Molar and Specific Heat Capacity

Q.

What is the specific heat of ice in calories?

Q. Equal volumes of two monoatomic gases, A and B at same temperature and pressure are mixed. The ratio of specific heats $\frac{C_p}{C_v}$ of the mixture will be:

1. 0.83
2. 1.5
3. 3.3
4. 1.67

Q.

Calculate the number of kJ of heat necessary to raise the temperature of 60.0 g of aluminium from ${35}^{\circ }C$ to ${55}^{\circ }C$. Molar heat capacity of Al is $24Jmo{l}^{-1}{K}^{-1}$

Q.

When $1$ mole of gas is heated at constant volume, the temperature is raised from $298$ to $308K$ and heat supplied to gas is $500J$. Which of the following statements is true?

1. $\mathrm{q}=\mathrm{W}=500\mathrm{J}$, $∆\mathrm{U}=0$

2. $\mathrm{q}=\mathrm{W}=-500\mathrm{J}$, $∆\mathrm{U}=0$

3. $\mathrm{q}=∆\mathrm{U}=500\mathrm{J}$, $\mathrm{W}=0$

4. $\mathrm{q}=-\mathrm{W}=500\mathrm{J}$, $∆\mathrm{U}=0$

Q. A gas expands from a volume of 3.0 $d{m}^3$ to 5 $d{m}^3$ against a constant pressure of 3.0 atm. The work done during expansion is used to heat 10.0 mole of water of temperature 290.0 K. Calculate the final temperature of water. (Specific heat of water = 4.184 $J{K}^{-1}{g}^{-1}$

1. 304.526 K
2. 275.470 K
3. 289.193 K
4. 290.807 K

Q. A diatomic ideal gas initially at $273K$ is given $100cal$ heat due to which system did $209J$ work. Molar heat capacity $\left(C_m\right)$ of gas for the process is:

1. $\frac{5}{4}R$
2. $5R$
3. $\frac{3}{2}R$
4. $\frac{5}{2}R$

Q. The molar heat capacity $C_m$ of an ideal gas:

1. must be equal to $C_p$ or $C_v$
2. Cannot be negative
3. must have any value between $0$ to $+\infty$
4. must lie in the range $C_v<C<C_p$

Q.

For the hypothetical reaction $A_2\left(g\right)+B_2\left(g\right)\rightleftharpoons 2AB\left(g\right){\Delta }_r{G}^{\circ }$ and ${\Delta }_r{S}^{\circ }$ are $20kJ/mol$ and $-20J{K}^{-1}mo{l}^{-1}$ respectively at $200K$. If ${\Delta }_r{C}^p$ is $20J{K}^{-1}mo{l}^{-1}$ then ${\Delta }_r{H}^{\circ }$ at $400K$ is

1. 20 kJ/mol

2. 7.98 kJ/mol

3. 28 kJ/mol

4. None of these

Q. The dimensional formula for molar thermal capacity is same that of- (i)gas constant (ii)stefans constant (iii)Boltzmann constant (iv)specific heat give brief explanation

Q. Consider a system containing one mole of a diatomic gas, contained by a piston. What is the temperature change of the gas, if $q=50J$ and $W=-100J?$
(Given $C_v=\frac{5}{2}R$ )

1. $-1.25K$
2. $-50K$
3. $-2.4K$
4. $-5.8K$

Q. At $298\text{K}$, one mole of which of the following gases has the lowest average molecular speed?

1. $C{H}_4\text{at}0.80\text{atm}$
2. $C{O}_2\text{at}0.20\text{atm}$
3. $NO\text{at}1.00\text{atm}$
4. $He\text{at}0.40\text{atm}$

Q. Ice-water mass ratio is maintained as 1 : 1 in a given system containing water in equilibrium with ice at constant pressure. If $C_P\left(ice\right)=C_P\left(water\right)=4.18Jmo{l}^{-1}{K}^{-1}$ molar heat capacity of such a system is

1. Zero
2. Infinity
3. $4.182J{K}^{-1}mo{l}^{-1}$
4. $75.48J{K}^{-1}mo{l}^{-1}$

Q.

For an ideal gas $(\frac{C_P}{C_v}=\gamma )$; of molar mass M, its specific heat capacity at constant volume is:

1. 

2. 

3. 

4. 

Q. A gas expands from a volume of $3.0d{m}^3$ to $5.0d{m}^3$ against a constant pressure of $3.0atm$ the work done during expansion is used to heat $10.0$ mole of water of temperature $290.0K$ Calculate the final temperature of water (specific heat of water $=4.184J{K}^{-1}{g}^{-1}$)

1. $290K$
2. $289.2K$
3. $290.8K$
4. $291.8K$

Q. The compressibility factor for a real gas at high pressure is:

1. $1+\frac{RT}{Pb}$
2. $1+\frac{Pb}{RT}$
3. $1-\frac{Pb}{RT}$
4. 1

Q.

If specific heat capacity of mercury is $0.033cal{g}^{-1}{}^{0}C^{-1}$, how much heat is gained by $0.05kg$ of mercury when its temperature rises from ${68}^{0}F$ to $313K$?

Q.

The calorific value of methane in the following reaction is about-

$2C{H}_4+4O_2\to 2C{O}_2+4H_{2}O+1780kJ$

1. $55kJ/g$

2. $110kJ/g$

3. $110J/g$

4. $55J/g$

Q.

Assertion: Specific heat capacity of a substance is a constant quantity.

Reason: It is the amount of heat energy required to raise the temperature of 1 g of a substance by 1 °C. As with the mass, the temperature and the nature of the substance do not change. So, it is a constant quantity.

1. Both ‘A’ and ‘R’ are correct and ‘R’ is the correct explanation of ‘A’.

2. Both ‘A’ and ‘R’ are correct, but ‘R’ is not the correct explanation of ‘A’.

3. ‘A’ is correct, but ‘R’ is incorrect

4. ‘A’ is incorrect, but ‘R’ is correct

Q. The molar heat capacity ( $C_p$) of water at constant pressure is 75 $J{K}^{-1}mol{e}^{-1}$. The increase in temperature (in K) of 100 g of water when 2kJ of heat is supplied to it is:

1. 4.8 K
2. 5.2 K
3. 2.4 K
4. 3.6 K

Q. Which has maximum internal energy at $290K$?

1. Neon gas
2. Nitrogen gas
3. Ozone gas
4. Helium gas

Q.

1. true
2. false

Q. Two moles of an ideal gas is heated at constant pressure of one atomsphere from ${27}^{\circ }C$ to ${127}^{\circ }C.$ if $C_{v,m}=20+{10}^{-2}T$ $J{K}^{-1}mo{l}^{-1}$ then Heat (q) and Internal energy ($△U$) for the process are respectively:

1. 7062.8 J, 5400 J
2. 3181.4 J, 2350 J
3. 6362.8 J, 4700 J
4. 3037.2 J, 4700 J

Q. A container is filled with 20 moles of an ideal diatomic gas at absolute temperature T. When heat is suppliedto gas temperature remains constant but 8 moles dissociate into atoms. Heat energy given to gas is (1) 4RT (2) 6RT (3) 3RT (4) 5RT

Q. Calculate the number of $kJ$ of heat necessary to raise the temperature of $60.0g$ of aluminium from ${35}^{o}C$ to ${55}^{o}C$. Molar heat capacity of $Al$ is $24J{mol}^{-1}{K}^{-1}$.

Q. When 229 J of energy is supplied as heat at constant pressure to 3 mol Ar(g), the temperature of the sample is increased by 2.55K. Calculate the molar heat capacity at constant volume:

1. $30kJ{K}^{-1}{mol}^{-1}$
2. $30J{K}^{-1}{mol}^{-1}$
3. $21.7J{K}^{-1}{mol}^{-1}$
4. $21.7KJ{K}^{-1}{mol}^{-1}$

Q.

Which of the following statement is true for a thermodynamical system where $∆U$ is the increase in internal energy and $∆W$ work done respectively?

1. $∆U=-∆W$ in isothermal process

2. $∆U=∆W$ in isothermal process

3. $∆U=-∆W$ in an adiabatic process

4. $∆U=∆W$ in an adiabatic process

Q. Statement I
Water boils at a lower temperature at high altitudes compared to low altitudes
Because
Statement II
The vapor pressure of water is lower at higher altitude

1. Both the Statement 1 and Statement 2 are correct and Statement 2 is not the correct explanation of Statement 1.
2. Statement 1 and Statement 2 are correct and Statement 2 is the correct explanation of Statement 1
3. Both the Statement 1 and Statement 2 are not correct.
4. Statement 1 is correct but Statement 2 is not correct.
5. Statement 1 is not correct but Statement 2 is correct.

Q.

Define specific heat capacity and state its units.

Q. For a diatomic gas undergoing a reversible process with its pressure inversely proportional to absolute temperature, its molar heat capacity is $\frac{xR}{2}$. The value of $x$ is:

1. $9$
2. $7$
3. $12$
4. $8$

Q. What is specific heat?