Answer:
2.078x10^24
Step-by-step explanation:
No. of atoms of chlorine = 3.45 x 6.022x 10 ^23 x 1
= 2.078x10^24
( to find no. of atoms of, heres the formula i was taught No. of atoms = no. of moles x Avogadros constant x no. of atoms in the formula of compound)