Question

Find the mass of 2.82x10 22 particles of CaF2​

Answer 1

I am using EE representing * 10 ^. There should be that button at your scientific calculator.

1 mol = 6.02EE23 [means 6.02 * 10^23)

Ca = 40.078 grams

F = 18.998 grams

CaF2 = 78.074 grams

2.82EE22 CaF2 particles * (1 mol CaF2 / 6.02EE23 CaF2 particles) * ( 78.074g CaF2 / 1 mol CaF2)

= (2.82EE22 CaF2 particles * 1 mol CaF2 * 78.074g CaF2) / (6.02EE23 CaF2 particles * 1 mol CaF2)

= (2.82EE22 * 78.074g CaF2) / (6.02EE23)

= approx 3.66g CaF2 (Sig figs! I hate them!)