Answer:
D) 2.11 × 10^24
Step-by-step explanation:
Since we know from Avogadro's constant that 1 mole = 6.02 x 10^23 atoms, we can compare it to 3.50 moles. Let's call the unknown number of atoms x:
1 mole = 6.02 x 10^23 atoms
3.50 moles = x
Comparing the left side, how do we get from 1 mole to 3.50 moles? We multiply by 3.50, so do the same to the other side.
6.02 x 10^23 × 3.50 = 2.107 × 10^24, which is approximately 2.11 × 10^24 atoms to 2dp