Question

9.A neutral atom of an element has 2 electrons in the first energy level, 8 in the second energy level and 8 in the third energy level. This information does not necessarily tell us:



a) the atomic number of the element.

b) the total number of electrons in s orbitals.

c) the total number of electrons in p orbitals.

d) the number of neutrons in the nucleus of an atom of the element.

Answer 1

Answer:

d) the number of neutrons in the nucleus of an atom of the element.

Answer 2

The correct option is d.

• A neutral atom of an element has 2 electrons in the first energy level, 8 in the second energy level and 8 in the third energy level. Hence its electronic configuration is given as follows-
• ${1s}^{2} {2s}^{2} {2p}^{6} {3s}^{2} {3p}^{6}$
• The total number of electrons in the "s" orbital is 2+2+2=6.
• The total number of electrons in the "p" orbital is 6+6=12.
• The atomic number of the element is 2+8+8=18.
• But we can not say the number of neutrons.