evidence that a chemical reaction occurred? a. color change b. light production c. cutting in half d. both a and b 2. which of the following in an extensive property? a. density b. color c. volume d. temperature 3. the substances combined in a chemical reaction are known as a. products b. compounds c. reactants d. mixture 4. the change from a liquid to a solid is called a. sublimation b. freezing c. melting d. condensation 5. what is required for a substance to change phases? a. conservation b. melting c. freezing d. energy 6. which of these is not a method name for separating the components of a mixture? a. filtration b. sublimation c. burning d. distillation 7. which of the following in a physical change? a. digesting a cookie b. baking a cake c. melting chocolate d. burning wood 8. when working in a lab room, violet colored vapor appears when solid iodine crystals are heated. this is an example of what state change? a. melting b. freezing c. boiling d. condensing e. sublimation 9. which of these is not a chemical property of paper? a. flammability b. color change c. mass d. decomposed 10. matter is defined as a. the mass of an object b. energy in motion c. stuff all around us d. anything that has mass and takes up space 11. which of the following is a physical property of water? a. has a boiling point of 100°c b. odorless/colorless liquid c. reactivity with metals d. a and b 12. which characteristic is unique and only applies to the gas state? a. definite volume b. easily compressed c. tightly packed particles d. definite shape 13. a phase of matter that is described as having a definite shape and volume is a. solid b. liquid c. gas d. all of the above 14. which of the following is not considered to be a pure substance? a. water (h₂o) b. iron metal (fe) c. carbon monoxide (co) d. air 15. an example of a change of state is a. straining pasta from water b. boiling water on the stove c. shaking water in a bottle d. spraying water from a hose matching: select the definition/description that best matches the term in the 1st column. (1 pt each) 16. mixture a. also known as a chemical reaction 17. physical change b. mass of the reactants must be the same as the mass of the products 18. chemical change c. traits that do not depend on the amount of the substance 19. solution d. homogeneous mixture 20. element e. simplest form of matter with a unique set of properties 21. physical intensive ab. two or more pure substances not chemically combined 22. physical extensive ac. alters a substance without changing its composition 23. law of conservation of mass ad. traits that do depend on how much of the substance there is

Explanation:

Step1: Recall chemical - reaction evidence

Color change and light production can indicate a chemical reaction. Cutting in half is a physical change. So the answer to question 1 is d. Both a and b.

Step2: Understand extensive property

An extensive property depends on the amount of substance. Volume is an extensive property while density, color and temperature are intensive properties. So the answer to question 2 is c. Volume.

Step3: Know chemical - reaction terms

The substances combined in a chemical reaction are reactants. So the answer to question 3 is c. Reactants.

Step4: Recall phase - change terms

The change from a liquid to a solid is freezing. So the answer to question 4 is b. Freezing.

Step5: Identify phase - change requirement

Energy is required for a substance to change phases. So the answer to question 5 is d. Energy.

Step6: Recognize mixture - separation methods

Filtration, sublimation and distillation are methods to separate mixtures. Burning is a chemical reaction, not a separation method. So the answer to question 6 is c. Burning.

Step7: Distinguish physical and chemical changes

Melting chocolate is a physical change as it only changes the state. Digesting a cookie, baking a cake and burning wood are chemical changes. So the answer to question 7 is c. Melting chocolate.

Step8: Identify iodine state - change

When solid iodine crystals are heated and violet - colored vapor appears, it is sublimation. So the answer to question 8 is e. Sublimation.

Step9: Differentiate chemical and physical properties

Mass is a physical property. Flammability, color change during a reaction and decomposition are chemical properties. So the answer to question 9 is c. Mass.

Step10: Recall matter definition

Matter is anything that has mass and takes up space. So the answer to question 10 is d. anything that has mass and takes up space.

Step11: Identify water physical properties

Having a boiling point of 100°C and being an odorless/colorless liquid are physical properties of water. Reactivity with metals is a chemical property. So the answer to question 11 is d. A and B.

Step12: Determine gas - state characteristic

Gases are easily compressed. They do not have a definite volume or shape and their particles are not tightly packed. So the answer to question 12 is b. easily compressed.

Step13: Recall matter - phase characteristics

Solids have a definite shape and volume. So the answer to question 13 is a. Solid.

Step14: Distinguish pure substances

Air is a mixture of different gases and is not a pure substance. Water, iron metal and carbon monoxide are pure substances. So the answer to question 14 is d. Air.

Step15: Identify state - change example

Boiling water on the stove is a change of state (from liquid to gas). Straining pasta from water is a separation process, shaking water in a bottle is a physical movement and spraying water from a hose is a physical action. So the answer to question 15 is b. boiling water on the stove.

Step16: Match 'Mixture'

A mixture is two or more pure substances not chemically combined. So 16 matches AB.

Step17: Match 'Physical change'

A physical change alters a substance without changing its composition. So 17 matches AC.

Step18: Match 'Chemical change'

A chemical change is also known as a chemical reaction. So 18 matches A.

Step19: Match 'Solution'

A solution is a homogeneous mixture. So 19 matches D.

Step20: Match 'Element'

An element is the simplest form of matter with a unique set of properties. So 20 matches E.

Step21: Match 'Physical Intensive'

Physical intensive properties are traits that do not depend on the amount of the substance. So 21 matches C.

Step22: Match 'Physical Extensive'

Physical extensive properties are traits that DO depend on how much of the substance there is. So 22 matches AD.

Step23: Match 'Law of Conservation of Mass'

The law of conservation of mass states that the mass of the reactants must be the same as the mass of the products. So 23 matches B.

Answer:

1. d. Both a and b
2. c. Volume
3. c. Reactants
4. b. Freezing
5. d. Energy
6. c. Burning
7. c. Melting chocolate
8. e. Sublimation
9. c. Mass
10. d. anything that has mass and takes up space
11. d. A and B
12. b. easily compressed
13. a. Solid
14. d. Air
15. b. boiling water on the stove
16. AB. Two or more pure substances not chemically combined
17. AC. Alters a substance without changing its composition
18. A. Also known as a chemical reaction
19. D. Homogeneous mixture
20. E. Simplest form of matter with a unique set of properties
21. C. Traits that do not depend on the amount of the substance
22. AD. Traits that DO depend on how much of the substance there is
23. B. Mass of the reactants must be the same as the mass of the products