When $\mathop a\limits^x U$ is converted into $\mathop b\limits^y P$,which of the following represents the correct decrease in the number of neutrons?

When a sulphur atom becomes a sulphide ion,

Identify the isoelectronic pair from the following.

State whether the following statements are true or false:
$(i)$ Isobars have different atomic numbers.
$(ii)$ $_{14}^{30}\text{Si}$,$_{16}^{32}\text{S}$ are isotones.
$(iii)$ Niels Bohr was the first to suggest that the atom is spherical.
$(iv)$ Rutherford's model is accepted as the nuclear model of the atom.

Which property is different for neutral atoms of the two isotopes of the same element?

An atom which has lost one electron would be