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प्रश्न
A sample of vitamic C is known to contain 2.58 ×1024 oxygen atoms. How many moles of oxygen atoms are present in the sample?
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उत्तर
Number of oxygen atoms in the sample = 2.58 x 1024
= 2.58 × 1024
6.022 × 1023 atoms of oxygen = 1 mole
2.58 × 1024 atoms of oxygen = `(2.58 xx 10^24)/(6.022 xx 10^23)` moles
= 4.28 moles
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