Răspuns:
MCa3(PO4)2=3×40+2×31+8×16=310g/mol
m=0,3×310=93g
MCa(OH)2=40+2×16+2×1=74g/mol
3×74g 310g
3Ca(OH)2+ 2H3PO4 => Ca3(PO4)2+6H2O
xg 93g
x=93×3×74/310= calculează