Which of the following reactions leads to the production of bleaching powder?

Question

Examoogle · Accepted Answer

The correct answer is Option B: Ca(OH) 2 + Cl 2 → CaOCl 2 + H 2 O. Bleaching powder, chemically known as calcium oxychloride ($CaOCl_{2}$), is produced by the action of chlorine gas on dry slaked lime. It is a yellowish-white powder that serves as a powerful oxidizing and bleaching agent.

Step-by-Step Solution & Concepts:
Bleaching powder, chemically known as calcium oxychloride ($CaOCl_{2}$), is produced by the action of chlorine gas on dry slaked lime. It is a yellowish-white powder that serves as a powerful oxidizing and bleaching agent.

Working Principle: The production process is a dry chemical synthesis. Chlorine gas ($Cl_{2}$) is passed through dry calcium hydroxide ($Ca(OH)_{2}$), which is also known as slaked lime. The reaction forms calcium oxychloride ($CaOCl_{2}$) and releases water as a byproduct. The reaction is represented by: $$Ca(OH)_{2} + Cl_{2} \rightarrow CaOCl_{2} + H_{2}O$$

Key Formulas: $Ca(OH)_{2} + Cl_{2} \rightarrow CaOCl_{2} + H_{2}O$ — Chemical reaction for the production of bleaching powder

Key Points: The chemical name of bleaching powder is Calcium Oxychloride.; Dry slaked lime must be used to ensure the efficiency of the reaction.; Bleaching powder is unstable and loses chlorine upon exposure to atmospheric $CO_{2}$.

Advantages: Excellent disinfectant for water purification.; Effective bleaching agent in textile and paper industries.

Disadvantages: Releases chlorine gas if it reacts with dilute acids.; Sensitive to moisture and carbon dioxide, which reduces its effectiveness over time.

Applications: Used for disinfecting drinking water to make it germ-free.; Used in the textile industry for bleaching cotton and linen.

Additional Info: Option A ($CaCO_{3} + 2HCl \rightarrow CaCl_{2} + CO_{2} + H_{2}O$) represents the reaction of calcium carbonate with hydrochloric acid.. Option C ($Ca(OH)_{2} + CO_{2} \rightarrow CaCO_{3} + H_{2}O$) is the chemical test for carbon dioxide (turning lime water milky).. Option D ($CaO + H_{2}O \rightarrow Ca(OH)_{2}$) is the slaking of lime (exothermic reaction).

Answer: B is correct — Bleaching powder is produced by passing chlorine gas over dry slaked lime.

Exam Tip: Remember that bleaching powder undergoes decomposition with atmospheric carbon dioxide, known as 'carbonation', which is why it is often stored in airtight containers.

Examoogle · Answer

Option A: CaCO 3 + HCl → CaCl 2 + CO 2 + H 2 O

Examoogle · Answer

Option C: Ca(OH) 2 + CO 2 → CaCO 3 + H 2 O

Examoogle · Answer

Option D: CaO + H 2 O → Ca(OH) 2

Correct Answer

Solve 10,000+ More Questions with AI Tutor

Discussion (0)

Correct Answer

Solve 10,000+ More Questions with AI Tutor

Related Questions

Discussion (0)