Дано
m(HCL) = 4.8 g
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m(Zn)-?
n(Zn)-?
Zn+2HCL --->ZnCL2+H2
M(HCL)= 36.5 g/mol
n(HCL) = m/M = 4.8 / 36.5 = 0.13 mol
n(Zn) = 2n(HCL)
n(Zn) = 0.13 / 2 = 0.065 mol
M(Zn)= 65 g/mol
m(Zn) = n*M = 0.065 * 65 = 4.225 g
ответ 4.225 г , 0.065 моль