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Question
Four grams of caustic soda contains ______.
Options
6.02 x 1023 atoms of it
4 g atom of sodium
6.02 x 1022 molecules
4 moles of NaOH
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Solution
Four grams of caustic soda contains 6.02 x 1022 molecules.
Explanation:
40 g of NaOH contains 6.023 x 1023 molecules
So, 4 g of NaOH contains = `4/40 xx 6.02 xx 10^23`
= `1/10 xx 6.02 xx 10^23`
= 6.02 x 1022 molecules
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