Pressure and Temperature

Q. A tube of length 1 m is completely filled with mercury and is inverted in a mercury cup for constructing a barometer which reads 76 cm. Suppose a 1 m tube is filled with mercury upto 76 cm and closed by the cork.
It is inverted into a tray containing mercury and the cork is opened. The height of mercury column now in the tube over the surface of mercury in the tray will be:

1. 76 cm
2. Zero
3. >76 cm
4. <76 cm

Q. A gas is confined in a chamber of constant volume. When the chamber is immersed in a bath of melting ice, the pressure of the gas is 1000 torr. The final temperature, when the pressure in the manometer indicates an absolute pressure of 400 torr is:

1. $109\text{K}$
2. $273\text{K}$
3. $373\text{K}$
4. $0\text{K}$

Q.

Why solids are rigid?

Q. In the given figure, the height of a mercury barometer is 'h' cm when the atmospheric pressure is 101, 000 Pa. Find the pressure at point X.

1. 134.67 kPa
2. 156.37 kPa
3. 143.32 kPa
4. 75.75 kPa

Q. The height of water $\rho =1000kg/m^3$ and oil $\rho =720kg/m^3$ are 6 m and 5m inside an open barometer. What is the atmospheric pressure in kPa?

1. 136.42 kPa
2. 65.98 kPa
3. 101.25 kPa
4. 91.34 kPa

Q. If the mercury in the barometer is replaced by water, What will be the resulting height of the water column?
Given: Density of water = $1000kg{m}^3$, Density of mercury = $13600kg{m}^3$

1. $0.76m$
2. $10.3m$
3. $11.2m$
4. $9.8m$

Q. An ideal gas undergoes adiabatic expansion against external pressure. Which of the following are correct ?

1. Internal energy of the gas remains unchanged
2. Internal energy of the gas decrease
3. Temperature of the system decreases
4. $\Delta E+P\Delta V=0$

Q.

Solids have the smallest inter-molecular space and the strongest inter-molecular force of attraction among its molecules.

1. True
2. False

Q. Which of the following graph is correct for the given two step endothermic reaction?

दी गयी दो पदीय ऊष्माशोषी अभिक्रिया के लिए निम्नलिखित में से कौनसा ग्राफ सही है?

1. 
2. 
3. 
4. 

Q.

Why solids are hard and rigid?

Q. When a bubble containing ideal gas rises from the bottom of a lake to the surface, its radius doubles. If atmospheric pressure is equal to that of a column of water height H, then the depth of lake is:

1. H
2. 2H
3. 7H
4. 8H

Q.

Which of the following statement is correct about solids?

1. They are less rigid.

2. They show maximum expansion on heating.

3. They have large intermolecular distance between the molecules.

4. They have the strongest intermolecular force of attraction between the molecules.

Q.

Why can the molecules of solids not interchange their positions?

Q. Which of the following statement(s) are correct regarding gaseous state of matter?

1. Complete order of molecules
2. Complete diorder of molecules
3. Random motion of molecules
4. Fixed position of molecules

Q.

The critical temperature of ${\mathrm{CO}}_2$ gas and the${\mathrm{N}}_2$gas are 31^oC and -147⁰C, respectively. Which gas is liquefied easily and why?

Q. A closed tank has two compartments A and B, both filled with oxygen (assumed to be ideal gas). The partition separating the two compartments is fixed and is a perfect heat insulator (Figure 1). If the old partition is replaced by a new partition which can slide and conduct heat but does not allow the gas to leak across (Figure 2), the volume (in $m^3)$ of the compartment A after the system attains equilibrium is.

Q. Height of a mercury column is given as 76 cm of Hg in a barometer. Find the height of the column of a liquid of density 1.2 g/cc would be neccessary to balance atmospheric pressure
Given: Density of mercury = 13600 kg/$m^3$

1. 546.8 cm
2. 742.6 cm
3. 432.5 cm
4. 861.3 cm

Q. The heat transferred in the process.

Q.

Identify the wrong statement among the following.

1. In solids, molecules are closely packed.

2. In solids, molecules have very strong intermolecular forces of attraction.

3. In solids, molecules have only vibratory motion about their mean positions.

4. In solids, molecules possess very high kinetic energy

Q. 51. Explain Lewis representation of molecules

Q. The ratio of height of a mercury column in a barometer at a place to the height of the liquid column at the same place are 1:4. Find the density of the liquid in g/$c{m}^3$.

1. 10.5 g/$c{m}^3$
2. 4.8 g/$c{m}^3$
3. 3.4 g/$c{m}^3$
4. 5.6 g/$c{m}^3$

Q. A balloon having a volume of $4200{\text{m}}^3$ is filled with a gas at ${27}^{\circ }\text{C},and1$ bar pressure. It weighs $700\text{kg}$. If the density of air is $1.2{\text{kg m}}^{-3}$, then the pay load of the balloon is:

1. $5040\text{kg}$
2. $4340\text{kg}$
3. $3500\text{kg}$
4. $5740\text{kg}$

Q.
Two spheres - 1, 2 with flexible walls are connected by a tube of negligible volume. Their initial and final conditions are given by $P_1,V_1,n_1$ and $P_2,V_2,n_2$ respectively. The radius of these spheres depends on the temperature as $4\pi r^{2}dr=kdT$. Initially, sphere 1 was at $100K$ and sphere 2 was at $200K$. As the temperature of sphere 1 is increased to $300K$, find the final mole ratio $\left(\frac{n_1^{\prime }}{n_2^{\prime }}\right)$.

Q. A gas cylinder containing cooking gas can withstand a pressure 14.9 atmosphere. The pressure guage of the cylinder indicates 12 atmosphere at ${27}^{\circ }\text{C}$. Due to a sudden fire in the building, the temperature starts rising. Find the temperature ( K) when the cylinder explodes?