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?

One of the ways to remove nitrogen monoxide gas, a serious source of air pollution, from smokestack emissions is by reaction with ammonia gas, NH3. The products of the reaction, N2 and H2O, are not toxic. Write the balanced equation for this reaction. Assign an oxidation number to each element in the reactants and products, and indicate which element is oxidized and which is reduced.

Ethanol, C2H5OH, is a gasoline additive that can be produced by fermentation of glucose. C6H12O62C2H5OH+2CO2 (a) Calculate the mass (g) of ethanol produced by the fermentation of 1.000 lb glucose. (b) Gasohol is a mixture of 10.00 mL ethanol per 90.00 mL gasoline. Calculate the mass (in g) of glucose required to produce the ethanol in 1.00 gal gasohol. Density of ethanol = 0.785 g/mL. (c) By 2022, the U. S. Energy Independence and Security Act calls for annual production of 3.6 1010 gal of ethanol, no more than 40% of it produced by fermentation of corn. Fermentation of 1 ton (2.2 103 lb) of corn yields approximately 106 gal of ethanol. The average corn yield in the United States is about 2.1 105 lb per 1.0 105 m2. Calculate the acreage (in m2) required to raise corn solely for ethanol production in 2022 in the United States.

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)

Nitric acid is produced commercially by the Ostwald process, represented by the following equations: 4NH3(g)+5O24NO(g)+6H2O(g)2NO(g)+O2(g)2NO2(g)3NO2(g)+H2O(l)2HNO3(aq)+NO(g) What mass of NH3 must be used to produce 1.0 106 kg HNO3 by the Ostwald process? Assume 100% yield in each reaction, and assume that the NO produced in the third step is not recycled.

4.106 An ore sample with a mass of 670 kg contains 27.7% magnesium carbonate, MgCO3. If all of the magnesium carbonate in this ore sample is decomposed to form carbon dioxide, describe how to determine what mass of CO2 is evolved during the process.

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.

The sugar sucrose, which is present in many fruits and vegetables, reacts in the presence of certain yeast enzymes to produce ethanol and carbon dioxide gas. Balance the following equation for this reaction of sucrose. C12H22O11(aq) + H2O(l) C2H5OH(aq) + CO2(g)

The formation of water-Insoluble silver chloride is useful in the analysis of chloride-containing substances. Consider the following unbalanced equation: BaCl2(aq) + AgNO3(aq) AgCI(s) + Ba(NO3)2(aq) (a) Write the balanced equation. (b) What mass of AgNO3, in grams, is required for complete reaction with 0.156 g of BaCI2? What mass of AgCI is produced?