Add 4H2 in the reactant side, that will give you 4H2O in the product side.
Explanation:
I
have not yet learnt chemistry so sorry
In an experiement things that are changing are called variables.
Answer:
a number assigned to an element in chemical combination which represents the number of electrons lost (or gained, if the number is negative), by an atom of that element in the compound
Explanation:
sodium, magnesium, iron is zero.
