JEE Main, NEET MCQs Set 9

Sr. No.

Question

Answer

1.

For alkali metals, which one of the following trends is INCORRECT?

(A) Ionization energy: Li > Na > K > Rb

(B) Hydration energy: Li > Na > K > Rb

(C) Atomic size: Li < Na < K < Rb

(D) Density: Li < Na < K < Rb

Answer: (D)

2.

For one mole of an ideal gas, increasing the temperature from 10°C to 20°C ______.

(A) increases the rms velocity by times.

(B) increases the average kinetic energy by two times.

(C) increases both the average kinetic energy and rms velocity, but not significantly.

(D) increases the rms velocity by two times.

Answer: (C)

3.

For the decomposition of a compound AB at 600 K, the following data were obtained:

The order for the decomposition of AB is

(A) 1

(B) 2

(C) 1.5

(D) 0

Answer: (B)

4.

For the four successive transition elements (Cr, Mn, Fe and Co), the stability of + 2 oxidation state will be there in which of the following order?

(A) Cr > Mn > Co > Fe

(B) Mn > Fe > Cr > Co

(C) Fe > Mn > Co > Cr

(D) Co > Mn > Fe > Cr

(At. nos. Cr = 24, Mn = 25, Fe = 26, Co = 27)

Answer: (B)

5.

For the reaction 2HI_(g) ⇌ H_2(g) + I_2(g) – Q KJ , the equilibrium constant depends upon

(A) temperature

(B) pressure

(C) catalyst

(D) volume

Answer: (A)

6.

For the reaction Fe₂O₃ + 3CO → 2Fe + 3CO₂ the volume of carbon monoxide required to reduce one mole of ferric oxide is

(A) 22.4 dm³

(B) 44.8 dm³

(C) 67.2 dm³

(D) 11.2 dm³

Answer: (C)

7.

For the reaction H₂O (l) ⇌ H₂O(g) at 373 K and one atmospheric pressure

(A) ΔH = TΔS

(B) ΔH = ΔE

(C) ΔH = 0

(D) ΔE = 0

Answer: (A)

8.

For the reaction N₂(g) +  O₂(g) ⇌ 2NO(g), the equilibrium constant is K₁.
The equilibrium constant is K₂ for the reaction 2NO(g) + O₂(g) ⇌ 2NO₂(g).
What is K for the reaction NO₂(g) ⇌  N₂(g) + O₂(g)?

(A)

(B)

(C)

(D)

Answer: (D)

9.

For the reversible reaction

A_(s) +B_(g) ⇌ C_(g) + D_(g): DG⁰ = –350kJ.

Which one of the following statements is true?

(A) Equilibrium constant is greater than one.

(B) The entropy change is negative.

(C) The reaction is thermodynamically not feasible.

(D) The reaction should be instantaneous.

Answer: (A)

10.

Formation of coloured solution is possible when metal ion in the compound contains

(A) paired electrons

(B) unpaired electrons

(C) lone pair of electrons

(D) none of these

Answer: (B)