Each of four groups of students determined and recorded the melting point of a solid compound. if the actual melting point is 113°c, which group had the best precision?

Group 4

Explanation:

Precision means the closeness of repeated measurement.

Accuracy means the closeness of measurement to its true value.

Measurement can be precise but not accurate.

Group 4 measurement has the lowest range which is 110 - 111, hence, they are the most precise in their measurement.

(See the attached image)

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.