câu 1: 6.10²¹ phân tử Cl2

C2H2+2Br2->C2H2Br4

x-----------2x

C2H4+Br2->C2H4Br2

y-----------2y

n Br2=0,8 mol

\(\left\{{}\begin{matrix}x+y=0,6\\2x+y=0,8\end{matrix}\right.\)

=>x=0,2 ,y=0,4 mol

=>%VC2H2=\(\dfrac{0,2.22,4}{13,44}100\)=33,33%

=>%C2H4=66,67%

C2H4+3O2-tO>2CO2+2H2O

C2H2+5\2O2-to>2CO2+H2O

=>Vkk=1,7.22,4.5=190,4l

\(n_{hh}=\dfrac{13,44}{22,4}=0,6mol\)

\(n_{Br_2}=0,4\cdot2=0,8mol\)

\(C_2H_4+Br_2\rightarrow C_2H_4Br_2\)

x             x            x

\(C_2H_2+2Br_2\rightarrow C_2H_2Br_4\)

y             2y            y

\(\Rightarrow\left\{{}\begin{matrix}x+y=0,6\\x+2y=0,8\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=0,4\\y=0,2\end{matrix}\right.\)

a)\(\%V_{C_2H_4}=\dfrac{0,4}{0,4+0,2}\cdot100\%=66,67\%\)

   \(\%V_{C_2H_2}=100\%-66,67\%=33,33\%\)

b)\(C_2H_4+3O_2\underrightarrow{t^o}2CO_2+2H_2O\)

   \(C_2H_2+\dfrac{5}{2}O_2\underrightarrow{t^o}2CO_2+H_2O\)

   \(\Rightarrow n_{O_2}=3n_{C_2H_4}+\dfrac{5}{2}n_{C_2H_2}=3\cdot0,4+\dfrac{5}{2}\cdot0,2=1,7mol\)

  \(\Rightarrow V_{O_2}=1,7\cdot22,4=38,08l\)

  \(\Rightarrow V_{kk}=5V_{O_2}=5\cdot38,08=190,4l\)

\(BTe:\)

\(3n_{Fe}=3n_{NO}\Rightarrow n_{Fe}=n_{NO}=0.01\left(mol\right)\)

\(m_{Fe}=0.01\cdot56=0.56\left(g\right)\)

Câu 1:

\(n_{CO_2}=\dfrac{11,2}{22,4}=0,5(mol)\\ a,PTHH:CO_2+Ba(OH)_2\to BaCO_3\downarrow+H_2O\\ \Rightarrow n_{Ba(OH)_2}=n_{BaCO_3}=n_{CO_2}=0,5(mol)\\ \Rightarrow C_{M_{Ba(OH)_2}}=\dfrac{0,5}{0,2}=2,5M\\ m_{BaCO_3}=0,5.197=98,5(g)\\ b,PTHH:Ba(OH)_2+2HCl\to BaCL_2+2H_2O\\ \Rightarrow n_{HCl}=2n_{Ba(OH)_2}=1(mol)\\ \Rightarrow m_{CT_{HCl}}=1.36,5=36,5(g)\\ \Rightarrow m_{dd_{HCl}}=\dfrac{36,5}{20\%}=182,5(g)\)

Câu 2:

\(n_{Fe_2O_3}=\dfrac{32}{160}=0,2(mol)\\ m_{HCl}=\dfrac{292.20\%}{100\%}=58,4(g)\\ \Rightarrow n_{HCl}=\dfrac{58,4}{36,5}=1,6(mol)\\ PTHH:Fe_2O_3+6HCl\to 2FeCl_3+3H_2O\)

Vì \(\dfrac{n_{HCl}}{6}>\dfrac{n_{Fe_2O_3}}{1}\) nên \(HCl\) dư

\(\Rightarrow n_{FeCl_3}=2n_{Fe_2O_3}=0,4(mol);n_{H_2O}=3n_{Fe_3O_3}=0,6(mol)\\ \Rightarrow \begin{cases} m_{CT_{FeCl_3}}=0,4.162,5=65(g)\\ m_{H_2O}=0,6.18=10,8(g) \end{cases}\\ \Rightarrow m_{dd_{FeCl_3}}=32+292-10,8=313,2(g)\\ \Rightarrow C\%_{FeCl_3}=\dfrac{65}{313,2}.100\%\approx20,75\%\)

\(n_{C_2H_4}=\dfrac{3,36}{22,4}=0,15\left(mol\right)\)

\(n_{Br_2}=0,4.0,5=0,2\left(mol\right)\)

PT: \(C_2H_4+Br_2\rightarrow C_2H_4Br_2\)

Xét tỉ lệ: \(\dfrac{0,15}{1}< \dfrac{0,2}{1}\), ta được Br₂ dư.

→ Dd Brom nhạt màu dần.

viết quá trình oxh khử e:

tổng số mol e cho bằng tổng số mol e nhận

=>1,2n=0,1M

=>M=24(Mg)

2N+5 + 10e -----> N2 +0

__<-----------<--0,1-------0,01

M----->M+x + xe

1,2/M----->__----->1,2x/M

=>x/M =0,1/1,2

x/M =1/12

=> M là Mg

Mg

bảo toàn e là ra đó

Gọi n là hóa trị cao nhất của M

n\(_{N_2}\) =\(\frac{n}{M}=\frac{0,224}{22,4}=0,01\) (mol)

10M+12HNO\(_3\) \(\rightarrow\) 10M(NO\(_3\))\(_n\)+ nN\(_2\)\(\uparrow\)+6H\(_2\)O

Mol \(\frac{0,1}{n}\) 0,01

\(M=\frac{m}{n}=\frac{1,2}{\frac{0,1}{n}}=\frac{1,2n}{0,1}\)

Biện luận:

n=1 => M=12 (Loại)

n=2=> M=24 (Nhận)

n=3=> M=36 (Loại)

Vậy M là Mg

5Mg+12HNO\(_3\) \(\rightarrow\) \(5Mg\left(NO_3\right)_2+N_2\uparrow+6H_2O\)