Question

Use the following table to answer the question. Strong acids Weak acids Weak bases Strong bases HBr CH3COOH NH3 NaOH HCl HF NH4OH KOH H2SO4 HCN Cu(OH)2 Ca(OH)2 Which of these salts has the highest pH? K2SO4 Cu2SO4 NH4Cl NaCH3COO

Answer 1

Answer: The salt which has the highest pH is $CH_3COONa$

Explanation: Salts are formed by the reaction of acid and base. General equation for the generation of salt is given by:

$HX+BOH\rightarrow BX+H_2O$

The given salts are formed from the reaction of acids and bases.

1) $K_2SO_4$

This is a salt formed by the reaction of strong base (KOH) and strong acid $(H_2SO_4)$ . So, this salt is a neutral salt.

$H_2SO_4+2KOH\rightarrow K_2SO_4+2H_2O$

2) $CuSO_4$

This is a salt which is formed by the reaction of weak base $(Cu(OH)_2)$ and strong acid $(H_2SO_4)$. So, this salt is an acidic salt.

$H_2SO_4+Cu(OH)_2\rightarrow CuSO_4+2H_2O$

3) $NH_4Cl$

This is a salt which is formed by the reaction of weak base $(NH_3)$ and strong acid (HCl). So, this salt is an acidic salt.

$HCl+NH_3\rightarrow NH_4Cl$

4) $CH_3COONa$

This is a salt which is formed by the reaction of  strong base (NaOH) and weak acid $(CH_3COOH)$. So, this salt is a basic salt.

$CH_3COOH+NaOH\rightarrow CH_3COONa+H_2O$

Now, we have to find the salt which has the highest pH value.

Highest pH value means that the salt must be basic in nature and from the given salts, only $CH_3COONa$ is basic salt. Hence, this salt has the highest pH value.

Answer 2

Answer:

D

Explanation: