Lời giải chi tiết `:`
Bài `1:`
$a/$
`m_{dd}=m_{Zn(NO_3)_2}+m_{H_2O}=18,9+281,1=300(g)`
`->` `%_{Zn(No_3)_2}={18,9}/300 .100%=0,063.100%=6,3%`
$b/$
`C%_{AgNo_3}={m_{AgNO_3}}/{m_{dd}}=34/200 .100%=0,17.100%=17%`
`----------`
Bài `2:`
$a/$
`m_{dd CuSO_4}={mct.100}/C={8.100}/10=800/10=80(g)`
$b/$
`m_{dd BaCl_2}={mct.100}/C={16.100}/20=1600/20=80(g)`
`----------`
Bài `3:`
$a/$
`200` gam dung dịch `H_2SO_4` `9,8%`
`->` `m_{H_2SO_4} = { 200. 9,8}/ 100=1960/100=19,6 (g)`
`->` `n_{H_2SO_4} = {19,6}/98=0,2 (mol)`
$b/$
`150` gam dung dịch `Fe_2(SO_4)_3` `20%`
`->` `m_{Fe_2(SO_4)_3}=(150.20)/100=30(g)`
`->` `n_{Fe_2(SO_4)_3}=30/400=0,075(mol)`
$c/$
`300` gam dung dịch `NaOH` `10%`
`->` `m_{NaOH}=(300.10)/100=3000/100=30(g)`
`->` `n_{NaOH}=30/40=0,75(mol)`
$d/$
`400` gam dung dịch `MgCl_2` `9,5 %`
`->` `m_(MgCl_2)=(400.9,5)/100=3800/100=38(g)`
`->` `n_(MgCI_2)= 38/95=0,4(mol)`
`----------`
Bài `4:`
$a/$
`n_(KOH)={11,2}/(56)=0,2(mol)`
`C_(M_(KOH))=(0,2)/2=0,1M`
$b/$
`n_(AICI_3)=(2,67)/(133,5)=0,02(mol)`
`C_(m_(AICI_3))=(0,02)/(0,1)=0,2M`
`----------`
Bài `5:`
$a/$
`n_{Ca(OH)_2}=(14,8)/74=0,2(mol)`
`V_{Ca(OH)_2}=(0,2)/(0,2)=1l`
$b/$
`n_{pb(NO_3)_2}=(6,62)/331=0,02(mol)`
`V_{pb(NO_3)_2}=(0,02)/(0,1)=0,2l=200ml`