Answer:
0.67 g
Explanation:
We know that 1 mole of an element is 6.02 x 10^(23) atoms
Now, arsenic has 5.49 × 10²¹ atoms
Thus;
Number of moles of arsenic = 5.49 × 10²¹ × 1/6.02 x 10^(23) = 9 × 10^(-3) moles
We are told that;
one mole of arsenic = 74.92 g.
Thus, 9 × 10^(-3) moles = 9 × 10^(-3) × 74.92/1 = 0.67428 g ≈ 0.67 g
