a) \(\left\{{}\begin{matrix}m_{HCl}=500.10\%+500.20\%=150\left(g\right)\\m_{dd}=500+500=1000\left(g\right)\end{matrix}\right.\)
`=>` \(C\%_{HCl\left(mới\right)}=\dfrac{150}{1000}.100\%=15\%\)
b) \(\left\{{}\begin{matrix}n_{HCl}=\dfrac{150}{36,5}=\dfrac{300}{73}\left(mol\right)\\V_{dd}=\dfrac{1000}{1,2}=\dfrac{2500}{3}\left(ml\right)=\dfrac{5}{6}\left(l\right)\end{matrix}\right.\)
`=>` \(C_{M\left(HCl\right)}=\dfrac{\dfrac{300}{73}}{\dfrac{5}{6}}=\dfrac{360}{73}M\)
\(\begin{array}{l}
a)\\
{m_{HCl}} = 500 \times 10\% + 500 \times 20\% = 150g\\
{m_{{\rm{dd}}}} = 500 + 500 = 1000g\\
{C_\% }HCl = \dfrac{{150}}{{1000}} \times 100\% = 15\% \\
b)\\
{V_{{\rm{dd}}HCl}} = \dfrac{{1000}}{{1,2}} = 833,33\,ml = 0,83333l\\
{n_{HCl}} = \dfrac{{150}}{{36,5}} = 4,1\,mol\\
{C_M}HCl = \dfrac{{4,1}}{{0,83333}} = 4,92M
\end{array}\)
