The atomic number of sodium is 11 and its mass number is 23. It has
(a) 11 neutrons and 12 protons
(b) 12 protons and 11 electrons
(c) 11 electrons and 12 neutrons
(d) 12 electrons and 11 neutrons.

Correct: (c) 11 electrons and 12 neutrons

Explanation: The atomic number and mass number of sodium are 11 and 23 respectively.

Hence, the number of protons in sodium =11 and number of nucleons i.e. proton and neutrons in sodium =23.   

Thus, number of neutrons is 23-11 = 12 

Since no. of protons = no. of electrons =11.


Simply Easy Learning

Updated on: 14-Mar-2023


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