In the presence of oxygen, diborane undergoes combustion to produce diboron trioxide, water, and enough energy to propel a rocket. B₂H (1) + 302(g) -> B₂O3(s) + 3H2O(g) Calculate the mass of H2O formed when 284. g of B2H6 reacts using the balanced equation. Be sure your answer has the correct number of significant figures. ☐ g H₂O x10

Ammonia can be formed by a direct reaction of nitrogen and hydrogen. N2(g) + 3 H2(g) 2 NH3(g) A tiny portion of the starting mixture is represented by the diagram, where the blue circles represent N and the white circles represent H. Which of these represents the product mixture? For the reaction of the given sample, which of these statements is true? (a) N2 is the limiting reactant. (b) H2 is the limiting reactant. (c) NH, is the limiting reactant. (d) No reactant is limiting: they are present in the correct stoichiometric ratio.

In an experiment designed to produce calcium oxide by the chemical reaction 2Ca + O2 2CaO 177.2 g of CaO was obtained out of a possible 203.9 g ofCaO. a. What is the theoretical yield of CaO? b. What is the actual yield of CaO? c. What is the percent yield of CaO?

3.115 The average person exhales 1.0 kg of carbon dioxide in a day. Describe how you would estimate the number of CO2 molecules exhaled per breath for this average person.

You react nitrogen and hydrogen in a container to produce ammonia, NH3(g). The following figure depicts the contents of the container after the reaction is complete. a Write a balanced chemical equation for the reaction. b What is the limiting reactant? c How many molecules of the limiting reactant would you need to add to the container in order to have a complete reaction (convert all reactants to products)?

In a blast furnace at high temperature, iron(III) oxide in ore reacts with carbon monoxide to produce metallic iron and carbon dioxide. The liquid iron produced is cooled and weighed. The reaction is run repeatedly with the same initial mass of iron(III) oxide, 19.0 g, but differing initial masses of carbon monoxide. The masses of iron obtained arc shown in this graph. (a) Write the balanced chemical equation for this reaction. (b) Calculate the mass of CO required to react completely with 19.0 g iron(III) oxide. (c) Calculate the mass of carbon dioxide produced when the reaction converts 10.0 g iron(III) oxide completely to products. (d) From the graph, determine which reactant is limiting when less than 10.0 g carbon monoxide is available to react with 19.0 g iron(III) oxide. (e) From the graph, determine which reactant is limiting when more than 10.0 g carbon monoxide is available to react with 19.0 g iron(III) oxide. (f) Calculate the percent yield if 24.0 g iron(III) oxide reacted with 20.0 g carbon monoxide to produce 15.9 g metallic iron. (g) Calculate the minimum mass of additional limiting reactant required to react with all of the excess of nonlimiting reactant from part (f).

3.81 The particulate scale drawing shown depicts the products of a reaction between H2 and O2 molecules. (a) Draw a similar representation for the reactants that must have been present before the reaction took place. (b) Write a balanced chemical equation for the reaction, using the smallest possible whole number coefficients.

3.75 The following pictures show a molecular-scale view of a chemical reaction between the compounds AB2 and B2. (A atoms are shown in blue and B atoms in white). 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 reac- tion has gone to completion. Write a balanced chemical equation for this reaction. As usual, your equation should use the smallest possible whole number coefficients for all substances.

4.70 The particulate scale drawing shown depicts the products of a reaction between H2 and O2 molecules. (a) Draw a similar representation for the reactants that must have been present before the reaction took place. (b) Write a balanced chemical equation for the reaction, using the smallest possible whole number coefficients. (c) identify the limiting reactant, and explain how the pictures allow you to do so.

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.