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Question
Each of the two flasks contains 2.0 g of gas at the same temperature and pressure. One flask contains oxygen and the other hydrogen. Which sample contains the greater number of molecules?
Solution
Flask having oxygen gas :
16g of oxygen gas has = 6.023 x 1023 molecules.
2g of oxygen gas will have = 6.023 x 1023/16 x 2 = 0.75 x 1023
Flask having hydrogen :
1g of hydrogen has= 6.023 x 1023 molecules.
2g of hydrogen gas will have = 6.023 x 1023 x 2/1 = 12.05 x 1023
So, hydrogen gas has greater number of molecules.
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