The standard enthalpy of vaporisation vapH for water at 100C is 40.66 kJ mol-1. The
internal energy of vaporisation of water at 100C (in kJ mol-1) is-
(Assume water vapour to behave like an ideal gas)
1. +37.56
2. -43.76
3. +43.76
4. +40.66
The enthalpy and entropy change for the reaction :
Br2 (l) + Cl2 (g) 2BrCl (g)
are 30 kJ mol-1 and 105 J K-1 mol-1 respectively.
The temperature at which the reaction will be in equilibrium is :
1. | 285.7 K | 2. | 273.4 K |
3. | 450.9 K | 4. | 300.1 K |
Which of the following is not a state function?
1. | ΔS | 2. | ΔG |
3. | ΔH | 4. | ΔQ |
The work done in ergs for the reversible expansion of one mole of an ideal gas from a volume of 10 liters to 20 liters at 25°C is -
1.
2.
3.
4.
For the reaction
\(C H_{3} C O O H \left(\right. l \left.\right)+ 2 O_{2} \left(\right. g \left.\right) \)
\(\rightleftharpoons 2 C O_{2} \left(\right. g \left.\right)+ 2 H_{2} O \left(\right. l \left.\right)\)
at 25°C and 1 atm. pressure, ΔH = –874 kJ. The change in internal energy (ΔE) is:
1. – 874 kJ
2. – 971.53 kJ
3. + 971.53 kJ
4. + 874 kJ
The occurrence of a reaction is impossible if:
1. ΔH is +ve ; ΔS is also + ve but ΔH < TΔS
2. ΔH is – ve ; ΔS is also – ve but ΔH > TΔS
3. ΔH is – ve ; ΔS is + ve
4. ΔH is + ve ; ΔS is – ve
The unit of entropy is -
1. J mol–1
2. JK mol–1
3. J mol–1 K–1
4. J–1 K–1 mol–1
Combustion of glucose takes place according to the equation,
,
Energy required for the production of 1.6 g of glucose is -
(Molecular mass of glucose = 180 g)
1. 0.064 kcal
2. 0.64 kcal
3. 6.4 kcal
4. 64 kcal
When a gas undergoes adiabatic expansion, it gets cooled due to -
1. Loss of energy
2. Fall in pressure
3. Decrease in velocity
4. Increase in energy with work done
A Beckmann thermometer is used to measure -
1. High temperature
2. Low temperature
3. Normal temperature
4. All temperatures