Question

O placuta de zinc reactioneaza cu 200 g solutie de azotat de argint de concentratie 34%. Determina masa cu care creste placuta si concentratia solutiei finale.

Answer 1

$Zn+2AgNO_3=Zn(NO_3)_2+2Ag \\ m_d=200* \frac{34}{100} = \frac{6800}{100} =68gAgNO_3 \\ \frac{68}{170} =0,4moli \\ 200-68=132g-apa \\ 0,4*65=26g \\ 0,4*108=43,2 \\ 43,2-26=17,2 \\ m_d=0,2*127=25,4g \\ m_s=25,4+132=157,4g \\ c= \frac{25,4}{157,4} *100=0,1613*100=16,13$