Question 1

If a slow leak in an inner tube has reduced the volume of the tube to one-third its original inflated volume,this means that one-third of the moles of gas have escaped the tube.(Assume constant temperature and pressure. )

Accepted Answer

According to the ideal gas law (PV=nRT), at constant temperature and pressure, the volume of a gas is directly proportional to the number of moles of the gas. If the volume of the tube is reduced to one-third its original volume, it means that two-thirds of the moles of gas have escaped, not one-third.

Question 2

Vapor pressure of water increases with increasing temperature because the higher temperature causes more water molecules to evaporate.

Accepted Answer

This is because at higher temperatures, the kinetic energy of the water molecules increases, leading to more collisions between molecules and the escape of more water molecules into the vapor phase.

Question 3

One mole of F₂ gas at STP would take up twice the volume of one mole of Ar gas at STP.

Accepted Answer

The volume of a gas at STP is directly proportional to the number of moles of the gas, assuming constant pressure and temperature. Therefore, one mole of any gas at STP takes up the same volume as one mole of any other gas at STP.

Question 4

If you had a five liter balloon of argon gas and a five liter balloon of xenon gas,and you removed 10 grams of gas from each balloon,the balloons would both shrink down to the same size.

Accepted Answer

The amount by which each balloon shrinks depends on the molar mass of the gas and the amount (in moles) removed, not just the weight. Argon and xenon have different molar masses, so removing the same mass of each gas would remove different amounts of moles, leading to different final volumes.

Question 5

For all gas law calculations,the temperature must be in kelvins.

Accepted Answer

This is true, as the gas laws require temperature to be expressed in kelvins for accurate calculations.

Question 6

If the kelvin temperature of a gas is doubled,the volume is doubled provided that the pressure and the number of particles remains constant.

Accepted Answer

According to Charles's Law, the volume of a gas is directly proportional to its temperature in kelvins if the pressure and the number of particles of the gas remain constant. Therefore, if the temperature is doubled, the volume also doubles.

Question 7

If the number of gas particles is halved,the volume of the gas will be halved given that the temperature and pressure do not change.

Accepted Answer

The answer of If the number of gas particles is...

Question 8

The molar volume of any gas at conditions of standard temperature and pressure is 22.4 liters.

Accepted Answer

This is known as Avogadro's Law, which states that equal volumes of gases at the same temperature and pressure contain the same number of particles, which is why the molar volume is always the same at standard temperature and pressure.

Question 9

"Molar Mass" can be calculated using the formula: Molar mass =  
.

Accepted Answer

The formula to calculate molar mass is not provided.

Question 10

The volume of a gas and the number of particles is inversely proportional.

Accepted Answer

The volume of a gas and the number of particles are directly proportional according to Avogadro's law, which states that equal volumes of gases at the same temperature and pressure contain an equal number of particles.

Question 11

Using pure oxygen in scuba diving tanks is a good method of preventing the nitrogen bends.

Accepted Answer

Using pure oxygen in scuba diving tanks would actually increase the risk of oxygen toxicity. To prevent the nitrogen bends, divers use a decompression schedule or make safety stops during the ascent to allow nitrogen to safely exit their body.

Question 12

If the number of gas particles is tripled,the volume will be 1/3 of the original given that temperature and pressure do not change.

Accepted Answer

According to Avogadro's law, at constant temperature and pressure, the volume of a gas is directly proportional to the number of gas particles. Therefore, if the number of gas particles is tripled, the volume will also triple.

Question 13

Dalton's law of partial pressure is: P =  
.

Accepted Answer

The answer of Dalton's law of partial pressure is: P...

Question 14

The vapor pressure of water is independent of temperature.

Accepted Answer

The vapor pressure of water increases with temperature, therefore it is not independent of temperature.

Question 15

Aerosol spray cans contain gas trapped in a fixed volume and cans of this type can explode if heated to high temperature.This illustrates that pressure and temperature are directly proportional.

Accepted Answer

The statement is correct. According to Gay-Lussac's law, the pressure of a gas is directly proportional to its temperature when the volume is constant. If the temperature of the gas inside an aerosol spray can increases due to external heat, the pressure inside the can will also increase and may lead to an explosion.

Question 16

Charles's Law provides an explanation of why hot air balloons float.

Accepted Answer

Charles's Law states that at a constant pressure, the volume of a gas increases as its temperature increases. This means that as the air inside a hot air balloon is heated, it expands and becomes less dense than the surrounding air, causing the balloon to rise and float.

Question 17

Absolute zero refers to 0°C.

Accepted Answer

Absolute zero refers to the temperature -273.15°C or 0 Kelvin, which is the lowest possible temperature at which all substances have zero thermal energy.

Question 18

A gas may not behave ideally under conditions of low pressure or high temperature.

Accepted Answer

A gas is more likely to behave ideally under conditions of low pressure and high temperature, as these conditions allow the gas particles to move more freely and independently, reducing the effects of intermolecular forces.

Question 19

If some argon gas at 400 mm Hg pressure is forced into a gas cylinder that already contained only neon gas at 400 mm Hg pressure,the total pressure in the cylinder would now be 800 mm Hg.

Accepted Answer

According to Dalton's law of partial pressures, the total pressure exerted by a mixture of gases is equal to the sum of the pressures exerted by each gas alone. Therefore, if argon gas is added to a gas cylinder containing only neon gas at the same pressure, the total pressure in the cylinder would be the sum of the pressures exerted by each gas, which is 400 mm Hg + 400 mm Hg = 800 mm Hg.

Question 20

The main component of the air we breathe is oxygen gas.

Accepted Answer

The main component of the air we breathe is nitrogen gas, which makes up about 78% of the air. Oxygen gas only makes up about 21%.

Quiz 11: Gases