(298K) of methanol is given by the chemical equation:
1. \(\mathrm{C}(\text { diamond })+\frac{1}{2} \mathrm{O}_{2(\mathrm{~g})}+2 \mathrm{H}_{2(\mathrm{~g})} \rightarrow \mathrm{CH}_3 \mathrm{OH}_{(\mathrm{l})}\)
2. \(\mathrm{CH}_{4(\mathrm{~g})}+\frac{1}{2} \mathrm{O}_{2(\mathrm{~g})} \rightarrow \mathrm{CH}_3 \mathrm{OH}_{(\mathrm{g})}\)
3. \(\mathrm{CO}_{(\mathrm{g})}+2 \mathrm{H}_{2(\mathrm{~g})} \rightarrow \mathrm{CH}_3 \mathrm{OH}_{(\mathrm{l})}\)
4. \(\mathrm{C}(\text { graphite })+\frac{1}{2} \mathrm{O}_{2(\mathrm{~g})}+2 \mathrm{H}_{2(\mathrm{~g})} \rightarrow \mathrm{CH}_3 \mathrm{OH}_{(\mathrm{l})}\)
A piston filled with 0.04 mol of an ideal gas expands reversibly from 50.0 mL to 375 mL at a constant temperature of 37.0ºC. As it does so, it absorbs 208 J of heat. The values of q and w for the process will be-
(R = 8.314 J/mol K) (ln 7.5 = 2.01)
1. | q = +208 J, w = -208 J | 2. | q = -208 J, w = -208 J |
3. | q = -208 J, w = + 208 J | 4. | q = +208 J, w = + 208 J |
Entropy decreases during:
1. Crystallization of sucrose from solution
2. Rusting of iron
3. Melting of ice
4. Vaporization of camphor
Change in entropy is negative for:
1. Bromine (l)Bromine(g)
2. C(s) + H2O(g) CO(g) + H2(g)
3. N2(g,10 atm)N2(g,1 atm)
4. Fe ( 1mol, 400 K) Fe( 1mol, 300 K)
For the following given equations and values, determine the enthalpy of reaction at 298 K for the reaction:
C2H4(g) + 6F2(g) 2CF4(g) + 4HF(g)
H2(g) + F2(g) 2HF(g) = -537 kJ
C(s) + 2F2(g) CF4(g) =-680 kJ
2C(s) + 2H2(g) C2H4(g) = 52 kJ
1. -1165 kJ
2. -2486 kJ
3. +1165 kJ
4. +2486 kJ
The entropy change in the isothermal reversible expansion of 2 moles of an ideal gas from 10 to 100 L at 300 K is
1.
2.
3.
4.
As an isolated box, equally partitioned, contains two ideal gasses A and B as shown:
When the partition is removed, the gases mix. The changes in enthalpy and entropy in the process, respectively, are
1. Zero, positive
2. Zero, negative
3. Positive, zero
4. Negative, zero
When 4 g of iron is burnt to ferric oxide at a constant pressure, 29.28 kJ of heat is evolved.
The enthalpy of formation of ferric oxide will be-
(At. mass of Fe = 56) ?
1. 81.98 kJ
2. 819.8 kJ
3. 40.99 kJ
4. +819.8 kJ
1. 1.968 V
2. 2.0968 V
3. 1.0968 V
4. 0.0968 V
The values of ΔH and ΔS for the given reaction are 170 kJ and 170 JK-1, respectively.
C(graphite) + CO2(g)→2CO(g)
This reaction will be spontaneous at:
1. 710 K
2. 910 K
3. 1110 K
4. 510 K