Ответ:

дано

m(C6H5OH) = 40 g

W() = 15%

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V(H2) - ?

m(C6H5OH) = 40 - (40*15% / 100%) = 34 g

2C6H5OH+2Na-->2C6H5ONa+H2

M(C6H5OH) = 94 g/mol

n(C6H5OH) = m/M = 34 / 94 = 0.36 mol

2n(C6H5OH) = n(H2)

n(H2) = 0.36 / 2 = 0.18 mol

V(H2) = n*Vm = 0.18 * 22.4 = 4.032 L

ответ 4.032 л

Объяснение: