Question

tính số ml dd NaOH 2,5 % D=1,03g ml điều chế đc từ 8ml dd NaOH 35% D=1,38g ml (tính theo C% giúp em ạ)

Answer 1

\(m_{dd.NaOH.35\%}=8.1,38=11,04\left(g\right)\)

=> \(m_{NaOH\left(dd.NaOH.35\%\right)}=\dfrac{11,04.35}{100}=3,864\left(g\right)\)

=> \(m_{NaOH\left(dd.NaOH.2,5\%\right)}=3,864\left(g\right)\)

=> \(m_{dd.NaOH.2,5\%}=\dfrac{3,864.100}{2,5}=154,56\left(g\right)\)

=> \(V_{dd.NaOH.2,5\%}=\dfrac{154,56}{1,03}=150,058\left(ml\right)\)

Answer 2

\(m_{\text{dd NaOH 35%}}=8\cdot1,38=11,04\left(g\right)\\ m_{NaOH}=\dfrac{11,04\cdot35}{100}=3,864\left(g\right)\\ m_{\text{dd NaOH 2,5%}}=\dfrac{3,864\cdot100}{2,5}=154,56\left(g\right)\\ V_{\text{dd NaOH 2,5%}}=\dfrac{154,56}{1,03}\approx150\left(ml\right)\)