UNIT 5: CHEMICAL REACTIONS STUDY GUIDE

Multiple choice:

____1. Chemical reactions _____.

a. simply change the form or state of the reactants.

b. create new atoms.

c. always produce new substances.

d. create more matter than what they started with.

____2. Which of the following is the correct skeleton equation for the combination of solid zinc with liquid bromine to produce solid zinc bromide?

a. Zn2(s) + Br(l) à ZnBr2(s)

b. Zn(s) + Br2(l) à ZnBr2(s)

c. Zn(s) + Br2(aq) à ZnBr2(s)

d. ZnBr2(s) à Zn(s) + Br2(l)

____3. A substance that is needed to speed up a reaction but is not a product or a reactant is known as a ____.

a. catalyst b. coefficient c. spectator ion d. steroid

____4. In a combustion reaction, one of the reactants is always ____.

a. a liquid b. water c. a metal d. oxygen

____5. Which of the following statements is true about the decomposition of a simple binary compound?

a. The products cannot be predicted.

b. The reactant is a single substance.

c. The reactant must always be a molecular substance.

d. The product is a single substance.

____6. The equation 2P2O5 à 4P + 5O2 is an example of which type of reaction?

a. double replacement c. decomposition e. synthesis

b. single replacement d. combustion

____7. The equation CH4 + 2O2 à CO2 + 2H2O is an example of which type of reaction?

a. double replacement c. decomposition e. synthesis

b. single replacement d. combustion

____8. The equation: 2Na + Cl2 à 2NaCl is an example of which type of reaction?

a. double replacement c. decomposition e. synthesis

b. single replacement d. combustion

9. List 5 observations that, when seen, usually indicate a chemical change has occurred:

1.

2.

3.

4.

5.

Complete the following equations by predicting what products will form. Make sure you balance each equation when finished.

SINGLE REPLACEMENT: (Honors chem must also predict any equations that are no reactions).

10. F2 + CuCl2 à

11. Hg + CaSO4 à

12. Sn + Mg(ClO3)2 à

13. Zn + H2SO4 à

14. K + HOH à

DOUBLE REPLACEMENTS: (Honors chem should mark all precipitates with a downward arrow and write net ionic equations for those reactions that happen).

15. Pb(NO3)2 + K2S à

16. MgCl2 + AgNO3 à

17. KOH + H3PO4 à

18. MgI2 + KClO3 à

19. (NH4)2SO4 + CaI2 à

COMBUSTION REACTIONS:

20. C10H22 + O2 --Δ->

21. C2H2 + O2 --Δ->

Write balanced chemical equations for the following chemical changes. Be sure to include all phase notation and indicate the catalyst where appropriate.

21. Calcium metal is moderately reactive. If solid turnings of calcium metal are added to water, the metal begins to bubble. Hydrogen gas is formed and the water begins to turn cloudy as relatively insoluble calcium hydroxide also forms as the temperature of the reaction increases.

22. Magnesium hydroxide solution has been used for many years as an antacid (“milk of magnesia”) because it reacts with the solution of hydrochloric acid in the stomach, producing aqueous magnesium chloride and water.