\(\frac{{{\text{Weight}}{\mkern 1mu} {\mkern 1mu} \,{\text{of}}{\mkern 1mu} {\mkern 1mu} \,Cu}}{{0.50}} = \frac{{63.6/2}}{1}\)
\({\text{Weight}}{\mkern 1mu} {\mkern 1mu} {\text{of}}{\mkern 1mu} {\mkern 1mu} Cu = 15.9{\mkern 1mu} \,gm\)
(નજીકનાં પૂર્ણાંકમાં રાઉન્ડ ઑફ). $\left[\right.$ આપેલ $, E_{C u^{2+} / C u}^{o}=0.34\, V , E _{ NO _{3}^{-} / NO_2 }^{\circ}=0.96\, V$ $,E _{ NO _{3} / NO _{2}}^{\circ}=0.79 \,V$ $\left.\frac{ RT }{ F }(2.303)=0.059\right]$
$H_3PO_4 + OH^- \rightarrow H_2PO_4^- + H_2O$ ;
$H_3PO_4 + 2OH^- \rightarrow HPO_4^{2-} + 2H_2O$ ;
$H_3PO_4 + 3OH^- \rightarrow PO_4^{3-} + 3H_2O$