1.
Mg + 2HCl -> MgCl2 + H2
nMg=0,1(mol)
Theo PTHH ta có:
nMg=nMgCl2=nH2=0,1(mol)
nHCl=2nMg=0,2(mol)
mMgCl2=95.0,1=9,5(g)
VH2=22,4.0,1=2,24(lít)
CM dd HCl=\(\dfrac{0,2}{0,5}=0,4M\)
2.
2NaOH + CuSO4 -> Cu(OH)2 + Na2SO4
nNaOH=0,2(mol)
nCuSO4=0,1(mol)
Vì 0,1.2=0,2 nên PƯ xảy ra vừa đủ
Theo PTHH ta có:
nCuSO4=nCu(OH)2=nNa2SO4=0,1(mol)
mkết tủa=98.0,1=9,8(g)
CM dd Na2SO4=\(\dfrac{0,1}{0,1}=1M\)