EXPERIMENT 6 - Write in LHS of the record
Conclusion
i) The pH of acid solution is less than 7
ii) The pH of an acid solution increases with decrease in concentration.
EXPT NO. 6 CONTENT BASED EXPERIMENT (Write in RHS OF THE RECORD) DATE :
To determine pH of HCl solution of various concentrations by using pH paper or universal indicator
Aim: To determine pH of HCl solution of various concentrations by using pH paper or universal indicator
Apparatus: Test tubes, test tube stand
Chemicals: 0.1 M, 0.01 M, 0.001M HCl solution, pH paper or universal indicator
Teory: pH = - log [H+]
for acidic solution, pH < 7, Basic solution pH > 7, and neutral solution pH = 7.
The value of pH changes with change in concentration of HCl
PROCEDURE
1. Using pH paper. Put 2-3 drops of the sample solutions on pH paper by means of a glass rod and observe the colour on the pH paper. Now compare the shade of colour formed with various colours given on the pH indicator chart. From this, note the approximate pH of the sample solution and record in the table.
2. USING UNIVERSAL INDICATOR SOLUTION :- Take five test tubes, clean and dry them. Take 5ml of each given solution in different test tubes with the help of measuring cylinder. Now put 2-3 drops of universal indicator in each test tube by means of a dropper. Note the colour of solution in each test tube and compare its colour with different colour shades as given in the pH indicator chart. After comparing the colour in each tube, note the pH of solution and record in the table.
RESULT
i) The pH of acid solution is less than 7
ii) The pH of an acid solution increases with decrease in concentration.
