# Root Mean Square Velocity

## Trending Questions

**Q.**The root mean square speed of molecules of nitrogen gas is v at a certain temperature. When the temperature is doubled, the molecules dissociate into individual atoms. The new rms speed of the atom is:

- √2v
- 2v
- v
- 4v

**Q.**The molar mass of a certain gas B is double than that of A. Also the RMS velocity of gas A is 200 ms−1 at a certain temperature. RMS velocity of gas B at the temperature half of the temperature of A is:

- 200 ms−1
- 300 ms−1
- 400 ms−1
- 100 ms−1

**Q.**In a container of capacity 1 litre there are 1023 molecules each of mass 10−22 g. If the root mean square speed is 105 cm/s then, calculate the pressure of the gas.

- 1 atm
- 1 torr
- 13×107 Pa
- 1×107 Pa

**Q.**A vessel of capactity 1 dm3 contains 1.03×1023 H2 molecules exerting a pressure of 101.325 kPa. Calculate RMS speed and average speed.

- RMS speedAverage speed942.5 m s−1868.35 m s−1
- RMS speedAverage speed942.5 m s−1722.12 m s−1
- RMS speedAverage speed942.5 m s−1622.53 m s−1
- RMS speedAverage speed868.36 m s−1942.5 m s−1

**Q.**The average velocity of gas molecules is 400 m/sec. Calculate its rms velocity at the same temperature.

**Q.**The density of a gas filled in an electric lamp is 0.75 kg/m3 . After the lamp has been switched on, the pressure in it increases from 4×104 Pa to 9×104 Pa. What is the increase in URMS ?

- 100 m/s
- 200 m/s
- 300 m/s
- None of these

**Q.**A flask has 10 gas particles out of which four particles are moving at 7 ms−1 and all the remaining ones are moving at the speed of 'x' ms−1. If the Vrms of the gas is 5 ms−1, what is the value of ‘x′ ?

**Q.**At what temperature will the r.m.s velocity of oxygen be 3/2 times of its value at S.T.P.?

- 614.25 K
- 674.25 K
- 914.25 K
- 974 K

**Q.**Temperature at which the rms speed of O2 is equal to that of neon at 300 K is:

- 280 K
- 680 K
- 180 K
- 480 K

**Q.**The root mean square velocity of hydrogen is √5 times than that of nitrogen. If T is the temperature of the gas, then:

- TH2=TN2
- TH2>TN2
- TH2<TN2
- TH2=√7TN2

**Q.**The root mean square speed of 8 g of He is 300 ms−1. Total kinetic energy of He gas is:

- 120 J
- 240 J
- 360 J
- None of these

**Q.**For CO2, given that average velocity at T1 is equal to most probable velocity at T2. Thus, T1T2

- 1.27
- 0.78
- 1.13
- 2.26

**Q.**A gas 1g at 4 bar pressure. If we add 2g of gas B then the total pressure inside the container is 6 bar. Which of the following is true ?

- MA=2MB
- MB=2MA
- MA=4MB
- MB=4MA

**Q.**Temperature at which the rms speed of O2 is equal to that of neon at 300 K is:

- 280 K
- 480 K
- 680 K
- 180 K

**Q.**In a container of capacity 1 litre, there are 1023 molecules each of mass 10−22 g. If the root mean square speed is 105 cm/s then calculate the pressure of the gas.

- 13×107 Pa
- 1×107 Pa
- 1 atm
- 1 torr

**Q.**At 298 K, which of the following gases has the lowest average molecular speed ?

- CH4 at 0.80 atm
- He at 0.40 atm
- CO2 at 0.20 atm
- NO at 1.00 atm

**Q.**For CO2, given that average velocity at T1 is equal to most probable velocity at T2. Thus, T1T2

- 2.26
- 1.27
- 0.78
- 1.13

**Q.**Two containers are maintained at the same temperature. The first one has a volume of 8 litres and stores hydrogen at 2 atm. The other one has a volume of 4 litres and stores oxygen at 1 atm. What is the ratio of the root mean square velocities of hydrogen and oxygen?

- 4:1
- 1:4
- 1:16
- 16:1

**Q.**Distribution of fraction of molecules with velocity is represented in the figure.

Velocity corresponding to point X is:

- √2RTM
- √3RTM
- √8RTM
- None

**Q.**A vessel of capactity 1 dm3 contains 1.03×1023 H2 molecules exerting a pressure of 101.325 kPa. Calculate RMS speed and average speed.

- RMS speedAverage speed942.5 m s−1868.35 m s−1
- RMS speedAverage speed942.5 m s−1722.12 m s−1
- RMS speedAverage speed868.36 m s−1942.5 m s−1
- RMS speedAverage speed942.5 m s−1622.53 m s−1

**Q.**Identify the correct statement(s).

- For a gas in a rigid container, mean free path is independent of pressure and temperature
- Translational kinetic energy of a given amount of an ideal gas is independent of pressure
- All the molecules of a gas at a given temperature have the same kinetic energy
- The average kinetic energy of 1 mol of gas molecules at a given temperature is proportional to ′M′. (where 'M' is molar mass of gas)

**Q.**The kinetic energy of a molecule of a gas is directly proportional to the _______ of the gas.

- pressure of the gas
- absolute temperature
- mass of the gas
- none of these

**Q.**At same temperature, calculate the ratio of average velocities of SO2 and CH4:

- 2 : 3
- 3 : 4
- 1 : 2
- 1 : 6

**Q.**For gaseous state, if the most probable speed is denoted by C∗, average speed by ¯C and root mean square speed by C, then for a large number of molecules, the ratios of these speeds are:

- C∗¯CC1.2251.1281
- C∗¯CC11.1281.225
- C∗¯CC1.1281.2251
- C∗¯CC11.1251.128

**Q.**The molar mass of a certain gas B is double than that of A. Also the RMS velocity of gas A is 200 ms−1 at a certain temperature. RMS velocity of gas B at the temperature half of the temperature of A is:

- 200 ms−1
- 300 ms−1
- 400 ms−1
- 100 ms−1

**Q.**The ratio of the root mean square speed of H2 gas at 50 K and that of O2 gas at 800 K is:

- 4
- 2
- 1
- 0.25

**Q.**Which of the following gaseous fuels has the lowest calorific value?

- Refinery gas
- Gober gas
- Converter gas
- Blast furnace gas

**Q.**In a container of capacity 1 litre, there are 1023 molecules each of mass 10−22 g. If the root mean square speed is 105 cm/s then calculate the pressure of the gas.

- 13×107 Pa
- 1×107 Pa
- 1 atm
- 1 torr

**Q.**For CO2, given that average velocity at T1 is equal to most probable velocity at T2. Thus, T1T2

- 2.26
- 1.27
- 0.78
- 1.13

**Q.**For gaseous state, most probable speed is denoted by C∗, average speed by ¯C and root mean square speed by C respectively. For the same number of molecules at same temperature, the ratios of these speeds are:

- C∗:¯C:C=1.225:1.128:1
- C∗:¯C:C=1.128:1.225:1
- C∗:¯C:C=1:1.128:1.225
- C∗:¯C:C=1:1.225:1.128