Question

Strikethrough the odd one out. Give reasons for your choice.

Potassium, sodium, calcium, magnesium, silicon

Answer 1

• Potassium$\left(\mathrm{K}\right)$ is a silvery-white colored metal.
• Sodium$\left(\mathrm{Na}\right)$ is also a silvery-white colored highly reactive metal.
• Calcium$\left(\mathrm{Ca}\right)$ is a white-colored metal.
• Magnesium$\left(\mathrm{Mg}\right)$ is a silvery-white metal that burns with a dazzling light.
• Silicon$\left(\mathrm{Si}\right)$ is a metalloid with a bluish-grey metallic luster.

Hence, the odd one out is Silicon, Which is a metalloid

Potassium, sodium, calcium, magnesium, silicon

Metals - Elements that have an excess of electrons and a tendency to donate them are generally considered metals. For example - Sodium$\left(\mathrm{Na}\right)$, Silver$\left(\mathrm{Ag}\right)$, etc.

Metalloids - Metalloids can be defined as chemical elements whose physical and chemical properties fall in between the metal and non-metal categories. For example - Silicon$\left(\mathrm{Si}\right)$, Germanium$\left(\mathrm{Ge}\right)$, etc.