Answer:
1.2×10²³ atoms.
Explanation:
In the problem, we see the data:
Mole of propanone = 0.20 mole
Calculating the number of atoms in propanone =?
According to Avogadro's principle, one mole of a substance contains 6.022×10²³ atoms.
This means that one mole of propanone also holds 6.022×10²³ atoms.
Thus, we can determine the atom count in 0.20 mole of propanone as:
1 mole of propanone contains 6.022×10²³ atoms.
Accordingly, 0.20 mole of propanone will have = 0.2 × 6.022×10²³ = 1.2×10²³ atoms.
Therefore, 0.20 mole of propanone contains
1.2×10²³ atoms.
Option d is the correct choice, as both belong to the alkali metals category (group one).