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Question
Which of the following weighs the least?
Options
2 g atom of N
3 x 1025 atoms of carbon
1 mole of sulphur
7 g silver
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Solution
7 g silver
Explanation:
wt. of 2 g atom of N = 2 x 14 = 28 g
wt. of 3 x 1025 atoms of carbon = `(12 xx 3 xx 10^25)/(6.022 xx 10^23)` = 597.7 g
wt. of 1 mole of sulphur= 32 g
silver = 7 g
∴ silver has the least weight.
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