Question

What change could you make to properly balance the chemical equation?

2 + 02 → 2H₂O
Add a coefficient of 2 in front of H₂
Remove the 2 from in front of H₂O
Add a subscript of 2 to Na
Change the subscript on H from 2 to 4

Answer 1

Add a coefficient of 2 in front of
`H_2`

Step-by-step explanation:

To rule out the rest of the options:

You can't remove the 2 from in front of H2O because you would still have two oxygen atoms. (You can't change a subscript; it's the formula of the compound.)

There's no sodium...?

Again, can't change a subscript because it would change the compound's identity.

So adding 2 in front of
`H_2` would balance the equation.

2 moles of hydrogen gas (2 moles times 2 atoms) + 1 mole oxygen gas (2 atoms) = 2 moles of water (each contains two hydrogen atoms and one oxygen)

Hope that helps :)