Question

Cần 50g dd H2SO4 40% vào bao nhiêu ml nước để thu được dd H2SO4 10%

Answer 1

\(n_{H_2SO_4}=40\%.50=20\left(g\right)\\ Gọi:a=m_{H_2O\left(thêm\right)}\\ \Rightarrow\dfrac{20}{50+a}.100\%=10\%\\ \Leftrightarrow a=150\left(g\right)\\ \Rightarrow V_{H_2O\left(thêm\right)}=\dfrac{150}{1}=150\left(ml\right)\)

Answer 2

Answer 3

$m_{CT_{H_2SO_4}}=50.40\%=20(g)$

$m_{dd_{H_2SO_4(10\%)}}=\dfrac{20}{10\%}=200(g)$

$\to m_{H_2O\text{ thêm}}=200-50=150(g)$

$\to V_{H_2O\text{ thêm}}=\dfrac{150}{1}=150(ml)$