Question

Which of the following is paramagnetic Na2O Na2O2 KO2 K2O2

Answer 1

Answer:

KO2 is paramagnetic because of the existance of superoxides. There is no unpaired electrons either Na2+ or O2 2-. Hence it is diamagnetic.

KO2 is the right answer..

hopes it's helps you :)

Answer 2

Potassium superoxide $KO_2$ is paramagnetic.

Explanation:

The four substances given are

• $Na_2O$, where oxygen exists as an oxide$(O^{2-})$.

In oxide, there would be 10 electrons.

All electrons are paired, hence, it is diamagnetic.

• $Na_2O_2$, where oxygen exists as a peroxide$(O_2^{2-})$.

In peroxide, there would be 18 electrons.

The electronic configuration is $\sigma1s^2\sigma^*1s^2\sigma2s^2\sigma^*2s^2\sigma2p_z^2\pi2p_x^2\pi2p_y^2\pi^*2p_x^2\pi^*2p_y^2$.

All electrons are paired, hence, it is diamagnetic.

• $KO_2$, where oxygen exists as superoxide$(O_2^{-})$.

In superoxide, there would be 17 electrons.

The electronic configuration is $\sigma1s^2\sigma^*1s^2\sigma2s^2\sigma^*2s^2\sigma2p_z^2\pi2p_x^2\pi2p_y^2\pi^*2p_x^2\pi^*2p_y^1$ .

One electron is unpaired in the antibonding 2py orbital.

Hence, it is paramagnetic.

• $K_2O_2$, where oxygen exists as a peroxide$(O_2^{2-})$.

All electrons are paired, hence, it is also diamagnetic.