1. | \(223\) \(\text{K}\) | 2. | \(669^\circ \mathrm{C}\) |
3. | \(3295^\circ \mathrm{C}\) | 4. | \(3097\) \(\text{K}\) |
1. | all vessels contain unequal number of respective molecules. |
2. | the root mean square speed of molecules is same in all the three cases. |
3. | the root mean square speed of helium is the largest. |
4. | the root mean square speed of sulfur hexafluoride is the largest. |
The temperature at which the rms speed of atoms in neon gas is equal to the rms speed of hydrogen molecules at \(15^{\circ} \mathrm{C}\) is: (Atomic mass of neon\(=20.2\) u, molecular mass of hydrogen\(=2\) u)
1. \(2.9\times10^{3}\) K
2. \(2.9\) K
3. \(0.15\times10^{3}\) K
4. \(0.29\times10^{3}\) K
Match Column - I and Column - II and choose the correct match from the given choices.
Column - I | Column - II | ||
(A) | root mean square speed of gas molecules | (P) | \(\frac13nm\bar v^2\) |
(B) | the pressure exerted by an ideal gas | (Q) | \( \sqrt{\frac{3 R T}{M}} \) |
(C) | the average kinetic energy of a molecule | (R) | \( \frac{5}{2} R T \) |
(D) | the total internal energy of 1 mole of a diatomic gas | (S) | \(\frac32k_BT\) |
(A) | (B) | (C) | (D) | |
1. | (Q) | (P) | (S) | (R) |
2. | (R) | (Q) | (P) | (S) |
3. | (R) | (P) | (S) | (Q) |
4. | (Q) | (R) | (S) | (P) |
The diameter of the water vapour molecule is and the number of molecules per unit volume at STP is The mean free path for a water molecule in water vapour at \(373\) \(\mathrm{K}\) is:
1.
2.
3.
4.
A cylinder of fixed capacity \(44.8\) litres contains helium gas at standard temperature and pressure. What is the amount of heat needed to raise the temperature of the gas in the cylinder by \(15.0^\circ~\mathrm{C}?\) (\(R=8.31\) J mol–1 K–1)
1. | \(379\) J | 2. | \(357\) J |
3. | \(457\) J | 4. | \(374\) J |
When a molecule (or an elastic ball) hits a ( massive) wall, it rebounds with the same speed. When a ball hits a massive bat held firmly, the same thing happens. However, when the bat is moving towards the ball, the ball rebounds at a different speed. Does the ball move faster or slower?
1. | faster |
2. | slower |
3. | The speed of the ball does not change |
4. | none of these |
Uranium has two isotopes of masses 235 and 238 units. If both are present in Uranium hexafluoride gas. If the atomic mass of fluorine is 19 units, what is the percentage difference in speeds of isotopes of Uranium at any temperature?
1. 0.43%
2. 0.34%
3. 0.55%
4. Data insufficient