The total number of electrons in a nitrogen atom is 7. Find the number of valence electrons in it.

An atom of an element X may be written as .

(a) What does the figure 9 indicate?

(b) What does the figure 4 indicate?

(c) What is the number of protons in atom X?

(d) What is the number of neutrons in atom X?

(e) What is the number of electrons in atom X?

(f) How many electrons are there in the outermost shell of an atom of element X?

(g) Write the symbol of ion formed by an element Z is 2, 8, 8.

The electronic configuration of an element Z is 2, 8, 8.

(a) What is the atomic number of the element?

(b) State whether element Z is a metal or a non-metal.

(c) What type of ion (if any) will be formed by an atom of element Z? Why?

(d) What is special about the outermost electron shell or the atom of this element?

(e) Give the name and symbol of element Z.

(f) Name the group of elements to which Z belongs.

What is the general name of the elements having 8 electrons in the valence shell of their atoms?

Which noble gas has less than 8 electrons in the valence shell of its atom? What is this number?