The sodium nucleus ${}_{11}^{23}$ Na contains

Q. The only, most stable nucleus formed by bombarding either ${}_{13}^{27}Al$ by neutrons or ${}_{11}^{23}Na$ by deutrons is:

Q. How many atoms are contained in $23g$ of sodium? ($Na=23u$)

Q. A solution of sodium sulphate contains $92\text{g}$ of $N{a}^{+}$ ions per kilogram of water. The molality of $N{a}^{+}$ ions in that solution in ${\text{mol kg}}^{-1}$ is: