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प्रश्न
What is the difference between an alkali and a base?
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उत्तर
| Alkali | Base | |
| 1. | An alkali is a basic hydroxide that, when dissolved in water, produces hydroxyl (OH−) ions, the only negatively charged ions. | A base is a chemical compound that, when reacting with a hydronium ion or H+ ions furnished by an acid, forms salt and water only. |
| 2. | All alkalis are water soluble. | Bases may or may not be water soluble. |
| 3. | All alkalis are bases | All bases are not alkalis. |
| 4. | Examples are NaOH, KOH, Ca(OH)2. | Examples are CuO, Mg(OH)2. |
संबंधित प्रश्न
Give one example in the following case:
An oxide which is a base.
Salts are neutral.
All bases are alkalis.
Match the important chemicals given in Column (A) with the chemical formulae given in Column (B)
| Column (A) | Column (B) |
| (a) Plaster of Paris | Ca(OH)2 |
| (b) Gypsum | CaSO4. 1/2 H2O |
| (c) Bleaching Powder | CaSO4.2H7O |
| (d) Slaked Lime | CaOCl2 |
Boojho, Paheli and their friend Golu were provided with a test tube each containing China rose solution which was pink in colour. Boojho added two drops of solution ‘A’ in his test tube and got dark pink colour. Paheli added 2 drops of solution ‘B’ to her test tube and got green colour. Golu added 2 drops of solution ‘C’ but could not get any change in colour. Suggest the possible cause for the variation in their results.
Match the following:
| 1. | Sulphuric acid | a. | Weak base |
| 2. | Sodium hydroxide | b. | Strong acid |
| 3. | Acetic acid | c. | Strong base |
| 4. | Ammonium hydroxide | d. | Weak acid |
Which of the following solutions do not conduct electricity?
______ alkali has a relatively high percentage of alkali in its aqueous solution.
One of the events that does not occur during photosynthesis is ______.
A small amount of copper oxide was taken in a beaker and dilute hydrochloric acid was added with continuous stirring of the solution. Name the compound formed and state the colour of its solution. Write the balanced chemical equation for the reaction that occurs. Based on the reaction, state the nature (acidic/basic) of copper oxide.
