(4) chemical energy to electrical energy is the correct answer.
Hope this helps~
Well it's an alkali metal if that's what you're asking<span />
Explanation:
Charles' law gives the relationship between the volume and the temperature of the gas. Mathematically,
Volume ∝ Temperature
i.e. 
We have, V₁ = 1.6 L, T₁ = 278 K, T₂ = 253, V₂=?

So, the new volume is 1.45 L.
Answer:
It will have 5 valence electrons as its in group 5.
The atom will gain as its closer to the full configuration 8.
The charge will be 3- as it will gain 3 electrons.