As we learned, matter exists in different states--solid, liquid and gas. which one of these could be described as having low density and a volume that is not definite? a. liquidsb. gasesc. solidsd. both solids and liquidse. none of the above

Gas

Explanation:

The properties of the three states of matter are:

solid : fixed shape, fixed volume, high density as the intermolecular forces are strong and the particles cannot move here there. Only vibrations are possible.

Liquid: Fixed volume but shape depends upon the container, density lower than solid but higher than air.

Gas: Not fixed volume and not fixed shape also. The density is least among the three states of matter. There are leas strong force of interactions between molecules. the thermal energy is highest among the three states of matter.

Thus answer is gas.

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.