* $7,2g$ $Mg$
a,
$n_{Mg}=\dfrac{7,2}{24}=0,3(mol)$
$2CH_3COOH+Mg\to (CH_3COO)_2Mg+H_2$
$n_{H_2}=n_{Mg}=0,3(mol)$
$\to V_{H_2}=6,72l$
b,
$n_{(CH_3COO)_2Mg}=n_{Mg}=0,3(mol)$
$\to m_{\rm muối}=42,6g$
c,
$n_{CH_3COOH}=2n_{Mg}=0,6(mol)$
$\to m=0,6.60:10\%=360g$
$\to m_{\text{dd spu}}=360+7,2-0,3.2=366,6g$
$\to C\%_{(CH_3COO)_2Mg}=\dfrac{42,6.100}{366,6}=11,62\%$
d,
$H=70\%\to n_{CH_3COOC_2H_5}=0,6.70\%=0,42(mol)$
$\to m_{CH_3COOC_2H_5}=0,42.88=36,96g$
* $5,4g$ $Al$
a,
$n_{Al}=\dfrac{5,4}{27}=0,2(mol)$
$6CH_3COOH+2Al\to 2(CH_3COO)_3Al+3H_2$
$\to n_{H_2}=1,5n_{Al}=0,3(mol)$
$\to V_{H_2}=6,72l$
b,
$n_{(CH_3COO)_3Al}=n_{Al}=0,2(mol)$
$\to m_{\rm muối}=40,8g$
c,
$n_{CH_3COOH}=3n_{Al }=0,6(mol)$
$\to m=0,6.60:10\%=360g$
$\to m_{\text{dd spu}}=360+5,4-0,3.2=364,8g$
$\to C\%_{(CH_3COO)_3Al}=\dfrac{40,8.100}{364,8}=11,18\%$
d,
$H=70\%\to n_{CH_3COOC_2H_5}=0,6.70\%=0,42(mol)$
$\to m_{CH_3COOC_2H_5}=0,42.88=36,96g$
* $13g$ $Zn$
a,
$n_{Zn }=\dfrac{13}{65 }=0,2(mol)$
$2CH_3COOH+Zn \to (CH_3COO)_2Zn+H_2$
$n_{H_2}=n_{Mg}=0,2(mol)$
$\to V_{H_2}=4,48l$
b,
$n_{(CH_3COO)_2Zn}=n_{Zn }=0,2(mol)$
$\to m_{\rm muối}=36,6g$
c,
$n_{CH_3COOH}=2n_{Zn }=0,4(mol)$
$\to m=0,4.60:10\%=240g $
$\to m_{\text{dd spu}}=240+13 -0,2.2=252,6g$
$\to C\%_{(CH_3COO)_2Zn}=\dfrac{36,6.100}{252,6}=14,49\%$
d,
$H=70\%\to n_{CH_3COOC_2H_5}=0,4.70\%=0,28 (mol)$
$\to m_{CH_3COOC_2H_5}=0,28 .88=24,64g$