Answer:
Explanation:
2 NH4I Â Â + Pb(NO3)2 Â = Â PbI2 Â + 2 NH4NO3
2 mol      1 mol
x ml       751 ml
0.550 M Â Â Â 0.380 M
0.380 mol/1000 ml  x 751 ml =  0.285 mol Pb(NO3)2
0.285 mol Pb(NO3)2 x 2 mol NH4I/1 mol  Pb(NO3)2=0.571 mol  NH4I  needed
0.571 mol  NH4I/0.550 mol/1000 ml=1038 ml