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प्रश्न
Calculate the number of oxygen atoms in 0.10 mole of Na2CO3 . 10H2O.
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उत्तर
1molecule of Na2CO3 . 10H2O contains oxygen atoms = 13
So, 6.023 × 1023 molecules (1 mole) has atoms = 13 × 6.023 × 1023
So, 0.10 mole will have atoms = 0.1 × 13 × 6.02 × 1023
= 7.826 × 1023
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