1
JEE Main 2020 (Online) 6th September Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
The average molar mass of chlorine is 35.5 g mol–1. The ratio of 35Cl to 37Cl in naturally occuring chlorine is close to :
A
1 : 1
B
2 : 1
C
3 : 1
D
4 : 1
2
JEE Main 2020 (Online) 6th September Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
The value of KC is 64 at 800 K for the reaction

N2(g) + 3H2(g) ⇌ 2NH3(g)

The value of KC for the following reaction is :

NH3(g) ⇌ $${1 \over 2}$$N2(g) + $${3 \over 2}$$H2(g)
A
8
B
$${1 \over 8}$$
C
$${1 \over 4}$$
D
$${1 \over {64}}$$
3
JEE Main 2020 (Online) 6th September Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
For a reaction,
4M(s) + nO2(g) $$ \to $$ 2M2On(s)
the free energy change is plotted as a function of temperature. The temperature below which the oxide is stable could be inferred from the plot as the point at which :
A
the free energy change shows a change from negative to positive value
B
the slope changes from positive to negative
C
the slope changes from negative to positive
D
the slope changes from positive to zero
4
JEE Main 2020 (Online) 6th September Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
The correct match between Item-I (starting material) and Item-II (reagent) for the preparation of benzaldehyde is :

Item-I Item-II
(I) Benzene (P) HCl and SnCl2, H3O+
(II) Benzonitrile (Q) H2, Pd-BaSO4, S and quinoline
(III) Benzoyl Chloride (R) CO, HCl and AlCl3
A
(I) - (R), (II) - (P) and (III) - (Q)
B
(I) - (P), (II) - (Q) and (III) - (R)
C
(I) - (Q), (II) - (R) and (III) - (P)
D
(I) - (R), (II) - (Q) and (III) - (P)

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