2020
JEE Mains
MCQ
JEE Main 2020 (Online) 9th January Morning Slot
If enthalpy of atomisation for Br2(1) is x kJ/mol
and bond enthalpy for Br2 is y kJ/mol, the
relation between them :
A.
does not exist
B.
is x < y
C.
is x > y
D.
is x = y
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 12th April Morning Slot
An ideal gas is allowed to expand form 1 L to 10 L against a constant external pressure of I bar. The work
done in kJ is :
A.
+10.0
B.
–0.9
C.
– 2.0
D.
– 9.0
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 12th April Morning Slot
Enthalpy of sublimation of iodine is 24 cal g–1
at 200 oC. If specific heat of I2(s) and l2 (vap) are 0.055 and
0.031 cal g–1K
–1
respectively, then enthalpy of sublimation of iodine at 250 oC in cal g–1
is :
A.
2.85
B.
22.8
C.
11.4
D.
5.7
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 10th April Evening Slot
The difference between $\Delta $H and $\Delta $U ($\Delta $H – $\Delta $U), when the combustion of one mole of heptane(l) is carried
out at a temperature T, is equal to :
A.
– 4 RT
B.
3 RT
C.
– 3 RT
D.
4 RT
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 10th April Morning Slot
A process will be spontaneous at all temperatures if :
A.
$\Delta $H < 0 and $\Delta $S > 0
B.
$\Delta $H < 0 and $\Delta $S < 0
C.
$\Delta $H > 0 and $\Delta $S < 0
D.
$\Delta $H > 0 and $\Delta $S > 0
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 9th April Evening Slot
During compression of a spring the work done
is 10kJ and 2kJ escaped to the surroundings as
heat. The change in internal energy, $\Delta $U(inkJ)
is :
A.
- 12
B.
8
C.
- 8
D.
12
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 9th April Morning Slot
Among the following, the set of parameters that
represents path function, is :
(A) q + w
(B) q
(C) w
(D) H–TS
(A) q + w
(B) q
(C) w
(D) H–TS
A.
(B) and (C)
B.
(A) and (D)
C.
(B), (C) and (D)
D.
(A), (B) and (C)
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 8th April Evening Slot
5 moles of an ideal gas at 100 K are allowed
to undergo reversible compression till its
temperature becomes 200 K.
If CV = 28 JK–1mol–1, calculate $\Delta $U and $\Delta $pV for
this process. (R = 8.0 JK–1 mol–1]
A.
$\Delta $U = 14 kJ; $\Delta $(pV) = 4 kJ
B.
$\Delta $U = 2.8 kJ; $\Delta $(pV) = 0.8 kJ
C.
$\Delta $U = 14 kJ; $\Delta $(pV) = 18 kJ
D.
$\Delta $U = 14 kJ; $\Delta $(pV) = 0.8 kJ
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 8th April Morning Slot
Which one of the following equations does not correctly represent the first law of thermodynamics
for the given processes involving an ideal gas? (Assume non-expansion work is zero)
A.
Adiabatic process : $\Delta $U= – w
B.
Cyclic process : q = –w
C.
Isochoric process : $\Delta $U= q
D.
Isothermal process : q = – w
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 8th April Morning Slot
For silver, Cp(J K–1 mol–1) = 23 +0.01 T. If the temperature (T) of 3 moles of silver is raised from 300
K to 1000 K at 1 atm pressure, the value of $\Delta H$ will be close to :
A.
62 KJ
B.
16 KJ
C.
13 KJ
D.
21 KJ
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 12th January Evening Slot
Given
(i) C (graphite) + O2(g) $ \to $ CO2(g); $\Delta $rH$^\Theta $ = x kJ mol$-$1
(ii) C(graphite) + ${1 \over 2}$O2(g) $ \to $ CO(g); $\Delta $rH$^\Theta $ = y kJ mol$-$1
(iii) CO(g) + ${1 \over 2}$ O2(g) $ \to $ CO2(g); $\Delta $rH$^\Theta $ = z kJ mol$-$1
Based on the above thermochemical equations, find out which one of the following algebraic relationships is correct?
(i) C (graphite) + O2(g) $ \to $ CO2(g); $\Delta $rH$^\Theta $ = x kJ mol$-$1
(ii) C(graphite) + ${1 \over 2}$O2(g) $ \to $ CO(g); $\Delta $rH$^\Theta $ = y kJ mol$-$1
(iii) CO(g) + ${1 \over 2}$ O2(g) $ \to $ CO2(g); $\Delta $rH$^\Theta $ = z kJ mol$-$1
Based on the above thermochemical equations, find out which one of the following algebraic relationships is correct?
A.
z = x + y
B.
x = y + z
C.
x = y – z
D.
y = 2z – x
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 12th January Evening Slot
The combination of plots which does not represent isothermal expansion of an ideal gas is –
A.
A and D
B.
B and D
C.
B and C
D.
A and C
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 12th January Morning Slot
For diatomic ideal gas in a closed system, which of the following plots does not correctly describe the relation between various thermodynamic quantities?
A.
B.
C.
D.
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 11th January Evening Slot
The reaction, MgO(s) + C(s) $ \to $ Mg(s) + CO(g), for which $\Delta $rHo + 491.1 kJ mol–1 and $\Delta $rSo = 198.0 JK–1 mol–1, is not feasible at 298 K. Temperature above which reaciton will be feasible is :
A.
2480.3 K
B.
2040.5 K
C.
2380.5 K
D.
1890.0 K
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 11th January Evening Slot
For the equilibrium,
2H2O $\rightleftharpoons$ H3O+ + OH$-$, the value of $\Delta $Go at 298 K is approximately :
2H2O $\rightleftharpoons$ H3O+ + OH$-$, the value of $\Delta $Go at 298 K is approximately :
A.
$-$ 80 kJ mol–1
B.
100 kJ mol$-$1
C.
$-$ 100 kJ mol$-$1
D.
80 kJ mol–1
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 11th January Evening Slot
The standard reaction Gibbs energy for a chemical reaction at an absolute temperature T is given by
$\Delta $rGo = A – BT
Where A and B are non-zero constants. Which of the following is TRUE about this reaction?
Where A and B are non-zero constants. Which of the following is TRUE about this reaction?
A.
Exothermic if B < 0
B.
Endothermic if A > 0
C.
Exothermic if A > 0 and B < 0
D.
Endothermic if A < 0 and B > 0
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 11th January Morning Slot
For the chemical reaction X $\rightleftharpoons$ Y, the standard reaction Gibbs energy depends on temperature T (in K) as
$\Delta $rGo (in kJ mol–1) = 120 $ - {3 \over 8}$ T.
The major component of the reaction mixture at T is :
The major component of the reaction mixture at T is :
A.
Y if T = 300 K
B.
Y if T = 280 K
C.
X if T = 350 K
D.
X if T = 315 K
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 11th January Morning Slot
Two blocks of the same metal having same mass and at temperature T1 and T2, respectively, are brought in contact with each other and allowed to attain thermal equilibrium at constant pressure. The change in entropy, $\Delta $S, for this process is :
A.
2Cp In $\left[ {{{{{\left( {{T_1} + {T_2}} \right)}^{{1 \over 2}}}} \over {{T_1}{T_2}}}} \right]$
B.
2Cp In $\left[ {{{\left( {{T_1} + {T_2}} \right)} \over {2{T_1}{T_2}}}} \right]$
C.
Cp In $\left[ {{{{{\left( {{T_1} + {T_2}} \right)}^2}} \over {4{T_1}{T_2}}}} \right]$
D.
2Cp In $\left[ {{{\left( {{T_1} + {T_2}} \right)} \over {4{T_1}{T_2}}}} \right]$
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 10th January Evening Slot
The process with negative entropy change is :
A.
Dissociation of CaSO4 (s) to CaO(s) and SO3(g)
B.
Dissolution of iodine in water
C.
Synthesis of ammonia from N2 and H2
D.
Sublimation of dry ice
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 10th January Evening Slot
An ideal gas undergoes isothermal compression from 5m3 to 1 m3 against a constant external pressure of 4 Nm–2. Heat released in this process is used to increase the temperature of 1 mole of Al. If molar heat capacity of Al is 24 J mol–1 K–1, the temperature of Al increases by :
A.
${2 \over 3}K$
B.
${3 \over 2}K$
C.
1 K
D.
2 K
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 10th January Morning Slot
A process has $\Delta $H = 200 J mol–1 and $\Delta $S = 40 JK–1 mol–1. Out of the values given below, choose the minimum temperature above which the process will be spontaneous :
A.
4 K
B.
20 K
C.
5 K
D.
12 K
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 9th January Evening Slot
The entropy change associated with the conversion of 1 kg of ice at 273 K to water vapours at 383 K is :
(Specific heat of water liquid and water vapour are 4.2 kJ K$-$1 kg$-$1 and 2.0 kJ K$-$1 kg$-$1; heat of liquid fusion and vapourisation of water are 334 kJ$-$1 and 2491 kJ kg$-$1, respectively). (log 273 = 2.436, log 373 = 2.572, log 383 = 2.583)
(Specific heat of water liquid and water vapour are 4.2 kJ K$-$1 kg$-$1 and 2.0 kJ K$-$1 kg$-$1; heat of liquid fusion and vapourisation of water are 334 kJ$-$1 and 2491 kJ kg$-$1, respectively). (log 273 = 2.436, log 373 = 2.572, log 383 = 2.583)
A.
7.90 kJ kg$-$1 K$-$1
B.
2.64 kJ kg$-$1 K$-$1
C.
8.49 kJ kg$-$1 K$-$1
D.
9.26 kJ kg$-$1 K$-$1
2019
JEE Mains
MCQ
JEE Main 2019 (Online) 9th January Morning Slot
Consider the reversible isothermal expansion of an ideal gas in a closed system at two different temperatures T1 and T2 (T1 < T2). The correct graphical depiction of the dependence of work done (w) on the final volume (V) is :
A.
B.
C.
D.
2018
JEE Mains
MCQ
JEE Main 2018 (Online) 16th April Morning Slot
For which of the following processes, $\Delta $S is negative ?
A.
H2(g) $ \to $ 2H(g)
B.
N2(g, 1 atm) $ \to $ N2(g, 5 atm)
C.
C(diamond) $ \to $ C(graphite)
D.
N2(g, 273 K) $ \to $ N2(g, 300 K)
2018
JEE Mains
MCQ
JEE Main 2018 (Online) 16th April Morning Slot
At 320 K, a gas A2 is 20% dissociated to A(g). The standard free energy change at 320 K and 1 atm in J mol-1 is approximately : (R = 8.314 JK-1 mol-1; ln2 = 0.693; ln 3 = 1.098)
A.
4763
B.
2068
C.
1844
D.
4281
2018
JEE Mains
MCQ
JEE Main 2018 (Offline)
Which of the following lines correctly show the temperature dependence of equilibrium constant K, for an
exothermic reaction?
A.
A and D
B.
A and B
C.
B and C
D.
C and D
2018
JEE Mains
MCQ
JEE Main 2018 (Offline)
The combustion of benzene(l) gives CO2(g) and H2O(l). Given that heat of combustion of benzene at constant volume is –3263.9 kJ mol–1 at 25oC; heat of combustion (in kJ mol–1) of benzene at constant pressure will be :
(R = 8.314 JK–1 mol–1)
(R = 8.314 JK–1 mol–1)
A.
–3267.6
B.
4152.6
C.
–452.46
D.
3260
2018
JEE Mains
MCQ
JEE Main 2018 (Online) 15th April Evening Slot
Given
(i) 2Fe2O3(s) $ \to $ 4Fe(s) + 3O2(g);
$\Delta $rGo = + 1487.0 kJ mol-1
(ii) 2CO(g) + O2(g) $ \to $ 2CO2(g);
$\Delta $rGo = $-$ 514.4 kJ mol-1
Free energy change, $\Delta $rGo for the reaction
2Fe2O3(s) + 6CO(g) $ \to $ 4Fe(s) + 6CO2(g) will be :
(i) 2Fe2O3(s) $ \to $ 4Fe(s) + 3O2(g);
$\Delta $rGo = + 1487.0 kJ mol-1
(ii) 2CO(g) + O2(g) $ \to $ 2CO2(g);
$\Delta $rGo = $-$ 514.4 kJ mol-1
Free energy change, $\Delta $rGo for the reaction
2Fe2O3(s) + 6CO(g) $ \to $ 4Fe(s) + 6CO2(g) will be :
A.
$-$ 112.4 kJ mol-1
B.
$-$ 56.2 kJ mol-1
C.
$-$ 168.2 kJ mol-1
D.
$-$ 208.0 kJ mol-1
2018
JEE Mains
MCQ
JEE Main 2018 (Online) 15th April Evening Slot
$\Delta $fGo at 500 K for substance 'S' in liquid state and gaseous state are +100.7 kcl mol-1 and +103 kcal mol-1, respectively. Vapour pressure of liquid 'S' at 500 K is approximately equal to : ( R = 2 cal K-1 mol-1 )
A.
0.1 atm
B.
1 atm
C.
10 atm
D.
100 atm
2018
JEE Mains
MCQ
JEE Main 2018 (Online) 15th April Morning Slot
An ideal gas undergoes a cyclic process as shown in Figure.
$\Delta $UBC = $-$5 kJ mol-1, qAB = $2$ kJ mol-1, WAB = $-$5 kJ mol-1, WCA = 3 kJ mol-1. Heat absorbed by the system during process $CA$ is :
$\Delta $UBC = $-$5 kJ mol-1, qAB = $2$ kJ mol-1, WAB = $-$5 kJ mol-1, WCA = 3 kJ mol-1. Heat absorbed by the system during process $CA$ is :
A.
$-$5 kJ mol-1
B.
+5 kJ mol-1
C.
18 kJ mol-1
D.
$-$18 kJ mol-1
2018
JEE Mains
MCQ
JEE Main 2018 (Online) 15th April Morning Slot
For which of the following reactions, $\Delta $H is equal to $\Delta $U?
A.
N2(g) + 3H2(g) $ \to $ 2NH3(g)
B.
2HI(g) $ \to $ H2(g) + I2(g)
C.
2NO2(g) $ \to $ N2O4(g)
D.
2SO2(g) + O2(g) $ \to $ 2SO3(g)
2017
JEE Mains
MCQ
JEE Main 2017 (Online) 9th April Morning Slot
A gas undergoes change from state A to state B. In this process, the heat absorbed
and work done by the gas is 5 J and 8 J, respectively. Now gas is brought back to
A by another process during which 3 J of heat is evolved. In this reverse process of
B to A :
A.
10 J of the work will be done by the gas.
B.
6 J of the work will be done by the gas.
C.
10 J of the work will be done by the surrounding on gas.
D.
6 J of the work will be done by the surrounding on gas.
2017
JEE Mains
MCQ
JEE Main 2017 (Online) 9th April Morning Slot
An ideal gas undergoes isothermal expansion at constant pressure. During
the process :
A.
enthalpy increases but entropy decreases.
B.
enthalpy remains constant but entropy increases.
C.
enthalpy decreases but entropy increases.
D.
Both enthalpy and entropy remain constant.
2017
JEE Mains
MCQ
JEE Main 2017 (Online) 8th April Morning Slot
The enthalpy change on freezing of 1 mol of water at 5oC to ice at −5oC is :
(Given $\Delta $fusH = 6 kJ mol$-$1 at 0oC,
Cp(H2O, $\ell $ = 75.3J mol$-$1 K$-$1)
Cp(H2O s) =36.8 J mol$-$1 K$-$1)
(Given $\Delta $fusH = 6 kJ mol$-$1 at 0oC,
Cp(H2O, $\ell $ = 75.3J mol$-$1 K$-$1)
Cp(H2O s) =36.8 J mol$-$1 K$-$1)
A.
5.44 kJ mol$-$1
B.
5.81 kJ mol$-$1
C.
6.56 kJ mol$-$1
D.
6.00 kJ mol$-$1
2017
JEE Mains
MCQ
JEE Main 2017 (Online) 8th April Morning Slot
For a reaction, A(g) $ \to $ A($\ell $); $\Delta $H= $-$ 3RT.
The correct statement for the reaction is :
The correct statement for the reaction is :
A.
$\Delta $H = $\Delta $U $ \ne $ O
B.
$\Delta $H = $\Delta $U = O
C.
$\left| {} \right.$$\Delta $H$\left| {} \right.$ < $\left| {} \right.$$\Delta $U$\left| {} \right.$
D.
$\left| {} \right.$$\Delta $H$\left| {} \right.$ > $\left| {} \right.$$\Delta $U$\left| {} \right.$
2017
JEE Mains
MCQ
JEE Main 2017 (Offline)
$\Delta $U is equal to :
A.
Isobaric work
B.
Adiabatic work
C.
Isothermal work
D.
Isochoric work
2017
JEE Mains
MCQ
JEE Main 2017 (Offline)
Given, ${C_{(graphite)}} + {O_2} \to C{O_2}(g)$;
${\Delta _r}{H^o}$ = - 393.5 kJ mol-1
${{\rm H}_2}(g)$ + ${1 \over 2}{O_2}(g)$$\to {{\rm H}_2}{\rm O}(l)$
${\Delta _r}{H^o}$ = - 285.8 kJ mol-1
$C{O_2}(g)$ + $2{{\rm H}_2}{\rm O}(l) \to$ $C{H_4}(g)$ + $2{O_2}(g)$
${\Delta _r}{H^o}$ = + 890.3 kJ mol-1
Based on the above thermochemical equations, the value of ${\Delta _r}{H^o}$ at 298 K for the reaction
${C_{(graphite)}}$ + $2{{\rm H}_2}(g) \to$ $C{H_4}(g)$ will be :
${\Delta _r}{H^o}$ = - 393.5 kJ mol-1
${{\rm H}_2}(g)$ + ${1 \over 2}{O_2}(g)$$\to {{\rm H}_2}{\rm O}(l)$
${\Delta _r}{H^o}$ = - 285.8 kJ mol-1
$C{O_2}(g)$ + $2{{\rm H}_2}{\rm O}(l) \to$ $C{H_4}(g)$ + $2{O_2}(g)$
${\Delta _r}{H^o}$ = + 890.3 kJ mol-1
Based on the above thermochemical equations, the value of ${\Delta _r}{H^o}$ at 298 K for the reaction
${C_{(graphite)}}$ + $2{{\rm H}_2}(g) \to$ $C{H_4}(g)$ will be :
A.
+144.0 kJ mol–1
B.
– 74.8 kJ mol–1
C.
-144.0 kJ mol–1
D.
+ 74.8 kJ mol–1
2016
JEE Mains
MCQ
JEE Main 2016 (Online) 10th April Morning Slot
If 100 mole of H2O2 decompose at 1 bar and 300 K, the work done (kJ) by one mole of O2(g) as it expands against 1 bar pressure is :
2H2O2(l) $\rightleftharpoons$ 2H2O(l) + O2(g)
(R = 8.3 J K $-$1 mol$-$1)
2H2O2(l) $\rightleftharpoons$ 2H2O(l) + O2(g)
(R = 8.3 J K $-$1 mol$-$1)
A.
62.25
B.
124.50
C.
249.00
D.
498.00
2016
JEE Mains
MCQ
JEE Main 2016 (Online) 9th April Morning Slot
The plot shows the variation of −$ln$ Kp versus temperature for the two reactions.
M(s) + ${1 \over 2}$ O2(g) $ \to $ MO(s) and
C(s) + ${1 \over 2}$ O2(g) $ \to $ CO(s)
Identify the correct statement :
M(s) + ${1 \over 2}$ O2(g) $ \to $ MO(s) and
C(s) + ${1 \over 2}$ O2(g) $ \to $ CO(s)
Identify the correct statement :
A.
At T > 1200 K, carbon will reduce MO(s) to M(s).
B.
At T < 1200 K, the reaction
MO(s) + C(s) $ \to $ M(s) + CO(g) is spontaneous.
MO(s) + C(s) $ \to $ M(s) + CO(g) is spontaneous.
C.
At T < 1200 K, oxidation of carbon is unfavourable
D.
Oxidation of carbon is favourable at all temperatures.
2016
JEE Mains
MCQ
JEE Main 2016 (Online) 9th April Morning Slot
A reaction at 1 bar is non-spontaneous at low temperature but becomes spontaneous
at high temperature. Identify the correct statement about the reaction among the
following :
A.
Both $\Delta $H and $\Delta $S are negative.
B.
Both $\Delta $H and $\Delta $S are positive.
C.
$\Delta $H is positive while $\Delta $S is negative.
D.
$\Delta $H is negative while $\Delta $S is positive.
2016
JEE Mains
MCQ
JEE Main 2016 (Online) 9th April Morning Slot
For the reaction,
A(g) + B(g) $ \to $ C(g) + D(g), $\Delta $Ho and $\Delta $So are, respectively, − 29.8 kJ mol−1 and −0.100 kJ K−1 mol−1 at 298 K. The equilibrium constant for the reaction at 298 K is :
A(g) + B(g) $ \to $ C(g) + D(g), $\Delta $Ho and $\Delta $So are, respectively, − 29.8 kJ mol−1 and −0.100 kJ K−1 mol−1 at 298 K. The equilibrium constant for the reaction at 298 K is :
A.
1.0 $ \times $ 10$-$10
B.
1.0 $ \times $ 1010
C.
10
D.
1
2016
JEE Mains
MCQ
JEE Main 2016 (Offline)
The heats of combustion of carbon and carbon monoxide are –393.5 and –283.5 kJ mol–1, respectively. The
heat of formation (in kJ) of carbon monoxide per mole is :
A.
676.5
B.
-676.5
C.
–110
D.
110.5
2015
JEE Mains
MCQ
JEE Main 2015 (Offline)
The following reaction is performed at 298 K
2NO(g) + O2 (g) $\leftrightharpoons$ 2NO2 (g)
The standard free energy of formation of NO(g) is 86.6 kJ/mol at 298 K. What is the standard free energy of formation of NO2(g) at 298 K? (KP = 1.6 × 1012)
2NO(g) + O2 (g) $\leftrightharpoons$ 2NO2 (g)
The standard free energy of formation of NO(g) is 86.6 kJ/mol at 298 K. What is the standard free energy of formation of NO2(g) at 298 K? (KP = 1.6 × 1012)
A.
86600 + R(298) ln(1.6 $\times$ 1012)
B.
86600 - $ln (1.6 \times 10^{12}) \over R (298)$
C.
0.5[2×86,600 – R(298) ln(1.6×1012)]
D.
R(298) ln(1.6×1012) – 86600
2014
JEE Mains
MCQ
JEE Main 2014 (Offline)
For complete combustion of ethanol, C2H5OH(l) + 3O2(g) $\to$ 2CO2(g) + 3H2O(l) the amount of heat
produced as measured in bomb calorimeter, is 1364.47 kJ mol–1 at 25oC. Assuming ideality the Enthalpy of combustion, $\Delta _CH$, for the reaction will be : (R = 8.314 kJ mol–1)
A.
–1460.50 kJ mol–1
B.
– 1350.50 kJ mol–1
C.
– 1366.95 kJ mol–1
D.
– 1361.95 kJ mol–1
2013
JEE Mains
MCQ
JEE Main 2013 (Offline)
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 208J of heat. The values of q and w for the process will be :
(R = 8.314 J/mol K) ( l n 7.5 = 2.01)
(R = 8.314 J/mol K) ( l n 7.5 = 2.01)
A.
q = – 208 J, w = – 208 J
B.
q = – 208 J, w = + 208 J
C.
q = + 208 J, w = + 208 J
D.
q = + 208 J, w = – 208 J
2012
JEE Mains
MCQ
AIEEE 2012
The incorrect expression among the following is :
A.
${{\Delta {G_{system}}} \over {\Delta {S_{total}}}} = - T$
B.
In isothermal process ${w_{reversible}}$ = $ - nRT\,\ln \,{{{V_f}} \over {{V_i}}}$
C.
In $K\, = {{\Delta {H^o} - T\Delta {S^o}} \over {RT}}$
D.
$K\, = \,{e^{ - \Delta {G^o}/RT}}$
2011
JEE Mains
MCQ
AIEEE 2011
The entropy change involved in the isothermal reversible expansion of 2 moles of an ideal gas from a
volume of 10 dm3 to a volume of 100 dm3 at 27oC is :
A.
35.8 J mol-1 K−1
B.
32.3 J mol-1 K−1
C.
42.3 J mol-1 K−1
D.
38.3 J mol-1 K−1
2010
JEE Mains
MCQ
AIEEE 2010
For a particular reversible reaction at temperature T, ∆H and ∆S were found to be both +ve. If Te is
the temperature at equilibrium, the reaction would be spontaneous when :
A.
Te > T
B.
T > Te
C.
Te is 5 times T
D.
T = Te
2010
JEE Mains
MCQ
AIEEE 2010
The standard enthalpy of formation of NH3 is –46.0 kJ mol–1. If the enthalpy of formation of H2 from its atoms is –436 kJ mol–1 and that of N2 is –712 kJ mol–1, the average bond enthalpy of N–H bond in NH3 is :
A.
–964 kJ mol–1
B.
+352 kJ mol–1
C.
+ 1056 kJ mol–1
D.
–1102 kJ mol–1
2009
JEE Mains
MCQ
AIEEE 2009
On the basis of the following thermochemical data :
($\Delta _fG^oH^+_{(aq)}$ = 0)
H2O(l) $\to$ H+(aq) + OH-(aq); $\Delta H$ = 57.32 kJ
H2(g) + ${1 \over 2} O_2(g) \to$ H2O(l); $\Delta H$ = -286.20 kJ
The value of enthalpy of formation of OH− ion at 25oC is :
($\Delta _fG^oH^+_{(aq)}$ = 0)
H2O(l) $\to$ H+(aq) + OH-(aq); $\Delta H$ = 57.32 kJ
H2(g) + ${1 \over 2} O_2(g) \to$ H2O(l); $\Delta H$ = -286.20 kJ
The value of enthalpy of formation of OH− ion at 25oC is :
A.
-22.88 kJ
B.
-228.88 kJ
C.
+228.88 kJ
D.
-343.52 kJ