nr.moli.ZnSO4 = 2,5 moli
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m.H2 = ? g
V.H2 = ? L
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2,5 moli n moli
Zn + H2SO4 --> ZnSO4 + H2
1 1
=> n = 1x2,5/1 = 2,5 moli H2
M.H2 = 2x1 = 2 g/mol
nr. moli= m/M => m.H2 = mxn = 2x2,5 = 5 g H2