At which condition, van der Waals real gas act as an ideal gas ?
High temperature, low pressure
Low temperature, high pressure
High temperature, high pressure
Low temperature, low pressure
The first order diffraction of X-rays from a certain set of crystal planes occur at an angle of 11.8º from the planes. If the planes are 0.281 nm apart, what is the wavelength of X-rays?
0.281 nm
0.2044 nm
0.1149 nm
0.1180 nm
Which is not true in case of ideal gas?
It can not be converted into a liquid
There is no interaction between the molecules
All molecules of the gas move with same speed
At a given temperature, PV is proportional to the amount of gas.
Which of the following expressions is correct for a CsCl unit cell with lattice parameter, a?
If 10-4 dm3 of water is introduced into a 1.0 dm3 flask at 300 K, how many moles of water are in the vapour phase when equilibrium is established?
[ Given, vapour pressure of H2O at 300 K is 3170 Pa; R = 8.314 JK-1 mol-1 ]
5.56 x 10-3 mol
1.53 x 10-2 mol
4.46 x 10-2 mol
1.27 x 10-3 mol
For a mono atomic gas kinetic energy = B. The relation with rms velocity is
For an ideal gas, number of moles per litre in terms of its pressure P, temperature T and gas constant R is
PRT
A balloon blown up with 1 mole of gas has a volume of 480 mL at 5ºC. The balloon is filled to 7/8th of its maximum capacity. Will the balloon burst at 30ºC?
Balloon will burst
Balloon will not burst
Bursting of balloon is independent of temperature
Cannot be predicted
Why beans were cooked earlier in pressure cooker ?
b.p increases with increasing pressure.
b.p decreases with increasing pressure.
extra pressure of pressure cooker, softens the beans.
internal energy is not lost while cooking in pressure cooker.
A mixture of NH3(g) and N2H4(g) is placed in a sealed container at 300K. The total pressure is 0.5 atm. When the container is heated to 1200 K, both substances decompose completely according to the equations :
2NH3 (g) → N2(g) + 3H2(g)
and N2H4(g) → N2(g) + 2H2(g)
After decomposition, the total pressure at 1200 K is found to be 4.5 atm. What is the percent of N2H4(g) in the original mixture? (assuming ideal behaviour)
35%
40%
75%
25%
