Home > Community > Are solutions of the following salts acidic, basic, or neutra: lFeBr3, LiNo3, KNO2, and NaCN?
Upvote

13

Downvote
+ Inorganic chemistry
+ Acids
+ Chemistry
+ Organic chemistry
Posted by
Krishna

Are solutions of the following salts acidic, basic, or neutra: lFeBr3, LiNo3, KNO2, and NaCN?

Connor Smith  Follow

As FeBr3 is a salt of weak base Fe(OH)3 and strong acid, its aqueous solution will be acidic. Fe^3+ + 6H2O → Fe(OH)3 + 3 H3O+

LiNO3 is a salt of strong acid HNO3 and strong base. It doesn't hydrolyse, it dissociates into aquated ions only in water. So, its aqueous solution will be neutral.

KNO2 is a salt of strong base KOH and weak acid HNO2. So, its aqueous solution will be alkaline.

NO2^- + H2O → HNO2 + OH-

NaCN is a salt of strong base NaOH and weak acid HCN. Hence, its aqueous solution is also alkaline.

CN- + H2O → HCN + OH-

Hope this helps.

More

Upvote

VOTE

Downvote
Christopher Chun  Follow

FeBr3 → acidic

LiNO3 → neutral

KNO2 → basic

NaCN → basic

To answer to this question you have to compare the Ka and the Kb of acids and bases used to obtain the salts you are considering.

If the difference is less than 10^-1 or 10^+1(Ex. Ka/Kb → 10^-3/10^-4) you can consider the salt almost neutral.

If Ka – Kb is lower then 10^-1 (Ex. A/B → 10^–3/10^-5) the salt is acidic.

If Kb – Ka is lower then 10^-1 (Ex. A/B → 10^–5/10^-3) the salt is basic.

More

Upvote

VOTE

Downvote