`#AkaShi`
PTHH:
`BaCl_2 + H_2SO_4 -> BaSO_4↓ + 2HCl`
`\text{_____________________________________________}`
`a)`
`->m_{BaCl_2}=m_{dd}xxC%=400xx5,2%=20,8 (g)`
`->n_{BaCl_2}=(m_{BaCl_2})/(M_{BaCl_2})=(20,8)/208=0,1 (mol)`
Theo tỉ lệ pt:
`->n_{H_2SO_4}=n_{BaCl_2}=0,1 (mol)`
`->m_{H_2SO_4}=n_{H_2SO_4}xxM_{H_2SO_4}=0,1xx98=9,8 (g)`
`->m_{dd}=m_{H_2SO_4}:C%=9,8:20%=49 (g)`
`\text{_____________________________________________}`
`b)`
`->n_{BaSO_4}=n_{BaCl_2}=0,1 (mol)`
`->m_{dd}=400+49-0,1xx233=425,7 (g)`
`->n_{HCl}=2xxn_{BaCl_2}=2xx0,1=0,2 (mol)`
`->C%_{HCl}=(36,5xx0,2)/(425,7)xx100%=1,17%`
`\text{_____________________________________________}`
`**` Đáp án:
`a) m_{dd\ H_2SO_4}=49 (g)`
`b) C%_{HCl}=1,71%`
