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An element forms a crystal with a face-centered cubic unit cell and an edge length of 200 pm. Calculate the density of the element if 200 g of it contains 24 × 10²³ atoms.

1. 24 × 10²³ g cm^−3
2. 41.6 g cm^−3
3. 2.46 g cm^−3
4. none of these

Correct answer: 41.6 g cm^−3

Solution

The density of the element is calculated using the formula ρ = (n × A) / (N_A × a³), where the given values result in a density of 41.6 g cm^−3, which is the correct answer.

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