Can anyone balance these for me please :)? It's due today but I don't understand these.

1. MgCl2(aq) + H2SO4(aq) = Mg(SO4)2(aq) + 2HCl(aq)
2. Sr(s) + F2(g) = Sr2F
3. 2NaHCO3(s) + 2HCl(aq) = 2NaCl(s) + 2CO2(g)
4. 2LiOH(aq) + 2HBr(aq) = 2LiBr(aq) + 2H2O
5. 2Ca(s) + Cl2(g) = 2CaCl(aq)
5. NH4OH(aq) + KOH(aq) = KOH(aq) + NH4OH(aq)

1. MgCl2(aq) + H2SO4(aq) --> Mg(SO4)(aq) + 2HCl(aq)

2. Sr(s) + F2(g) = SrF2

3. 2NaHCO3(s) + 2HCl(aq) = 2NaCl(s) + 2CO2(g) + 2H2O

4. 2LiOH(aq) + 2HBr(aq) = 2LiBr(aq) + 2H2O

5.  2Ca(s) + 2Cl2(g) = 2CaCl2(s)

6. NH4OH(aq) + KOH(aq) = KOH(aq) + NH4OH(aq)

Explanation:

1. Its MgSO4 not Mg(SO4)2.

2. SrF2 not Sr2F.

3. 2H2O was missed out.

4.  It's CaCl2 not CaCl.

The count of each element must be the same for each side of the equation.

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.