Đáp án:
a/ $V≈0,866\ lít$
b/ $C\%=70,22\%$
Giải thích các bước giải:
Khí sinh ra mùi trứng thối ⇒ là $H_2S$
$8Fe(OH)_2+13H_2SO_4\to 4Fe_2(SO_4)_3+H_2S↑+20H_2O$
$n_{Fe(OH)_2}=\dfrac{18}{90}=0,2\ mol$
a/ Theo PTHH
$n_{H_2S}=\dfrac{1}{8}.n_{Fe(OH)_2}=0,025\ mol$
$540 mmHg = \dfrac{540}{760}atm =\dfrac{27}{38}atm$
$⇒V=\dfrac{n.R.T}{P}\\⇔V=\dfrac{0,025.0,082.(27+273)}{\dfrac{27}{38}}≈0,866\ lít$
b/ Theo PTHH:
$n_{H_2SO_4}=\dfrac{13}{8}.n_{Fe(OH)_2}=0,325\ mol\\⇒m_{H_2SO_4}=0,325.98=31,85g\\⇒m_{dd\ H_2SO_4}=39,8125g$
$⇒m_X=18+39,8125-0,025.34=56,9625g$
$n_{Fe_2(SO_4)_3}=0,5.0,2=0,1\ mol\\⇒m_{Fe_2(SO_4)_3}=40g\\⇒C\%=\dfrac{40}{56,9625}.100\%=70,22\%$
