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प्रश्न
What is meant by strong bases and weak bases? Classify the following into strong bases and weak bases:
NH4OH, Ca(OH)2, NaOH, KOH, Mg(OH)2
उत्तर
Strong bases ionise completely in water, producing huge amounts of hydroxide ions (OH− ions). Generally, basic or alkali solutions of pH 8, 9 and 10 are considered weak bases or alkalis.
Weak bases ionise partially in water, producing less amounts of hydroxide ions (OH− ions).
Basic or alkali solutions of pH 11,12,13 and 14 are considered strong bases or alkalis.
Let us classify the given bases as strong or weak.
| Strong bases | Weak bases |
| Sodium hydroxide, NaOH Potassium hydroxide, KOH |
Ammonium hydroxide, NH4OH Calcium hydroxide, Ca(OH)2 Magnesium hydroxide, Mg(OH)2 |
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