Question

On catalytic hydrogenation ethylene gives ethane. During this reaction

hybridization of carbon atoms changes from SP² to SP³

bond angle decreases from 120 to 109.5

C-C Bond length increases from 1.34 A° to 1.54 A°

all of these

Answer 1

Option A:
hybridization is given by no of sigma bonds present, so in ethylene 3 sigma bonds are there and in ethane 4 sigma bonds are there thus hybridization of ethylene is sp2 and of ethane is sp3.
Therefore option A is correct.

Option B:
Ethylene is trigonal planar in shape and have bond angle 120, while ethane is tetrahedral and have cond angle 109.5. Therefore option B is correct.

Option C:
In ethylene bond length is 133.005A (almost equal to 134) and in ethane bond length is 1.54A. thus option C is also correct.

From all this we can say that last option (all of these) is correct option.