4.2 Classifying chemical reactions  (Page 10/34)

Identify the atoms that are oxidized and reduced, the change in oxidation state for each, and the oxidizing and reducing agents in each of the following equations:

(a) $\text{Mg}(s)+{\text{NiCl}}_2(aq)⟶{\text{MgCl}}_2(aq)+\text{Ni}(s)$

(b) ${\text{PCl}}_3(l)+{\text{Cl}}_2(g)⟶{\text{PCl}}_5(s)$

(c) ${\text{C}}_2{\text{H}}_4(g)+3{\text{O}}_2(g)⟶2{\text{CO}}_2(g)+2{\text{H}}_2\text{O}(g)$

(d) $\text{Zn}(s)+{\text{H}}_2{\text{SO}}_4(aq)⟶{\text{ZnSO}}_4(aq)+{\text{H}}_2(g)$

(e) $2{\text{K}}_2{\text{S}}_2{\text{O}}_3(s)+{\text{I}}_2(s)⟶{\text{K}}_2{\text{S}}_4{\text{O}}_6(s)+2\text{KI}(s)$

(f) $3\text{Cu}(s)+8{\text{HNO}}_3(aq)⟶3\text{Cu}{({\text{NO}}_3)}_2(aq)+2\text{NO}(g)+4{\text{H}}_2\text{O}(l)$

Complete and balance the following acid-base equations:

(a) HCl gas reacts with solid Ca(OH) ₂ ( s ).

(b) A solution of Sr(OH) ₂ is added to a solution of HNO ₃ .

Complete and balance the following acid-base equations:

(a) A solution of HClO ₄ is added to a solution of LiOH.

(b) Aqueous H ₂ SO ₄ reacts with NaOH.

(c) Ba(OH) ₂ reacts with HF gas.

Complete and balance the following oxidation-reduction reactions, which give the highest possible oxidation state for the oxidized atoms.

(a) $\text{Al}(s)+{\text{F}}_2(g)⟶$

(b) $\text{Al}(s)+{\text{CuBr}}_2(aq)⟶$ (single displacement)

(c) ${\text{P}}_4(s)+{\text{O}}_2(g)⟶$

(d) $\text{Ca}(s)+{\text{H}}_2\text{O}(l)⟶$ (products are a strong base and a diatomic gas)

Complete and balance the following oxidation-reduction reactions, which give the highest possible oxidation state for the oxidized atoms.

(a) $\text{K}(s)+{\text{H}}_2\text{O}(l)⟶$

(b) $\text{Ba}(s)+\text{HBr}(aq)⟶$

(c) $\text{Sn}(s)+{\text{I}}_2(s)⟶$

Complete and balance the equations for the following acid-base neutralization reactions. If water is used as a solvent, write the reactants and products as aqueous ions. In some cases, there may be more than one correct answer, depending on the amounts of reactants used.

(a) $\text{Mg}{\text{(OH)}}_2(s)+{\text{HClO}}_4(aq)⟶$

(b) ${\text{SO}}_3(g)+{\text{H}}_2\text{O}(l)⟶\text{(assume an excess of water and that the product dissolves)}$

(c) $\text{SrO}(s)+{\text{H}}_2{\text{SO}}_4(l)⟶$

When heated to 700–800 °C, diamonds, which are pure carbon, are oxidized by atmospheric oxygen. (They burn!) Write the balanced equation for this reaction.

The military has experimented with lasers that produce very intense light when fluorine combines explosively with hydrogen. What is the balanced equation for this reaction?

Write the molecular, total ionic, and net ionic equations for the following reactions:

(a) $\text{Ca}{\text{(OH)}}_2(aq)+{\text{HC}}_2{\text{H}}_3{\text{O}}_2(aq)⟶$

(b) ${\text{H}}_3{\text{PO}}_4(aq)+{\text{CaCl}}_2(aq)⟶$

Great Lakes Chemical Company produces bromine, Br ₂ , from bromide salts such as NaBr, in Arkansas brine by treating the brine with chlorine gas. Write a balanced equation for the reaction of NaBr with Cl ₂ .

In a common experiment in the general chemistry laboratory, magnesium metal is heated in air to produce MgO. MgO is a white solid, but in these experiments it often looks gray, due to small amounts of Mg ₃ N ₂ , a compound formed as some of the magnesium reacts with nitrogen. Write a balanced equation for each reaction.

Lithium hydroxide may be used to absorb carbon dioxide in enclosed environments, such as manned spacecraft and submarines. Write an equation for the reaction that involves 2 mol of LiOH per 1 mol of CO ₂ . (Hint: Water is one of the products.)