Bleaching Powder

Q.

Name three compounds of calcium which are used in day-to-day life and write one important use of each of them. [3 MARKS]

Q. Amit burns a magnesium ribbon in air and obtains compound “C₁”. Prakriti takes a small amount of powdered sulphur in a deflagrating spoon and heats it until it starts burning to obtain “C₂”. Abhinav drops a piece of aluminium foil into a freshly prepared solution of sodium hydroxide to obtain a gas “C₃”.

Now, choose the correct option.

अमित वायु में मैग्नीशियम रिबन जलाता है तथा यौगिक “C₁” प्राप्त करता है। प्रकृति उद्दहन चम्मच में चूर्णित सल्फर की अल्प मात्रा लेती है तथा इसे तब तक गर्म करती है जब तक यह जलना प्रारम्भ करके “C₂” नहीं दे देता। अभिनव सोडियम हाइड्रॉक्साइड के ताजे बने विलयन में ऐलुमिनियम पन्नी के एक टुकड़े को डालकर गैस “C₃” प्राप्त करता है।

अब सही विकल्प का चयन कीजिए।

1. C₃ burns with a pop sound when a burning match stick is brought near it and it is also released when powdered sulphur is dropped into a solution of freshly prepared solution of sodium hydroxide
   
   C₃ के समीप जलती हुई माचिस की तीली ले जाने पर यह पॉप ध्वनि के साथ जलती है तथा यह उस समय भी मुक्त होती है जब चूर्णित सल्फर को सोडियम हाइड्रॉक्साइड के ताजे बने विलयन में डाला जाता है
   
2. Aqueous solution of C₂ turns red litmus blue as it is basic in nature
   
   C₂ का जलीय विलयन लाल लिटमस को नीला कर देता है क्याेंकि यह क्षारीय प्रकृति का होता है
   
3. C₁ is a gas and its aqueous solution turns red litmus blue
   
   C₁ एक गैस है तथा इसका जलीय विलयन लाल लिटमस को नीला कर देता है
   
4. C₂ is a gas and its aqueous solution is acidic in nature and C₃ is also released when Zn reacts with sodium hydroxide solution
   
   C₂ एक गैस है तथा इसका जलीय विलयन अम्लीय प्रकृति का होता है तथा C₃ तब भी मुक्त होती है जब Zn की सोडियम हाइड्रॉक्साइड विलयन के साथ अभिक्रिया होती है
   

Q. Assertion :Sodium carbonate decompose on heating at a high temperature. Reason: Sodium bicarbonate on heating gives sodium carbonate along with carbon dioxide.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is incorrect but Reason is correct
4. Both Assertion and Reason are incorrect

Q. Chemical $A$ is used for water softening to remove temporary hardness. $A$ reacts with sodium carbonate to generate caustic soda. When $C{O}_2$ is bubbled through a solution of $A$, it turns cloudy. What is the chemical formula of $A$?

1. $CaC{O}_3$
2. $Ca(OH{)}_2$
3. $Ca(HC{O}_3{)}_2$
4. $CaO$

Q.

$CaOC{l}_2$ is the product of reaction between calcium hydroxide and ___ and is commonly called as ___.

1. Chlorine and bleaching powder.

2. Fluorine and talcum powder

3. Hydrogen and Gunpowder

4. Nitrogen and lime powder

Q. Potash alum contains ___________ number of water molecules.

1. 22
2. 24
3. 20
4. 25

Q. $0.5g$ of an oxalate was dissolved in water and the solution made to $100mL$. On titration $10mL$ of this solution required $15mL$ of $\frac{N}{20}KMn{O}_4$. Calculate the percentage of oxalate in the sample.

Q. Bleaching powder gives smell of chlorine because it:

1. is unstable
2. gives chlorine on exposure to atmosphere
3. is a mixture of chlorine and slaked lime
4. contains excess of chlorine

Q. Bleaching powder slowly decomposes to form:

1. $CaC{l}_2+Ca(Cl{O}_3{)}_2$
2. $CaO+C{l}_2$
3. $CaC{l}_2+Ca(OCl{)}_2$
4. $CaC{O}_3+C{l}_2$