дано
m(Ca) = 180 g
m(CaOH)2-?
Ca+2HOH-->Ca(OH)2+H2
M(Ca) = 40g/mol
n(Ca) = m/M = 180 / 40 = 4.5 mol
n(Ca) = n(Ca(OH)2) = 4.5 mol
M(Ca(OH)2) = 74 g/mol
m(Ca(OH)2) = n*M = 4.5 * 74 = 333g
ответ 333 г
