Question

How many atoms of copper in 3. 11 g of copper

Answer 1

• Atomic weight of copper = 63.5 g
• 1 mole of copper contains = 63.5g = 6.023 × 10²³ atoms of copper
• 1 g of copper contains
• $= \frac{ 6.023 \times 10²³}{63.5}$= 9.4 × 10²¹ atoms
• Therefore, 3.11g of copper contains
• $= 3.11 \times 9.4 \times {10}^{21}$
• = 29.234 × 10²¹ atoms

Hope you could get an idea from here.

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