An element ‘X’ has mass number = 27. If the number of electrons is given as 13, the number of neutrons will be _____.
14
Mass number = No. of protons + No. of neutrons
Since an atom is neutral, no. of protons = no. of electrons, which is necessary for charge balance.
Given, the number of electrons = 13. Therefore, the number of protons is 13.
So, number of neutrons will be 27 – 13 = 14