Give the number of electrons in the species 

Write the complete symbol for the atom with the given atomic number (Z) and atomic number (A).
(i) Z = 17,   A = 35 
(ii) Z = 92,  A = 233
(iii) Z = 4,   A = 9.

104. An ion with mass number 37 possesses one unit of negative charge. If the ion contains 11.1 % more neutrons than the electrons, find the symbol of the ion. 

What is the atomic number and mass number of A³⁺ ion with 21 electrons and 25 neutrons?

Define isotopes, isobars and isotones.

Name different isotopes of hydrogen. Give their atomic numbers and mass numbers.

Isotopes of an element have similar chemical properties and isobars have different chemical properties. Explain.