A 0.175 mol sample of N2 gas is contained in a 4.00 L flask at room temperature and pressure. What is the density of the gas, in grams/liter, under these conditions?

As 1 g of (lie radioactive element radium decays over 1 year. k produces 1.161018 alpha particles (helium nuclei). Each alpha particle becomes an atom of helium gas. What is the pressure ¡n pascal of the helium gas produced if it occupies a volume of 125 mL at a temperature of 25 C?

Pyruvic acid, HC3H3O3, is involved in cell metabolism. It can be assayed for (that is, the amount of it determined) by using a yeast enzyme. The enzyme makes the following reaction go to completion: HC3H3O3(aq)C2H4O(aq)+CO2(g) If a sample containing pyruvic acid gives 21.2 mL of carbon dioxide gas, CO2, at 349 mmHg and 30C, how many grams of pyruvic acid are there in the sample?

57 What volume of hydrogen gas, in liters, is produced by the reaction of 3.43 g of iron metal with 40.0 mL of 2.43 M HCl? The gas is collected at 2.25 atm of pressure and 23 C. The other product is FeCl2?

A chemist weighed out 5.14 g of a mixture containing unknown amounts of BaO(s) and CaO(s) and placed the sample in a 1.50-L flask containing CO2(g) at 30.0C and 750. torr. After the reaction to form BaCO3(s) and CaCO3(s) was completed, the pressure of CO2(g) remaining was 230. torr. Calculate the mass percentages of CaO(s) and BaO(s) in the mixture.

2. The volume of a gas sample is 235 mL at a temperature of 25 ℃. At what temperature would that same gas sample have a volume of 310. mL, if the pressure of the gas sample is held constant? −47.0 ℃ 69.4 ℃ 33.1 ℃ 120.℃

Many nitrate salts can be decomposed by heating. For example, blue, anhydrous copper(II) nitrate produces the gases nitrogen dioxide and oxygen when heated. In the laboratory, you find that a sample of this salt produced a 0.195-g mixture of gaseous NO2 and O2 with a total pressure of 725 mm Hg at 35 C in a 125-mL flask (and black, solid CuO was left as a residue). What is the average molar mass of the gas mixture? What are the mole fractions of NO2 and O2 in the mixture? What amount of each gas b in the mixture? Do these amounts reflect the relative amounts of NO2 and O2 expected based on the balanced equation? Is it possible that the fact that some NO2 molecules combine to give N2O4 plays a role? Heating copper(II) nitrate produces nitrogen dioxide and oxygen gas and leaves a residue of copper(ll) oxide.

Which of the following statements is(are) true? a. If the number of moles of a gas is doubled, the volume will double, assuming the pressure and temperature of the gas remain constant. b. If the temperature of a gas increases from 25C to 50C, the volume of the gas would double, assuming that the pressure and the number of moles of gas remain constant. c. The device that measures atmospheric pressure is called a barometer. d. If the volume of a gas decreases by one half, then the pressure would double, assuming that the number of moles and the temperature of the gas remain constant.