Precipitation reactions occur (1 Point) when group 1 cations are mixed with group 17 anions. when insoluble reactants are mixed. when ionic compounds react to form non-ionic products. predominantly with halide salts. when soluble ionic reactants combine to form insoluble products.

when soluble ionic reactants combine to form insoluble products.

Explanation:

Precipitation reactions are those reactions in which two soluble substances which are ionic in nature combine together forming insoluble salt. This insoluble salts is called precipitate and the reaction is called precipitation reaction. Precipitate is solid substance which is deposited at the bottom of the solution as insoluble material. This precipitate mostly formed in double replacement reaction.

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.

a saline water is fed to a reverse osmosis unit at flow rate o rotameter connected to reject (retentate) line reads 8 installed in reject and permeate line reads 15.2 milli siemens/cm and 300 micro siemens/com respectively.