Trộn 50ml dd HCL 0.1M với 250ml dd HCL 0.2M .Tính nồng độ mol cỉa các ion .
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(n_{H_2SO_4}=0,05.0,4=0,02\left(mol\right)\\ n_{HCl}=0,35.0,2=0,07\left(mol\right)\\ \left[H_2SO_4\right]=\dfrac{0,02}{0,05+0,35}=0,05\left(M\right)\\ \left[HCl\right]=\dfrac{0,07}{0,05+0,35}=0,175\left(M\right)\\ \Rightarrow\left[H^+\right]=0,05.2+0,175.1=0,275\left(M\right)\\ \left[SO^{2-}_4\right]=0,05\left(M\right)\\ \left[Cl^-\right]=0,175\left(M\right)\)
\(n_{HCl\left(0,2M\right)}=0,25.0,2=0,05\left(mol\right)\)
\(n_{HCl}\left(0,4M\right)=0,35.0,4=0,14\left(MOL\right)\)
\(C_{M\left(ddthudc\right)}=\dfrac{0,05+0,14}{0,25+0,35}=0,31667\left(M\right)\)
\(n_{HCl.5M}=0,05\times5=0,25\left(mol\right)\)
\(m_{ddHCl.30\%}=200\times1,33=266\left(g\right)\)
\(\Rightarrow m_{HCl.30\%}=266\times30\%=79,8\left(g\right)\)
\(\Rightarrow n_{HCl.30\%}=\frac{79,8}{36,5}=\frac{798}{365}\left(mol\right)\)
\(\Rightarrow\Sigma n_{HCl}mới=0,25+\frac{798}{365}=\frac{3557}{1460}\left(mol\right)\)
\(\Sigma V_{ddHCl}mới=50+200=250\left(ml\right)=0,25\left(l\right)\)
\(\Rightarrow C_{M_{HCl}}mới=\frac{3557}{1460}\div0,25=9,75\left(M\right)\)
\(n_{HCl}=\dfrac{7,3}{36,5}=0,2\left(mol\right)\\ n_{H_2SO_4}=\dfrac{9,8}{98}=0,1\left(mol\right)\\ \left[HCl\right]=\dfrac{0,2}{0,2}=1\left(M\right)\\ \left[H_2SO_4\right]=\dfrac{0,1}{0,2}=0,5\left(M\right)\\ \left[SO_4^{2-}\right]=\left[H_2SO_4\right]=0,5\left(M\right)\\ \left[Cl^-\right]=\left[HCl\right]=1\left(M\right)\\ \left[H^+\right]=1+0,5.2=2\left(M\right)\)
Tổng số mol [H+] trong 2 axit :
nH+= 0.2(0.1+0.1*2)=0.06 (nhớ chứ ý H2SO4)
nOH-=0.02
H+ + OH- => H2O
0.06 0.02
=> nH+ dư = 0.04 => [H+]=0.1 =>pH=1
a, \(n_{H^+}=n_{Cl^-}=n_{HCl}=0,003\left(mol\right)\)
\(\Rightarrow\left[H^+\right]=\left[Cl^-\right]=\dfrac{0,003}{0,1}=0,03M\)
b, \(n_{H^+}=2n_{H_2SO_4}=0,05\left(mol\right)\Rightarrow\left[H^+\right]=\dfrac{0,05}{0,05}=1M\)
\(n_{SO_4^{2-}}=n_{H_2SO_4}=0,025\left(mol\right)\Rightarrow\left[SO_4^{2-}\right]=\dfrac{0,025}{0,05}=0,5M\)
\(n_{H^+\left(1\right)}=n_{Cl^-\left(1\right)}=0,1.0,05=0,005\left(mol\right)\)
\(n_{H^+\left(2\right)}=n_{Cl^-\left(2\right)}=0,2.0,25=0,05\left(mol\right)\)
\(\Rightarrow n_{H^+}=n_{Cl^-}=0,055\left(mol\right)\)