Exam 2: The Behaviour of Gases

An SUV gets requires 19.6 L of gasoline per 100 km. If the chemical composition can be approximated by C₇H₁₆, with a density of 0.80 g/mL, how many L of CO₂ at 1 bar pressure and 25°C are emitted per km?

If the compressibility factor, pV/nRT, is greater than 1, then

The level of mercury on the sample side of a manometer is 56.0 mm above that of the atmospheric side. If the atmospheric pressure is 103 kPa, what is the pressure of the gas sample (in Torr)?

Consider a sample of gas in a tank. Under which of the following conditions would you expect the most ideal behaviour?

Argon is an important gas, used in many applications where an unreactive gas is needed. If the mole fraction of argon in dry air is 9.34 x 10^-3, how many kg argon can be extracted from 1 km³ dry air at 298K and 1 atm total pressure?

Consider the conversion of methane to acetylene and hydrogen gas shown in the unbalanced reaction below:CH₄ $\rightarrow$ C₂H₂ + H₂What is the final pressure in a 100 L reaction vessel following the conversion of 323 g of methane to acetylene and hydrogen gases at 1725°C?

Use the concept of partial pressures in gas mixtures.

The level of mercury on the sample side of a manometer is 56.0 mm above that of the atmospheric side. If the atmospheric pressure is 1.05 bar, what is the pressure of the gas sample (in Torr)?

The pressure in an underwater dwelling is 9.52 atm. What is the pressure in Torr and Pascals?

The density of air at room temperature and pressure (1 atm) is about 1.16 g/L. Other gases have different vapour densities and may be less dense than air (such as helium) or more dense (propane). Gases with vapour densities greater than air mix slowly with air (because on average, the molecules have smaller velocities) and collect in low-lying areas. In Bhopal, India, a large quantity of methyl isocyanate, CH₃OCN, escaped from a storage tank killing thousands of people. Calculate the vapour density of methyl isocyanate at room temperature and pressure.

If the rate of effusion of Kr is 3 x 10^-5 moles/s and the rate of effusion of an unknown gas under identical conditions is 4.3 x 10^-5 moles/s, what is the identity of the unknown gas?

Which of the following molecules/atoms will exert a greater force when it strikes the wall of the container under ideal conditions?

A 400 L steel tank is filled with a mixture of 20 kg of methane (CH₄), 5 kg of ethane (C₂H₆) and 0.050 g of butanethiol (C₄H₁₀S). (This last sulphur-containing compound has an intense smell to indicate any leaks of this flammable mixture). Determine the composition of the gas in terms of mole fraction and ppm.

The concentration of an old solution of hydrogen peroxide is being tested because hydrogen peroxide decomposes over time. The following reaction is catalyzed by potassium iodide and used to determine the concentration. If 3.0 ml of the peroxide solution is tested and produces 55 ml of O_2(g) at 750 mm Hg and 23°C, how many grams of hydrogen peroxide were in the solution? 2 H₂O_2(aq) $\rarr$ 2 H₂O_(l) + O_2(g)

A mylar novelty balloon is filled with 4.5 L of He at 1 atm pressure and 23°C temperature. It is then dipped into a liquid nitrogen (77K) until the gas and balloon are at 77K. What is the volume of the balloon at 77K?

A spherical weather balloon is constructed so that the gas inside can expand as the balloon ascends to higher altitudes where the pressure is lower. If the radius of the spherical balloon is 2.5 m at sea level where the pressure is 753 Torr, what will be the radius at an altitude of about 10 km where the pressure of the gas is 210 Torr if the temperature has not changed?

Understand gas pressure and express pressure in various units.

A sample of N₂ gas is contaminated with one of the noble gases. It is found that the contaminant effuses at 1.87 times the rate of N₂. What is the contaminating noble gas?

An automobile tire has a volume of about 42 L. How many moles of air are contained in such a tire at a pressure of 220 kPa at a temperature of 28°C?

A researcher is studying the rate of consumption of CO₂ by some plants in a sealed container. If the plants are the major use and source of gases is by the following photosynthesis reaction, what does the researcher need to be concerned about as the reaction proceeds? 6 CO_2(g) + 6 H₂O_(l) $\rarr$ C₆H₁₂O_6(s) + 6 O_2(g)