Gas Laws: Pressure, Temperature, Volume & Gas Laws: Ideal Gas Laws

Which of the following correctly represents the standard conditions for temperature and pressure (STP)?

zero degrees Celsius and one atmosphere Zero degrees Celsius and one atmosphere of pressure constitute standard conditions of temperature and pressure.

Which plot will give a straight line?

V vs. 1P Volume and pressure are inversely related, so only the reciprocal of the pressure against volume results in a linear plot.

Charles's law is described by which of the following equations?

V=kT VT=k V1T1=V2T2

If the pressure of a gas is kept constant and the temperature (in Kelvin) is cut in half, the volume will __________.

be cut in half Since they are directly proportional, if one is cut in half, the other must also be halved.

For an ideal gas, volume and temperature are __________ proportional.

directly For an ideal gas, volume and temperature are directly proportional. Charles's law states that the volume of a given amount of gas is directly proportional to its temperature on the Kelvin scale when pressure is constant. This can be seen in V1T1=V2T2. If the temperature of a gas was to increase, the volume would increase. If the temperature of a gas was to decrease, the volume would decrease.

Which is a correct way of stating Amontons's (Gay-Lussac's) law?

P=kT PT=k P1T1=P2T2

What is true for ideal gases at STP conditions? Select all that apply.

The standard molar volume is 22.4L. One mole of any ideal gas has the same volume. Chemists sometimes make comparisons against a standard temperature and pressure (STP) for reporting properties of gases. At STP, one mole of an ideal gas has a volume of 22.4L. This is referred to as the standard molar volume.

Assuming the temperature and the amount of gas are held constant, a plot of volume vs. pressure will give a:

hyperbola If we plot pressure versus volume, we obtain a hyperbola. This is because pressure and volume exhibit inverse proportionality; increasing the pressure results in a decrease of the volume of the gas. Mathematically, this can be written as follows: PP∝1V=kV Therefore, a plot of pressure vs volume will have the same shape as the function f(x)=1x.

Which is a correct way of stating Boyle's law?

P=k×1V, where k is a constant. PV=k, where k is a constant. P1V1=P2V2, where the indices 1 and 2 corresponds to different states of the same gas sample.

Pressure and volume of an ideal gas are __________.

inversely proportional As volume decreases, the pressure will increase if temperature is kept constant, according to Boyle's law.

Which variable is NOT present in the ideal gas law?

mass The equation for the ideal gas law is as follows: PV=nRT Mass is not represented in this equation. The n represents moles not mass.

Gay-Lussac's law assumes that __________.

the volume is held constant the number of moles is held constant According to Gay-Lussac's law, the pressure and temperature of a gas (in degrees Kelvin) are directly proportional. If one increases, the other one will increase as well (and the same for decrease). This relationship is valid as long as the volume and number of moles of gas are held constant.

Under what condition does the volume of the ideal gas approach zero?

when the temperature approaches 0 From the ideal gas law PV=nRT we can derive the relationship between the volume and temperature (at constant pressure and number of moles) as follows:V=T×constantTherefore, if temperature equals zero kelvin, the volume is zero.

Which of the following represents STP? Select all that apply.

1atm and 273.15K 101.325kPa and 273.15K 1atm and 0∘C 101.325kPa and 0∘C Standard pressure is defined as 1atm or 101.325kPa. Standard temperature is defined as 273.15K or 0∘C.

Which of the following states that the pressure of a given amount of gas is directly proportional to its temperature on the Kelvin scale when the volume is held constant?

Amontons's or Gay-Lussac's law Amontons's or Gay-Lussac's law states that the pressure of a given amount of gas is directly proportional to its temperature on the Kelvin scale when the volume is held constant. This can be seen in P1T1=P2T2. As the temperature of a gas increases by a certain factor, the gas pressure will also increase by the same factor. And if the temperature of a gas decreases by a certain factor, the gas pressure will also decrease by the same factor.

Why is it important to know gas properties at STP?

Because comparison of properties is possible only if the properties are reported against a standard temperature and pressure. In order to know that exactly one mole of an ideal gas has a volume of 22.4L. Chemists sometimes make comparisons against a standard temperature and pressure (STP) for reporting properties of gases. At STP, one mole of an ideal gas has a volume of 22.4L. This is referred to as the standard molar volume.

Identify which of the following statements is true about ideal gas behavior in a closed container.

If the temperature increases while the volume remains the same, the pressure also increases. Since the number of moles (n) in a closed container is constant, the product nR is constant, and the ideal gas law can be rewritten as follows. PVPVT=nRT=nR Since the right side of the equation is constant, the left side is as well, and the relationship between changes in P, V, and T can be determined. Of the choices given, only increasing the temperature and pressure can maintain a constant value of PVT.

Which of the following best explains why gases deviate from ideal behavior at high density?

The ideal gas law assumes that the gas molecules do not interact. At higher densities, the molecules are closer on average and may experience attractive or repulsive forces that cause the behavior to deviate from ideal. The ideal gas law assumes that the gas molecules do not interact. At higher densities, there are more molecules in the same volume, which means they are closer on average. Attractive and repulsive forces between molecules decrease to zero as the distance between molecules increases, so the assumption is more applicable at low densities. At higher densities, the molecules may experience attractive or repulsive forces that cause the behavior to deviate from ideal.

Under which set of conditions do real gases deviate the most from the ideal gas law?

low temperature and high pressure Real gases deviate from ideal behavior under low temperature and high pressure. The ideal gas law assumes that no interactions occur between gas molecules. At high pressure, molecules are crowded together, and they interact with each other (repulsive forces). Similarly, at low temperatures, the gas molecules have low kinetic energy and become more sensitive to attractive forces between molecules.