Question

Different nuclides of the same element have1) the same number of protons and the same number of neutrons.2) the same number of protons but different numbers of neutrons.3) the same number of neutrons but different numbers of protons.4) different numbers of protons and different numbers of neutrons.

Answer 1

If the nuclides belong to the same element, then, they have equal number of protons. However, they have different number of protons in order to be different nuclides.

Then, you can conlude:

2) the same number of protons but different numbers of neutrons.