1.
A sample of gas is collected by water displacement. The atmospheric pressure in the room is 757 mm Hg and the vapor pressure of water is 17 mm Hg. What is the partial pressure of hydrogen under these conditions?
Correct Answer
B. 740 mm Hg
Explanation
The partial pressure of hydrogen under these conditions is 740 mm Hg because the vapor pressure of water (17 mm Hg) needs to be subtracted from the atmospheric pressure in the room (757 mm Hg) to determine the partial pressure of the gas collected.
2.
At constant temperature, if a gas occupies 312 mL at a
pressure of 1.60 atm, what pressure is necessary for this
gas to occupy a volume of 500 mL
Correct Answer
A. 1.00 atm
Explanation
At constant temperature, the relationship between the pressure and volume of a gas is described by Boyle's Law. Boyle's Law states that the product of the initial pressure and volume is equal to the product of the final pressure and volume. In this case, the initial pressure is 1.60 atm and the initial volume is 312 mL. The final volume is given as 500 mL. By rearranging the equation, we can solve for the final pressure. Plugging in the values, we find that the final pressure is 1.00 atm.
3.
Boyle's Law shows?
Correct Answer
A. The inverse relationship between the volume and pressure of a gas
Explanation
Boyle's Law states that there is an inverse relationship between the volume and pressure of a gas, meaning that as the volume of a gas decreases, the pressure increases, and vice versa. This relationship was discovered by Robert Boyle in the 17th century and is one of the fundamental principles in the study of gases.
4.
A gas of volume 5 m^{3} and 1x10^{5} Pa is compressed until its volume is 2 m^{3} . What is the new pressure of the gas?
Correct Answer
B. 2.5x105 Pa
Explanation
The gas is being compressed, which means its volume is decreasing. According to Boyle's Law, when the volume of a gas decreases, its pressure increases, as long as the temperature remains constant. In this case, the volume is decreasing from 5 m^3 to 2 m^3, so the pressure will increase. Since the initial pressure is 1x10^5 Pa, and the volume is decreasing by a factor of 2.5 (5/2), the new pressure will increase by the same factor. Therefore, the new pressure of the gas will be 2.5x10^5 Pa.
5.
A sample of gas is heated in a sealed container from 27°C
to 127°C. The volume of gas stays constant. What is the final pressure of the gas if the initial pressure is 1.2x10^{5}
Pa?
Correct Answer
B. 1.6x105 Pa
Explanation
When a sample of gas is heated in a sealed container with constant volume, according to Charles's Law, the pressure of the gas is directly proportional to its temperature. As the temperature increases from 27°C to 127°C, the pressure of the gas also increases. Therefore, the final pressure of the gas will be higher than the initial pressure of 1.2x105 Pa. Among the given options, the only value that is higher than 1.2x105 Pa is 1.6x105 Pa, so that is the correct answer.
6.
Boyle's Law: P1V1=P2V2 The volume of a gas at 99.0 kPa is 300mL. If the pressure increases to 188kPa, what is the final volume?
Correct Answer
C. 158mL
Explanation
According to Boyle's Law, the product of the initial pressure and volume is equal to the product of the final pressure and volume. In this question, the initial pressure is given as 99.0 kPa and the initial volume is given as 300 mL. The final pressure is given as 188 kPa. To find the final volume, we can rearrange the equation as V2 = (P1V1) / P2. Plugging in the given values, we get V2 = (99.0 kPa * 300 mL) / 188 kPa. Solving this equation gives us the final volume of 158 mL.
7.
Charles' Law: V1/T1 = V2/T2 The celsius temperature of a 3.00L sample of gas is lowered from 80.0 C to 30.0 C. What is the final volume?
Correct Answer
C. 2.58L
Explanation
According to Charles' Law, the volume of a gas is directly proportional to its temperature in Kelvin. In this question, the temperature of the gas is lowered from 80.0°C to 30.0°C. To use Charles' Law, we need to convert these temperatures to Kelvin by adding 273.15 to each. So, the initial temperature is 353.15K and the final temperature is 303.15K. Using the formula V1/T1 = V2/T2, we can plug in the values to find the final volume. V1 is given as 3.00L and T1 is 353.15K. T2 is 303.15K and we need to solve for V2. Rearranging the formula, we get V2 = (V1 * T2) / T1. Plugging in the values, we get V2 = (3.00 * 303.15) / 353.15 = 2.58L.
8.
Using Avogadro’s Principle, identify which of the following conditions is correct?
Correct Answer
A. At the same temperature and same pressure, 1 mole of two different gases occupies the same volume
Explanation
According to Avogadro's Principle, at the same temperature and pressure, 1 mole of two different gases will occupy the same volume. This principle states that equal volumes of gases, at the same temperature and pressure, contain an equal number of molecules. Therefore, since 1 mole of any gas contains the same number of molecules, it will occupy the same volume as 1 mole of any other gas under the same conditions.
9.
Id eal g ases
Correct Answer
D. Combination of choices a and c
Explanation
Ideal gases have no volume because they are assumed to occupy no space and have no mass. Additionally, ideal gases have no attractive forces between them, as they are considered to have perfectly elastic collisions and no intermolecular forces. Therefore, the correct answer is a combination of choices a and c, indicating that ideal gases have no volume and no attractive forces between them.
10.
At a temperature of 440. K, a gas exerts a pressure of 240. kPa. If the pressure is lowered to 60. kPa, what is the temperature of the gas? For this question, do NOT place units on response
Correct Answer
110
110.
11.
As the temperature of cloud of gasoline vapor is warmed by the sun, what happens to the volume of the cloud?
Correct Answer
A. The cloud's volume increases as the temperature of a gas is directly related to its volume.
Explanation
When the temperature of a gas increases, its volume also increases. This is known as Charles's Law, which states that the volume of a gas is directly proportional to its temperature, assuming that pressure and amount of gas remain constant. Therefore, as the temperature of the cloud of gasoline vapor is warmed by the sun, its volume will increase.
12.
A gas that occupies 44 L exerts a pressure of 25 kPA. If the volume of the container shrinks to 22 L, what is the new gas pressure? For this question, do NOT place units on entered response.
Correct Answer
50
50.
fifty
13.
For a confined gas kept at constant temperature, what relationship exists between the pressure exerted by the gas and the volume the gas occupies?
Correct Answer
C. These variables are inversely related because increasing volume of the gas decreases the pressure the gas exerts
Explanation
The relationship between the pressure exerted by a confined gas and the volume it occupies is inversely related. This means that as the volume of the gas increases, the pressure it exerts decreases. This is because when the volume of the gas increases, the gas particles have more space to move around and collide with each other and the container walls less frequently, resulting in a decrease in the pressure exerted by the gas.
14.
At a temperature of 444 K a gas occupies a volume of 480. L. If the volume of the gas is reduced to 240. L, what temperature is required? For this question, do NOT place units on response
Correct Answer
222
Explanation
According to Charles's Law, the volume of a gas is directly proportional to its temperature at constant pressure. Therefore, if the volume of the gas is halved from 480 L to 240 L, the temperature must also be halved from 444 K to 222 K in order to maintain the same proportionality.
15.
A temperature of 200. K, a gas exerts a pressure of 32 atm. If the temperature rises to 600. K, what will be the new pressure exerted by the gas? For this question, do NOT place units on response.
Correct Answer
96
16.
A balloon is inflated to a volume of 130 ml at a pressure of 690 mmHg. If the pressure is increased to 1000 mmHg, what will the new volume be?
Correct Answer
C. 89.7 ml
Explanation
When the pressure of a gas increases, the volume decreases, and vice versa, according to Boyle's Law. In this question, the initial volume of the balloon is 130 ml at a pressure of 690 mmHg. When the pressure is increased to 1000 mmHg, the new volume can be calculated using Boyle's Law formula: P1V1 = P2V2. Plugging in the given values, we get (690 mmHg)(130 ml) = (1000 mmHg)(V2). Solving for V2, we find that the new volume is 89.7 ml.
17.
Carbon dioxide occupies a 2.54 L container at STP. What will be the volume when the pressure is 150 KPa and 26 C?
Correct Answer
A. 1.89 L
Explanation
At STP (Standard Temperature and Pressure), the volume of a gas is directly proportional to the temperature and inversely proportional to the pressure. In this question, the pressure and temperature are given as 150 KPa and 26°C respectively. To find the new volume, we can use the equation: (V1/T1) = (V2/T2) * (P2/P1), where V1 is the initial volume, T1 is the initial temperature, V2 is the final volume, T2 is the final temperature, P1 is the initial pressure, and P2 is the final pressure. Plugging in the values, we get: (2.54/273) = (V2/299) * (150/101.3). Solving for V2, we find V2 = 1.89 L.
18.
The volume of a gas is increased from 150.0 mL to 350.0 mL by heating it. If theoriginal temperature of the gas was 25.0 °C?
Correct Answer
C. 695 C
Explanation
When a gas is heated, its volume increases. In this case, the volume of the gas is increased from 150.0 mL to 350.0 mL. Therefore, the temperature of the gas must have increased significantly. The increase in temperature is given as 695 °C.