Question

examine each of the following pairs of potential reactants. use activity series to help you decide whether or not a reaction would occur. write the balanced equation for every reaction. if no reaction occurs, write nr after the balanced reaction.

1. calcium and water
2. rubidium and lithium chloride
3. potassium and aluminum oxide
4. silver and calcium nitrate
5. fluorine and potassium iodide
6. magnesium bromide and chlorine
7. copper and iron(iii) sulfate

match each example of a chemical reaction in column a to the type(s) listed in column b. list all types from column b that apply.

column a\tcolumn b

1. aluminum lawn furniture becomes coated with a layer of aluminum oxide when it sits out in the air.\ta. combustion
2. chlorine gas is bubbled through a calcium bromide solution. the solution turns brown, the color of bromine.\tb. decomposition
3. lime is added to acid water in a lake. water and a salt form.\tc. double-replacement
4. propane is a common household fuel. when burned, water and carbon dioxide are produced.\td. single-replacement
5. steel wool burns, forming an iron oxide.\te. synthesis
6. when an electric current is passed through molten potassium bromide, potassium and bromine form.
7. when solutions of sodium iodide and lead nitrate are combined, a yellow solid forms.

Explanation:

(Problems 8-14):

Step1: Check reactivity, write unbalanced eq

8. Calcium + water:

$\text{Ca}(s) + \text{H}_2\text{O}(l)
ightarrow \text{Ca(OH)}_2(aq) + \text{H}_2(g)$

9. Rubidium + lithium chloride:

$\text{Rb}(s) + \text{LiCl}(aq)
ightarrow \text{RbCl}(aq) + \text{Li}(s)$

10. Potassium + aluminum oxide:

$\text{K}(s) + \text{Al}_2\text{O}_3(s)
ightarrow \text{K}_2\text{O}(s) + \text{Al}(s)$

11. Silver + calcium nitrate:

$\text{Ag}(s) + \text{Ca(NO}_3\text{)}_2(aq)
ightarrow \text{NR}$

12. Fluorine + potassium iodide:

$\text{F}_2(g) + \text{KI}(aq)
ightarrow \text{KF}(aq) + \text{I}_2(s)$

13. Magnesium bromide + chlorine:

$\text{MgBr}_2(aq) + \text{Cl}_2(g)
ightarrow \text{MgCl}_2(aq) + \text{Br}_2(l)$

14. Copper + iron(III) sulfate:

$\text{Cu}(s) + \text{Fe}_2(\text{SO}_4)_3(aq)
ightarrow \text{CuSO}_4(aq) + \text{FeSO}_4(aq)$

Step2: Balance each valid equation

8. Balance H, O:

$\text{Ca}(s) + 2\text{H}_2\text{O}(l)
ightarrow \text{Ca(OH)}_2(aq) + \text{H}_2(g)$

9. Balance all elements:

$2\text{Rb}(s) + 2\text{LiCl}(aq)
ightarrow 2\text{RbCl}(aq) + 2\text{Li}(s)$

10. Balance K, Al, O:

$6\text{K}(s) + \text{Al}_2\text{O}_3(s)
ightarrow 3\text{K}_2\text{O}(s) + 2\text{Al}(s)$

12. Balance K, I, F:

$\text{F}_2(g) + 2\text{KI}(aq)
ightarrow 2\text{KF}(aq) + \text{I}_2(s)$

13. Balance Br, Cl:

$\text{MgBr}_2(aq) + \text{Cl}_2(g)
ightarrow \text{MgCl}_2(aq) + \text{Br}_2(l)$

14. Balance Fe, Cu, sulfate:

$\text{Cu}(s) + \text{Fe}_2(\text{SO}_4)_3(aq)
ightarrow \text{CuSO}_4(aq) + 2\text{FeSO}_4(aq)$

(Problems 15-21):

Step1: Identify reaction type(s)

15. Al + O₂ → Al₂O₃: Synthesis (combining 2 substances)

16. Cl₂ + CaBr₂ → CaCl₂ + Br₂: Single-replacement (Cl replaces Br)

17. Acid + base → salt + water: Double-replacement (neutralization)

18. C₃H₈ + O₂ → CO₂ + H₂O: Combustion (fuel + O₂ → oxides)

19. Fe + O₂ → Fe₃O₄/Fe₂O₃: Synthesis (combining 2 substances) + Combustion (reaction with O₂ to form oxide)

20. KBr → K + Br₂: Decomposition (single compound breaks down)

21. NaI + Pb(NO₃)₂ → PbI₂ + NaNO₃: Double-replacement (ions swap to form precipitate)

Answer:

8. $\text{Ca}(s) + 2\text{H}_2\text{O}(l)

ightarrow \text{Ca(OH)}_2(aq) + \text{H}_2(g)$

9. $2\text{Rb}(s) + 2\text{LiCl}(aq)

ightarrow 2\text{RbCl}(aq) + 2\text{Li}(s)$

10. $6\text{K}(s) + \text{Al}_2\text{O}_3(s)

ightarrow 3\text{K}_2\text{O}(s) + 2\text{Al}(s)$

11. $\text{Ag}(s) + \text{Ca(NO}_3\text{)}_2(aq)

ightarrow \text{NR}$

12. $\text{F}_2(g) + 2\text{KI}(aq)

ightarrow 2\text{KF}(aq) + \text{I}_2(s)$

13. $\text{MgBr}_2(aq) + \text{Cl}_2(g)

ightarrow \text{MgCl}_2(aq) + \text{Br}_2(l)$

14. $\text{Cu}(s) + \text{Fe}_2(\text{SO}_4)_3(aq)

ightarrow \text{CuSO}_4(aq) + 2\text{FeSO}_4(aq)$

15. e. synthesis

16. d. single-replacement

17. c. double-replacement

18. a. combustion

19. a. combustion, e. synthesis

20. b. decomposition

21. c. double-replacement