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Question
Solve problem:
Calculate the number of atoms of the following. (Average atomic mass : N = 14 u, S = 32 u)
0.4 mole of nitrogen
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Solution
0.4 mole of nitrogen (N)
Number of atoms of N = Number of moles × Avogadro's constant
= 0.4 mol × 6.022 × 1023 atoms/mol
= 2.4088 × 1023 atoms of N
Number of nitrogen atoms in 0.4 mole = 2.4088 × 1023 atoms of N
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