Ответ:
дано
m(ppa H2SO4) = 100 g
W(H2SO4) = 4.9%
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m(Al2(SO4)3)-?
m(H2SO4) = 100 * 4.9 / 100% = 4.9 g
M(H2SO4) = 98 g/mol
n(H2SO4) = m/M = 4.9 / 98 = 0.05 mol
3H2SO4 + 2Al(OH)3-->Al2(SO4)3+6H2O
n(Al2(SO4)3) = 0.05 * 1 / 3= 0.017 mol
M(Al2(SO4)3) = 342 g/mol
m(Al2(SO4)3) = n*M = 0.017 * 342 = 5.814 g
ответ 5.814 г
Объяснение: