Question

In the future you synthesize a new element. A neutral atom of the element, say 'X', has 4 electrons and 2 neutrons. How will you represent the nucleus of the element in your award winning paper?

• A. ${}_4^{2}X$
• B. ${}_4^{6}X$
• C. ${}_4^{4}X$
• D. ${}_2^{4}X$

Answer 1

The correct option is B ${}_4^{6}X$

The atomic number, Z, is equal to number of protons, which is equal to number of electrons, as the atom is neutral. So, Z= 4.
Also, the mass number, A, is given as N+Z, where N is the number of neutrons. So, A=N+Z=2+4=6. And, nucleus is represented as ${}_Z^{A}X$ so, this nucleus is represented as ${}_4^{6}X$