a)\(n_{MgO}\)=6:40=0,15(mol)

Ta có PTHH:

MgO+\(H_2SO_4\)->MgS\(O_4\)+\(H_2O\)

0,15......0,15...........0,15..................(mol)

Theo PTHH:\(m_{H_2SO_4}\)=0,15.98=14,7g

b)Ta có:\(m_{ddH_2SO_4}\)=D.V=1,2.50=60(g)

=>Nồng độ % dd \(H_2SO_4\) là:

\(C_{\%ddH_2SO_4}\)=\(\dfrac{14,7}{60}\).100%=24,5%

c)Theo PTHH:\(m_{MgSO_4}\)=0,15.120=18(g)

Khối lượng dd sau pư là:

\(m_{ddsau}\)=\(m_{MgO}\)+\(m_{ddH_2SO_4}\)=6+60=66(g)

Vậy nồng độ % dd sau pư là:

\(C_{\%ddsau}\)=\(\dfrac{18}{66}\).100%=27,27%

a)nMgO=6:40=0,15(mol)

Ta có PTHH:

MgO+->MgS

0,15......0,15...........0,15..................(mol)

Theo PTHH:mH2SO4=0,15.98=14,7g

b)Ta có:mddH2SO4=D.V=1,2.50=60(g)

=>Nồng độ % dd  là:

C%ddH2SO418\66.100%=27,27%

a)nMgO=0,15(mol)

Ta có PTHH:

MgO+H2SO4->MgSO4+H2O

0,15......0,15...........0,15..................(mol)

Theo PTHH:mH2SO4=0,15.98=14,7g

b)Ta có:mddH2SO4=1,2.50=60(g)

=>Nồng độ % dd H2SO4là:

C%ddH2SO4=\(\dfrac{14,7}{60}100\)=24,5%

c)Theo PTHH:mMgSO4=0,15.120=18(g)

Khối lượng dd sau pư là:

mddsau=6+60=66(g)

Vậy nồng độ % dd sau pư là:

C%ddsau=\(\dfrac{18}{66}.100\)=27,27%

a) \(n_{MgO}=\frac{6}{40}=0,15mol\)

PTHH : \(MgO+H_2SO_4\rightarrow MgSO_4+H_2O\)

Theo PTHH: \(n_{H_2SO_4}=n_{MgO}=0,15mol\)

=> \(m_{H_2SO_4}=0,15.98=14,7g\)

b) \(m_{dd}=1,2.50=60g\)

\(C\%=\frac{14,7.100}{60}=24,5\%\)

c)Theo PTHH : \(n_{MgSO_4}=n_{MgO}=0,15mol\Rightarrow m_{MgSO_4}=0,15.120=18g\)

\(m\)dd sau p/ứng = 6 +60 = 66 g

C% sau p/ứng = \(\frac{18.100}{66}=27,\left(27\right)\%\)

\(n_{MgO}=\frac{m}{M}=\frac{6}{40}=0,15\left(mol\right)\)

\(PTHH:MgO+H_2SO_4\rightarrow MgSO_4+H_2O\)

(mol) 1 1 1 1

(mol) 0,15 0,15 0,15 0,15

\(a.m_{H_2SO_4}=n.M=0,15.98=14,7\left(g\right)\)

\(b.m_{ddH_2SO_4}=D.V=50.1,2=60\left(g\right)\)

\(\rightarrow C\%_{ddH_2SO_4}=\frac{m_{ct}}{m_{dd}}.100\%=\frac{14,7}{60}.100\%=24,5\left(\%\right)\)

\(c.m_{ddspu}=m_{MgO}+m_{ddH_2SO_4}=6+60=66\left(g\right)\)

\(C\%_{ddM}=\frac{120,0,15}{66}.100\%=27,27\left(\%\right)\)

\(a,n_{H_2SO_4}=1.0,1=0,1(mol)\\ PTHH:2NaOH+H_2SO_4\to Na_2SO_4+2H_2O\\ \Rightarrow n_{naOH}=2n_{H_2SO_4}=0,2(mol)\\ \Rightarrow m_{dd_{NaOH}}=\dfrac{0,2.40}{10\%}=80(g)\\ b,m_{dd_{H_2SO_4}}=1,2.100=120(g)\\ n_{Na_2SO_4}=0,1(mol)\\ \Rightarrow C\%_{Na_2SO_4}=\dfrac{0,1.142}{80+120}.100\%=7,1\%\)

Bài 2

Ta có:

nFe=0,2 mol nHCl=0,6 mol
Fe+2HCl=FeCl2+H2
0,2->0,4--->0,2
suy ra sau phản ứng có: 0,2molFeCl2 và 0,2mol HCl dư
C_M muối=0,2/0,2=1M
C_M axit dư=0,2/0,2=1M

BÀi 1

pt 2NAOH+H2SO4--->NA2SO4+2H20

nH2SO4=0,2*0,2=0,04 mol suy ra vH2SO4=22,4*0,04=0,896L

mNAOH=4*200:100=8g suy ra n NAOH=0,2 mol

mdd sau pứ=510+8=518

theo pt thì NAOH DƯ

theo pt mNA2SO4=5,68 g suy ra C%NA2SO4=5,68:518*100=2%

Đây là hóa mấy x bạn

Ta có: \(n_{H_2}=\dfrac{6,72}{22,4}=0,3\left(mol\right)\)

a. PTHH: \(Zn+H_2SO_4--->ZnSO_4+H_2\uparrow\left(1\right)\)

b. Theo PT₍₁₎: \(n_{Zn}=n_{H_2}=0,3\left(mol\right)\)

\(\Rightarrow m_{Zn}=65.0,3=19,5\left(g\right)\)

c. Theo PT₍₁₎: \(n_{H_2SO_4}=n_{Zn}=0,3\left(mol\right)\)

Đổi 300ml = 0,3 lít

\(\Rightarrow C_{M_{H_2SO_4}}=\dfrac{0,3}{0,3}=1M\)

d. PTHH: \(2NaOH+H_2SO_4--->Na_2SO_4+2H_2O\left(2\right)\)

Theo PT₍₂₎: \(n_{NaOH}=2.n_{H_2SO_4}=2.0,3=0,6\left(mol\right)\)

\(\Rightarrow m_{NaOH}=0,6.40=24\left(g\right)\)

\(\Rightarrow m_{dd_{NaOH}}=\dfrac{24.100\%}{20\%}=120\left(g\right)\)