You see a structural formula and which the symbols for elements are connected by a long dash you can assume that the chemical bonds in the compound are

When you see a long dash joining two elements in the structural formula of a chemical molecule you can assume that the chemical bonds in the compound are simple bonds.

In the representation of chemical molecules long dashes are used to represent simple bonds since these bonds are longer than double and triple bonds, which are represented by = and ≡ respectively.

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.

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