For each of the reactions below, classify as a combination, decomposition, single replacement, or double replacement. Zn(s) + H2SO4(aq) ZnSO4(aq) + H2(g)

There are many ionic compounds that dissolve in water to a very small extent. One example is lead(II) chloride. When it dissolves an equilibrium is established between the solid salt and its component ions. Suppose you stir some solid PbCl2 into water. Explain how you would prove that the compound dissolves but to a small extent? Is the dissolving process product-favored or reactant-favored? pbcl2(s)pb2+(aq)+2cl(aq)

Classify each of the following reactions as a combination reaction, decomposition reaction, displacement reaction, or combustion reaction. a When they are heated, ammonium dichromate crystals, (NH4)2Cr2O7, decompose to give nitrogen, water vapor, and solid chromium(III) oxide, Cr2O3. b When aqueous ammonium nitrite, NH4NO2, is heated, it gives nitrogen and water vapor. c When gaseous ammonia, NH3, reacts with hydrogen chloride gas, HCl, fine crystals of ammonium chloride, NH4Cl, are formed. d Aluminum added to an aqueous solution of sulfuric acid, H2SO4, forms a solution of aluminum sulfate, A12(SO4)3. Hydrogen gas is released.

Complete and balance the equations below, and classify them as precipitation, acid-base, gas-forming, or oxidation-reduction reactions. Show states for reactants and products (s, , g, aq). (a) NiCO3 + H2SO4 . (b) Co(OH)2 + HBr (c) AgCH3CO2 + NaCI (d) NiO + CO .

It is stated in Section 6.3 of the text that to balance equations by inspection you start “with the most complicated molecule.” What does this mean? Why is it best to do this?

Copper metal can reduce silver ions to metallic silver. The copper is oxidized to copper ions according to the reaction 2Ag+(aq)+Cu(s)Cu2+(aq)+2Ag(s)A copper strip with a mass of 2.00 g is dipped into a solution of AgNO3. After some time has elapsed, the copper strip is coated with silver. The strip is removed from the solution, dried, and weighed. The coated strip has a mass of 4.18 g. What are the masses of copper and silver metals in the strip? (Hint: Remember that the copper metal is being used up as silver metal forms.)

Classify each of the following reactions as a precipitation, acid-base, or gas forming reaction. Show states for the products (s, , g aq), and then balance the completed equation. Write the net ionic equation. (a) MnCl2(aq) + Na2S(aq) MnS + NaCl (b) K2CO3(aq) + ZnCl2(aq) ZnCO3 + Ka

Sodium thiosulfate, Na2S2O3, is used as a fixer in black-and-white photography. Suppose you have a bottle of sodium thiosulfate and want to determine its purity. The thiosulfate ion can be oxidized with I2 according to the balanced, net ionic equation I2(aq) + 2 S2O32(aq) 2 I(aq) + S4O62 (aq) If you use 40.21 mL of 0.246 M I2 in a titration, what is the weight percent of Na2S2O3 in a 3.232-g sample of impure material?