ile g NaCl potrzeba do prygotowania 500g 8% roztworu ?

Cp=8% mr=500g ms=Cp*mr/100% ms=8*500/100 ms = 40g NaCl

[latex]m_r = 500g\ C_p = 8\%\ m_s = ?\ \ C_p = frac{m_s cdot 100\%}{m_r} | cdot m_r\ C_p cdot m_r = m_s cdot 100\% | :100\%\ frac{C_p cdot m_r}{100\%} = m_s\ m_s = frac{8\% cdot 500g}{100\%} = 40g\ \ Odp.: Do przygotowania roztworu nalezy uzyc 40g NaCl.[/latex]