1
COMEDK 2026 Afternoon Shift
MCQ (Single Correct Answer)
+1
-0

In the synthesis of $\mathrm{NH}_3$ from $\mathrm{H}_2$ and $\mathrm{N}_2$, if $6 \times 10^{-2}$ mole of hydrogen disappears in 10 minutes, the number of moles of $\mathrm{NH}_3$ formed in 0.3 minutes is:

A

$4.0 \times 10^{-3}$ moles

B

$6.0 \times 10^{-3}$ moles

C

$1.2 \times 10^{-3}$ moles

D

$1.5 \times 10^{-3}$ moles

2
COMEDK 2026 Afternoon Shift
MCQ (Single Correct Answer)
+1
-0

The element with the highest third ionisation enthalpy is:

A

Vanadium( $\mathrm{Z}=23$ )

B

Manganese ( $\mathrm{Z}=25$ )

C

Iron ( $\mathrm{Z}=26$ )

D

Chromium ( $\mathrm{Z}=24$ )

3
COMEDK 2026 Afternoon Shift
MCQ (Single Correct Answer)
+1
-0

$$ \text { When the concentration of the reactant in a given reaction is halved and if the rate of reaction is halved, the order of the reaction is: } $$

A

3

B

2

C

1

D

0

4
COMEDK 2026 Afternoon Shift
MCQ (Single Correct Answer)
+1
-0

Arrange the given alkanes in increasing order of their boiling points.

(A) 2, 2-dimethylpropane

(B) 2-methylbutane

(C) n-pentane

(D) n-butane

A

$D< A< B< C$

B

$C< A< B< D$

C

$D< C< B< A$

D

$A< B< C< D$