Chapter 1, Problem 1.127E

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.

Without consulting your textbook, list and explain the main postulates of the kinetic molecular theory for gases. How do these postulates help us account for the following bulk properties of a gas: the pressure of the gas and why the pressure of the gas increases with increased temperature; the fact that a gas tills its entire container; and the fact that the volume of a given sample of gas increases as its temperature is increased.

A power plant is driven by the combustion of a complex fossil fuel having the formula C11H7S. Assume the air supply is composed of only N2 and O2 with a molar ratio of 3.76:1.00, and the N2 remains unreacted. In addition to the water produced, the fuels C is completely combusted to CO2 and its sulfur content is converted to SO2. In order to evaluate gases emitted at the exhaust stacks for environmental regulation purposes, the nitrogen supplied with the air must also be included in the balanced reactions. a Including the N2 supplied m the air, write a balanced combustion equation for the complex fuel assuming 100% stoichiometric combustion (i.e., when there is no excess oxygen in the products and the only C-containing product is CO2). Except in the case of N2, use only integer coefficients. b Including N2 supplied in the air, write a balanced combustion equation for the complex fuel assuming 120% stoichiometric combustion (i.e., when excess oxygen is present in the products and the only C-containing product is CO2). Except in the case of use only integer coefficients c Calculate the minimum mass (in kg) of air required to completely combust 1700 kg of C11H7S. d Calculate the air/fuel mass ratio, assuming 100% stoichiometric combustion. e Calculate the air/fuel mass ratio, assuming 120% stoichiometric combustion.

You wish to prepare 1 L of a 0.02-M potassium iodate solution. You require that the final concentration be within 1% of 0.02 M and that the concentration must be known accurately to the fourth decimal place. How would you prepare this solution? Specify the glassware you would use, the accuracy needed for the balance, and the ranges of acceptable masses of KIO3 that can be used.

A soft drink contains an unknown mass of citric acid, C3H5O(COOH)3. It requires 6.42 mL of 9.580 × 10−2-M NaOH to neutralize the citric acid in 10.0 mL of the soft drink. C3H5O(COOH)3(aq) + 3 NaOH(aq) → Na3C3H5O(COO)3(aq) + 3 H2O(ℓ) Determine which step in these calculations for the mass of citric acid in 1 mL soft drink is incorrect? Why? n (NaOH) = (6.42 mL)(1L/1000 mL)(9.580 × 10−2 mol/L) n (citric acid) = (6.15 × 10−4 mol NaOH) × (3 mol citric acid/1 mol NaOH) m (citric acid in sample) = (1.85 × 10−3 mol citric acid) × (192.12 g/mol citric acid) m (citric acid in 1 mL soft drink) = (0.354 g citric acid)/(10 mL soft drink) Determine the correct result.

What is true about the chemical properties of the product? a. The properties are more like chemical A. b. The properties are more like chemical B. c. The properties are an average of those of chemical A and chemical B. d. The properties are not necessarily like either chemical A or chemical B. e. The properties arc more like chemical A or more like chemical B, but more information is needed. Justify your choice, and for choices you did not pick, explain what is wrong with them.

94. Baking soda (sodium hydrogen carbonate. NaHCO3) is often used to neutralize spills of acids on the benchtop in the laboratory. What mass of NaHCO3 would be needed to neutralize a spill consisting of 25.2 mL of 6.01 M hydrochloric acid solution?

A student wants to prepare 1.00 L of a 1.00-M solution of NaOH (molar mass = 40.00 g/mol). If solid NaOH is available, how would the student prepare this solution? If 2.00 M NaOH is available, how would the student prepare the solution? To help ensure three significant figures in the NaOH molarity, to how many significant figures should the volumes and mass be determined?

Use the web to determine the differences in the amounts of aluminum recycled in states where there are deposits on aluminum cans versus states where recycling is voluntary. What is the most reliable way to estimate this value? mat uncertainty is there in the estimate?