При сгорании безызвестного вещества массой 3,42 г образовался оксид углерода( 4)

Ответ:

дано

m(CxHyOz) = 3.42 g

m(CO2) = 5.28 g

m(H2O) = 1.98g

M(CxHyOz) = M(H2O) * 19

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CxHyOz-?

M(CO2) = 44 g/mol

n(CO2) = m(CO2) / M(CO2) = 5.28 / 44 = 0.12 mol

n(C) = n(CO2) = 0.12 mol

M(C) = 12 g/mol

m(C) = n(C)  * M(C) = 0.12 *12 = 1.44 g

M(H2O) = 18 g/mol

n(H2O) = m(H2O) / M(H2O) = 1.98 / 18 = 0.11 mol

n(H) = 2*n(H2O) = 2 * 0.11 = 0.22 mol

M(H) = 1 g/mol

m(H) = n(H) * M(H) = 0.22 * 1 = 0.22 g

m(O) = m(CxHyOz) - (m(C) + m(H)) = 3.42 - ( 1.44 + 0.22) = 1.76 g

M(O) = 16 g/mol

n(O) = m(O) / M(O) = 1.76 / 16 = 0.11 mol

n(C) : n(O) : n(H) = 0.12 : 0.11: 0.22 = 12:11 : 22

C12O11H22

M(CxHyOz) = M(H2O) * 19 = 18 * 19 = 342 g/mol

M(C12H22O11) = 342 g/mol

ответ : САХАРОЗА

Объяснение: