Câu 7:
a,
$CaCO_3+2HCl\to CaCl_2+CO_2+H_2O$
$n_{CaCO_3}=\dfrac{10}{100}=0,1(mol)$
Theo PTHH:
$n_{CO_2}=n_{CaCO_3}=0,1(mol)$
$\to V_{CO_2}=0,1.22,4=2,24l$
b,
$n_{CaCl_2}=n_{CaCO_3}=0,1(mol)$
$m_{\text{dd spu}}=10+200-0,1.44=205,6g$
$\to C\%_{CaCl_2}=\dfrac{0,1.111.100}{205,6}=5,4\%$
Câu 8:
a, $Na, Ba$
$2Na+2H_2O\to 2NaOH+H_2$
$Ba+2H_2O\to Ba(OH)_2+H_2$
b, $Na, Mg, Ba, Fe, Zn$
$2Na+2HCl\to 2NaCl+H_2$
$Mg+2HCl\to MgCl_2+H_2$
$Ba+2HCl\to BaCl_2+H_2$
$Fe+2HCl\to FeCl_2+H_2$
$Zn+2HCl\to ZnCl_2+H_2$
c, $Mg, Fe, Zn$
$Mg+CuCl_2\to MgCl_2+Cu$
$Fe+CuCl_2\to FeCl_2+Cu$
$Zn+CuCl_2\to ZnCl_2+Cu$
