The acid-base titration involves a neutralisation reaction. Here an acid or base of known concentration is used to determine the concentration of a given base or acid by neutralisation. In this type of titration, a drop of an indicator is used at the start, which changes its colour to indicate the endpoint. The indicator changes the colour with the change in the pH of the solution. A suitable indicator should be used to determine the equivalence point and reduce indicator error.
1. What is the molarity of the solution of barium hydroxide, if 35 ml of 0.1 M HCl is used in the titration of 25 ml of the barium hydroxide solution?
2. Which of the following titrations will have the equivalence point at a pH more than 8?
(a) HCl and NH3
(b) CH3COOH and NH3
(c) HCl and NaOH
(d) CH3COOH and NaOH
3. Which of the following is used as an indicator in the titration of a strong acid and a weak base?
(b) Thymol blue
(d) Methyl orange
4. Which of the following is used as an indicator in the titration of a weak acid and a strong base?
(a) Bromothymol blue (6 to 7.5)
(b) Methyl orange (3 to 4)
(c) Methyl red (5 to 6)
(d) Phenolphthalein (8 to 9.6)
5. The ideal indicator for the titration of strong acid and weak base should have pH range between
6. A difference between strong and weak acid is
(a) presence and absence of halogen ions
(b) negative and positive pH
(c) complete and partial ionisation
(d) proton donation and electron acceptance
7. Find the concentration of HCl, if 10 ml of 0.5 M Ca(OH)2 is required to titrate 50 ml of HCl.
(a) 5 M
(b) 1/10 M
(c) 10 M
(d) 1/5 M
8. Which of the following is a buffer solution?
(a) H2SO4 + CuSO4
(b) CH3COOH + CH3COONH4
(c) NaCl + NaOH
(d) CH3COONa + CH3COOH
9. If 30 ml of acid is neutralised by 15 ml of 0.2 N alkali, then the concentration of acid is
(a) 0.4 N
(b) 0.1 N
(c) 0.3 N
(d) 0.15 N
10. What is the concentration of the sulphuric acid solution, if 100 ml of the solution is neutralised by 50 ml of 0.5 M Ba(OH)2 solution?
(a) 0.25 M
(b) 50 M
(c) 0.5 M
(d) 100 M