1.

pH value of which one of the following is NOT equal to one ?

Answer»

`0.1" M HNO"_(3)`
`0.05" M "H_(2)SO_(4)`
`0.1" M "CH_(3)COOH`
`50" cm"^(3)` of 0.4 M HCl + 50 `"cm"^(3)` of `0.2" M NAOH"`

Solution :`pH=-log[H^(+)]`
(a) VALUE of `pH=0.1" M HNO"_(3)=-log[0.1]=1`
(b) Value of `pH=0.05H_(2)SO_(4)=-log[2xx0.05]=1`
(c) Value of `pH=0.1"M "CH_(3)COOH!=1` as it is a weak acid so, will not undergo complete ionization.
(d) Milli - equivalent of acid `=50xx0.4=20`
Milli-equivalent of base `=50xx0.2=10`
Remaining acid `=20-10=10` milli-eq.
`[H^(+)]=(10)/(50+50)=(10)/(100)=0.1`
`pH=-log[H^(+)]=1`.


Discussion

No Comment Found

Related InterviewSolutions