# Question #3d976

Dec 7, 2016

$2 C a \left(s\right) + {O}_{2} \left(g\right) \implies 2 C a O \left(s\right)$

#### Explanation:

I'm going to assume that this is the chemical system:

$2 C a \left(s\right) + {O}_{2} \left(g\right) \implies 2 C a O$

and then the reaction can be shown by simply balancing the chemical equation.

The equation is both mass and charge balanced. No notation to show a charge is needed.

Because you mention charge, I will go over the oxidation state.

The oxidation state for $C a$ and ${O}_{2}$ are $0 +$

In the species $C a {O}_{2}$:

$C a$ has an oxidation state of $2 +$
$O$ has an oxidation state of $2 -$.

Calcium is oxidized and oxygen is reduced .