The pH plays an important role in our daily life. Strength of acids and bases depends on the number of H+…
The pH plays an important role in our daily life. Strength of acids and bases depends on the number of H+ ions and OH– ions produced by these respectively. pH scale helps in predicting the strength of acids and bases by measuring hydrogen ion concentration in a solution.
Answer the following :
(a) What type of indicator is used to predict how strong an acid or base is ?
(b) Three solutions A, B and C showed pH as 3, 5 and 7. Which solution has the highest concentration of H+ ions ?
(c) What are strong acids and weak acids ?
Solution
(a) Universal indicator
(b) A/ (pH = 3)
(c)
• Strong acids give more H+ ions in water. / Strong acids pH 1-2
• Weak acids give less H+ ions in water. / Weak acids pH 6-7
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OR
(c) (i) When pH<5.6
(ii) Weak acid: acetic acid, formic acid ½+½