Question

Assertion: Calcium oxide is a base but not an alkali.
           Reason: Calcium oxide is insoluble in water.
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.               ·
(b) If both Assertion and Reason are true but Reason is not the correct -explanation of Assertion.
(c) If Assertion is true but Reason is false.
(d) If Reason is true but Assertion is false.
(e). If both Assertion and Reason are false.
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Answer 1

Answer:

A is the right option because alkali means which is soluble in water and if it does not then it is not an alkali

Answer 2

(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion is the correct option

Explanation:

• Calcium oxide $(cao)$, sometimes known as quicklime or burnt lime, is a chemical substance that is frequently utilised. At room temperature, it is a white, caustic, alkaline, crystalline solid. It is a commodity chemical, as is a chemical derivative (calcium hydroxide, of which quicklime is the basic anhydride).
• In mortar and plaster, quicklime or $cao$ is utilised as hydrated or "slaked lime" $Ca(OH)2$ (mineral "portlandite"). Lime is also employed in glass manufacture, and its ability to react with silicates is used to eliminate impurities like "slag" in modern metal production industries (steel in particular).

Calcium oxide is a base but not an alkali:

• Calcium oxide is not an alkali, but it is a base. Calcium oxide is insoluble in water for this reason. Assertion: Litmus paper does not change colour when it comes into contact with distilled water. The purpose of Litmus Paper is to determine whether or not a solution is acidic or basic.