A sample of 5.4 g of aluminium (M=27 g mol^-1) is a ccp crystal. Use N_A = 6.022x10^23 mol^-1. The number of tetrahedral voids in the sample is xx10^22. Find x (two decimals).

JEE Main levelNumerical answerDifficulty 2 of 3ss121

A sample of $5.4 g$ of aluminium ( $M = 27 g mo l^{- 1}$ ) is a ccp crystal. Use $N_{A} = 6.022 \times 1 0^{23} mo l^{- 1}$ . The number of tetrahedral voids in the sample is $x \times 1 0^{22}$ . Find $x$ (two decimals).

Numerical answer type, tolerance 0.03.

Moles of Al

= 5.4/27 = 0.200

; atoms

= 0.200 \times 6.022 \times 1 0^{23} = 1.2044 \times 1 0^{23}

. Tetrahedral voids

= 2 \times

atoms

= 2.4088 \times 1 0^{23} = 24.09 \times 1 0^{22}