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Question
How many moles are there in 34.5 g of sodium ? (Atomic mass of Na = 23 u)
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Solution
Mass of zinc = 10g
gram atomic mass of zinc = 65g
We know that one mole of zinc contains 6.022 × 1023 atoms of zinc.
65g of zinc contain = 6.022 × 1023 atoms
Therefore, 10g of zinc contain = 10 × 6.022 × 1023/65 = 9.264 × 1022 atoms
Hence, 10 grams of zinc contain 9.264 × 1022 atoms.
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