Answers

2015-10-30T20:01:27+05:30
mass of oxygen gas (O2) = 16 * 2 = 32 grams
therefore 18 grams = 1 mole
therefore 12 grams = 12 / 32
                             = 0.375 moles 
i hope that this will help u........................^_^
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2015-10-30T20:04:40+05:30
1 mole of O2 gas is 32 grams.

No. of moles in 12 g = 12/32 which is 3/8 moles or 0.375 moles
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