Identify the reactants and products in a chemical equation, and complete the tables to indicate how many atoms of each type of element are present on either side of the following equations. C5H12 (l) +8O2 (g) --> 5CO2 (g) + 6HO (g)

Iron forms a sulfide with the approximate formula Fe7S8. Assume that the oxidation state of sulfur is 2 and that iron atoms exist in both +2 and +3 oxidation states. What is the ratio of Fe(II) atoms to Fe(III) atoms in this compound?

4.8 In an experiment carried out at very low pressure, 13x1015 molecules of H2 are reacted with acetylene, C2H2, to form ethane, C2H6, on the surface of a catalyst. Write a balanced chemical equation for this reaction. How many molecules of acetylene are consumed?

The carbon dioxide exhaled in the breath of astronauts is often removed from the spacecraft by reaction with lithium hydroxide 2LiOH(s)+CO2(g)Li2CO3(s)+H2O(l) Estimate the grams of lithium hydroxide required per astronaut per day. Assume that each astronaut requires 2.50 103 kcal of energy per day. Further assume that this energy can be equated to the heat of combustion of a quantity of glucose, C6H12O6, to CO2(g) and H2O(l). From the amount of glucose required to give 2.50 103 kcal of heat, calculate the amount of CO2 produced and hence the amount of LiOH required. The H for glucose(s) is 1273 kJ/mol.

Nitrogen gas (N2) and hydrogen gas (H2) react to form ammonia gas (NH3). Consider the mixture of N2 () and H2 () in a closed container as illustrated below: Assuming the reaction goes to completion, draw a representation of the product mixture. Explain how you arrived at this representation.

3.88 One Step in the enrichment of uranium for use in nuclear power plants involves the reaction of UO2 with hydro- fluoric acid (HF) solution. The products are solid UF4 and water. Write a balanced chemical equation for this reaction.

High cost and limited availability of a reactant often dictate which reactant is limiting in a particular process. Identify the limiting reactant when the reactions below are run, and come up with a reason to support your decision. a. Burning charcoal on a grill: C(s)+O2(g)CO2(g) b. Burning a chunk of Mg in water: Mg(s)+2H2O(l)Mg(OH)2(aq)+H2(g) c. The Haber process of ammonia production: 3H2(g)+N2(g)2NH3(g)

4.19 How many metric tons of carbon are required to react with 7.83 metric tons of Fe2O3 according to the following reaction? 2Fe2O3+3C3CO2+4Fe How many metric tons of iron are produced?

4.69 The pictures below show a molecular-scale view of a chemical reaction between H2 and CO to produce methanol, CH3OH. The box on the left represents the reactants at the instant of mixing, and the box on the right shows what is left once the reaction has gone to completion. Was there a limiting reactant in this reaction? If so, what was it? Write a balanced chemical equation for this reaction. As usual, your equation should use the smallest possible whole number coefficients for all substances.

Silicon is produced for the chemical and electronics industries by the following reactions. Give the balanced equation for each reaction. a. SiO2(s)+C(s)arefurnaceElectricSi(s)+CO(g) b. Liquid silicon tetrachloride is reacted with very pure solid magnesium, producing solid silicon and solid magnesium chloride. c. Na2SiF6(s) + Na(s) Si(s) + NaF(s)