Question

A mixture of hydrogen and oxygen is ignited and reacts completely to form water. Which mixture will NOT produce 18 g of H2O?

(A)2.0 g H2, 16.0 g O2

(B)2.0 g H2, 18.0 g O2

(C)4.0 g H2, 16.0 g O2

(D)4.0 g H2, 18.0 g O2

Answer 1

H2 +1/2O2 --> H2O
1 mol H2 react with 1/2 mole O2 to give 1 mole H2O
So according to balanced equation
2 g[=1 mole] H2 react with 16 g [=1/2 mol O2] to gib=ve 18 g[=1 =mole]
H2O

(A)2.0 g H2, 16.0 g O2 will produce exactly 18 g H2O ;by consuming both reactants
completely

B)2.0 g H2, 18.0 g O2 will produce exactly 18 g of H2O by consuming
2 g H2 completely

c) C)4.0 g H2, 16.0 g O2 will produce exactly 18 g of H2O by consuming
16 g O2 completely.

D)4.0 g H2, 18.0 g O2 will produce more than 18 g of H2O . SInce both reactants
are in excess quantity mass of H2O will be more than 18 g

Hence answer is option D
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