1
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)
2
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
3
JEE Main 2020 (Online) 6th September Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
For the given cell :

Cu(s) | Cu2+(C1M) || Cu2+(C2M) | Cu(s)

change in Gibbs energy ($$\Delta $$G) is negative, if :
A
C2 = $$\sqrt 2 $$C1
B
C2 = $${{{C_1}} \over {\sqrt 2 }}$$
C
C1 = 2C2
D
C1 = C2
4
JEE Main 2020 (Online) 6th September Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
A set of solutions is prepared using 180 g of water as a solvent and 10 g of different nonvolatile solutes A, B and C. The relative lowering of vapour pressure in the presence of these solutes are in the order :

[Given, molar mass of A = 100 g mol–1; B = 200 g mol–1; C = 10,000 g mol–1]
A
A > C > B
B
C > B > A
C
A > B > C
D
B > C > A
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