TO CALIBERATE THE PH METER AND MEASURE PH OF THE GIVEN SOLUTION.

APPARATUS REQUIRED

•  Beaker

• Measuring cylinder 

• PH meter 

• Glass electrode

• Tissue paper 

CHEMICAL REQUIRED

• CH3COOH Solution (Weak Acid)

• NAOH Solution (Strong Base)

• Buffer solution of PH4 and 7.

THEORY

A PH meter is an electronic instrument used for measuring pH (acidity of alkalinity) of liquid (through speacial probes are. Sometimes used to measure pH of Semi-solid substance. A typical PH meter consists of special measuring probes (a glass electrode, and reference electroly connected are immersed into Sain they aid as battery. The gloss electrodes developes an electric potential that is directly related to H+ion, activity in solution and voltmeters mo sure potential different betn glass and reference electrodes Buffer soth is a solution which resist change in pH value on adding small Lamount of arid of base.

PROCEDURE:

• Connected electrode to pH meter and prepared pH 7.0 and pH 4.0 buffer solution.

• washed electrode with deionized water and dried it with tissue papers very gently

• Dipped the electrode in pH 7.0 buffer solution for 60 sec. by selecting pM mod and adjusted pH Using CAL control •Removed electrode from pl7.0. washed and dried as per instructions given earlier, Then similarly calibreted using 4.0 buffer solution 

•  Finally, we standarize the pH meter and then we dipped electrode in given Solution NAOH Solution (Strong base) and CH3COOH Solution (weak acid) And their pH reading were noted and compared with their respective pH value.

OBSERVATION

Observed pH value Of NaOH(strong base): 12.5pH
Observed pH value Of CH3COOH (weak acid):3.04pH
Real value of NAOH : 13 pH
Real value of CH3COOH : 2.873 pH

RESULT:

Thus, we measured the pH of given Solution 
which was found to be NaOH 12.5 and
CH3COOH 3.04

CONCLUSION

The pH meter can be calibrated and
the pH of given Solution can also be measured.