Question

how many of the following elements have 2 unpaired electrons in the ground state? C, O, Ti, Si a) 1 b) 3 c) 4 d) 2

Answer 1

Answer;

c) 4

Explanation;

• An unpaired electron is an electron that occupies an orbital of an atom singly, rather than as part of an electron pair.
• To find out if the electrons inside an orbital are paired or not you need to find out the maximum electrons the subshell can hold. If the electrons in the subshell are less than the maximum electrons it can hold the electron in any of the orbital can be unpaired.

• Oxygen, O, has two unpaired electrons.
• Carbon, C, has two unpaired electrons
• Ti and Si have two unpaired electrons

Answer 2

Answer: Option (c) is the correct answer.

Explanation:

Atomic number of carbon is 6 and its electronic configuration is $1s^{2}2s^{2}2p^{2}$.

Atomic number of oxygen is 8 and its electronic configuration is $1s^{2}2s^{2}2p^{4}$.

Atomic number of titanium is 2 and its electronic configuration is $[Ar]4s^{2}3d^{2}$.

Atomic number of silicon is 14 and its electronic configuration is $[Ne]3s^{2}3p^{2}$.

Therefore, we can conclude that out of the given options all the 4 elements have 2 unpaired electrons in the ground state.