I the HCI is the mass of the equation but not always answer is Mg+HC H20
I'm going to go with Physical.
Through hypothesis and experiments
Answer:4
Explanation:To balance the equation you need to make the number of each element equivalent in both sides.
To start add a 2 in front of the MnO2 which balances the Mn.
Then balance the oxygen by adding a 4 in front of H20.
The H then needs a 8 as it’s coefficient.
