Question

What is the mass of 1.2 x 1023 atoms of arsenic?

Answer 1

14.93 g

Step-by-step explanation:

First we convert 1.2 x 10²³ atoms of arsenic (As) into moles, using Avogadro's number:

• 1.2 x 10²³ atoms ÷ 6.023x10²³ atoms/mol = 0.199 mol As

Then we can calculate the mass of 0.199 moles of arsenic, using its molar mass:

• 0.199 mol * 74.92 g/mol = 14.93 g

Thus, 1.2x10²³ atoms of arsenic weigh 14.93 grams.