Răspuns:
a)
2Mg + O2=> 2 MgO
2 Ba + O2 => 2 BaO
b) MMg=24g/mol
MMgO=24+16=40g/mol
MBa =137g/mol
MBaO =137+16=153g/mol
mMg=1×24=g
mBa=1×137=137g
2×24g 2×40g
2Mg + O2=> 2 MgO
24g xg
x=24×2×40/2×24=40gMgO
2×137g 2×153g
2 Ba + O2 => 2 BaO
137g yg
y=137×2×153/2×137=153g BaO