An unknown solution has a ph of 6.8. which of these chemicals is likely to increase the ph the most when added to the solution? a. naoh b. hcl c. nh3 d. hno3

A. NaOH.

Explanation:

The pH  of the solution = 6.8.

So, NaOH and NH₃ "bases" will increase the pH of the solution.

while, HCl and HNO₃ "acids" will increase the acidity of the solution, thus pH will decrease.

But, NaOH will increase the pH of the solution the most because it is dissociates completely to OH⁻ , while NH₃ is weakly ionized "does not dissociate completely".

So, NaOH will increase the pH the most when added to the solution.

NaOH

Explanation:

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.