Determine whether each statement describes an electromagnetic wave, a mechanical wave, or both types of wave.

The question is incomplete, the complete question is;

Which statement describes a difference between electromagnetic and mechanical waves?

A. Mechanical waves cannot be longitudinal, but electromagnetic waves can.

B. Electromagnetic waves cannot move particles, but mechanical waves can.

C. Electromagnetic waves do not require a medium, but mechanical waves do.

D. Mechanical waves do not transfer energy, but electromagnetic waves do.

Electromagnetic waves do not require a medium, but mechanical waves do.

Explanation:

A wave is defined as a disturbance along a medium which transfers energy. Waves may be classified as mechanical waves or electromagnetic waves based on their medium of propagation.

A mechanical wave requires a material medium for propagation. An example of a mechanical wave is sound waves. Sound waves are propagated in air.

Electromagnetic waves do not require a material medium for propagation. They can travel through space. An example of electromagnetic waves is light waves.

alkaline metals are lithium, sodium, rubidium, potassium, cesium and francium.

alkali metals have electronegativity from 0.7 to 1, lowest in periodic table of elements, which means that alkali metals (i group in periodic table) has positive oxidation number in compounds.

electronegativity is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself.

alkaline metals (far left in main group) have lowest ionizations energy and easy remove valence electrons,

for example, potassium is the alkali metal and has a single valence electron in the outer electron shell.

electron configuration of potassium is: ₁₉k 1s²2s²2p⁶3s²3p⁶4s¹.

they can not exist alone in nature, because they are very reactive.