Which statement explains why a c–o bond is
more polar than a f–o bond?
(1) at stp, carbon has a greater density than
fluorine.
(2) a carbon atom has more valence electrons
than a fluorine atom.
(3) the difference in electronegativity between
carbon and oxygen is greater than that
between fluorine and oxygen.
(4) the difference in first ionization energy
between carbon and oxygen is greater than
that between fluorine and oxygen.

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.