Three nuclides are listed below.
X:A=37,Z=17Y:A=37,Z=18Z:A=35,Z=17
(i) Calculate the neutron number N for each of the nuclides X, Y and Z.
(ii) Identify every possible pair among X, Y and Z that are (a) isotopes, (b) isobars and (c) isotones. State the reason for each identification.