Salt is dissolved in a flask of tap water. distilling the mixture causes the salt to separate from the water. which type of energy is required to begin the distilling process?
a)chemical energy
d).electrical energy
c).mechanical energy (motion)
d).thermal energy

The correct option is D.

Thermal energy is the energy derived from heat. To separate the mixture of salt and water, heat has to be applied to the mixture. The energy from the heat will make the molecules of the water to gain kinetic energy and to move around the container more rapidly until the inter molecular forces between the molecules are broken and they escape as steam into the atmosphere. It is only the salt particles that will be left behind after all the water has evaporated.

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.