I have posted the answetr in this picture.
The correct answer is option 2. When Pt2+ is reduced it loses electrons, oxidizing it. The oxidation number is the charge of the atom. Adding an electron, decreases the net charge consequently the oxidation number.
The relation between rate constants at different temperatures, temperature and activation energy is known as Arrhenius equation
<u>Arrhenius equation</u>

For two temperatures

Where
Ea = ? = activation energy
k1 = 3.36 × 10⁴
T1=344 k
k2=7.69
T2=219K
R= gas constant = 8.314 J /molK
Putting values

Ea = (-69.69)/(-0.00166) = 41981.93 J/mol
Or
Activation energy is 42.0 kJ /mol
Answer:
The emmision of ionizing radiation or particles caused by the spontaneous disintegration of atomic nuclei
or
the giving off of rays of energy or particles by the breaking apart of atoms of certain elements