A. As wavelength increases, radiant energy and frequency increase.
Option (a) is correct.
A reducing agent is the one which loses electrons to other substance.
Here, Zn has oxidation number 0 in the L.H.S of the equation, but on R.H.S its oxidation number is +2 i.e. it Zn has donated two of its electrons to

.
Hence, Zn is the reducing agent here.
The molecular weight of the substance.
Answer:
graph 2
Explanation:
Graham's law:
∴v1: gas diffusion rate 1
∴ v2: gas diffusion rate 2
∴ M1: gas molecular weight 1
∴ M2: gas molecular weight 2
Let Y = R = v1/v2 and X = M2/M1
⇒ Y = √X
the graph for the function Y = √X; is as shown in graph 2.