Answers

2014-11-01T11:16:00+05:30
1.2Mg+O2--->2MgO=
2.2HgO--->2Hg+O2=
3.2Na+2H2O--->2NAOH+H2=
4.N2+3H2--->2NH3=

5.Fe+O2--->Fe+H20=  WRONG  4 Fe + 3 O2 = 2 Fe2O3
0
2014-11-01T11:26:52+05:30
1.2Mg + O2--->2MgO (magnesium oxide)

2.2HgO--->2Hg+O2

3.2Na+2H2O--->2NAOH(sodium hydroxide) +H2( hydrogen gas)

4.3N2+3H2--->2NH3 ( Ammonia )

5.Fe+O2--->Fe+H20 [ it is wrong equation]
it should be
4Fe+3O2⇒2 Fe2O3 (ferrous oxide) 
1 5 1
u forgot smth at the first one
2Mg in -> Mg out. it should be 2. the same fot oxygen
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