how many grams are in 0.02 moles of beryllium iodide
Beryllium iodide is BeI2. The molecular weight of BeI2 is 2(9.01) + 126.90 = 144.92g/mol. So, in 0.02 moles of BeI2, you have 0.02 * 144.92 = 2.9 grams (3 g if you want to stick to significant figures)