1-15
2-23
3-42
4-24
5-35
6-42
7:
2mg+o2=2mgo
2na+2h2o=2naoh+h2
zn+2hcl=zncl2+h2
4as+3o2=2as2o3
6li+n2=2li3n
al2s3+6k=3k2s+2al
1-15
2-23
3-42
4-24
5-35
6-42
7:
2mg+o2=2mgo
2na+2h2o=2naoh+h2
zn+2hcl=zncl2+h2
4as+3o2=2as2o3
6li+n2=2li3n
al2s3+6k=3k2s+2al