Which one of these salts will form a basic solution on dissolving in water?

A. NaCl

B. KCN

C. NaNO3

D. NH4NO3

E. FeCl3

KCN forms a basic solution (option B)

Explanation:

Step 1: Data given

Acids have form AH, with conjugate base A-.

Bases have the form BOH, with conjugate acid B+.

Strong acids have weak conjugate bases

Strong bases have weak conjugate acids

Weak acids have strong conjugate bases

Weak base have strong conjugate acids

a) NaCl.

Na + is a conjugate acid of NaOH, what is a strong base.

Cl - is the conjugate base of HCl, what is a strong acid.

They form a neutral solution

b) KCN.

K + is a conjugate acid of KOH, what is a strong base.

CN - is the conjugate base of HCN, what is a weak acid.

K + is a weak conjugate acid, CN - is a stronger conjugate base

They form a basic solution

c) NaNO3.

Na + is a conjugate acid of NaOH, what is a strong base.

NO3 - is the conjugate base of HNO3, what is a strong acid.

They will form a neutral solution

d) NH4NO3.

NH4 + (ammonium) is the conjugate acid of NH3, what is a moderately strong base.

NO3 - is the conjugate base of HNO3, what is a strong acid.

Ammonium is a stronger conjugate acid, nitrate is a weak conjugate base.

The solution is acid.

e) FeCl3 is an acid salt because Fe (OH) 3 is weak base and HCl is a strong acid. pH is less than 7.

Fe^3 + is the conjugate acid of Fe (OH) 3, what is weak base.

Cl - is the conjugate base of HCl, what is a strong acid.

Fe^3 + is a 'stronger' conjugate acid, Cl - is a weaker conjugate base.

They solution is acid