Answer:
Since in a chloride ion, we have an additional electron
you might think that it will affect the mass but the mass of an electron is almost negligible so we will ignore that
Amount of ions in 1 mol = 6.022 * 10^23
Amount of ions in 0.486 moles = 0.486 * (6.022*10^23)
Amunt of ions in 0.486 moles = 2.9 * 10^23 ions
Hence, option 1 is correct
