An elements has electronic configuration $2,8,18,1$. If its atomic weight is $63$, then how many neutrons will be present in its nucleus?

Q. An atom has the electronic configuration of $1s^2,2s^2,2p^6,3s^{2}3p^{6}3d^{10},4s^{2}4p^2$. Its atomic weight is $80$. Its atomic number and the number of neutrons in its nucleus shall be:-

Q. The mass number of an element is 41 and it has 21 neutrons in its nucleus. The electronic configuration of the element is:

Q.

An atom has 26 electrons and its atomic weight is 56. The number of neutrons in the nucleus of the atom will be

Q. What do you understand by the term "electronic configuration" of an element? Write down the electronic configuration of oxygen (At. No. = 8).
An element has an atomic number 12. How many electrons will be present in the K, L and M energy shells of its atom?

Q. An atom of an element contains $13$ electrons. Its nucleus has $14$ neutrons. Find out its atomic number and approximate atomic mass. An isotope has atomic mass $2$ units higher. What will be the number of protons, neutrons and electrons in the isotope?