Request a call back

Join NOW to get access to exclusive study material for best results

CBSE Class 10 Answered

1.A farmer has grown the petunia flowers on his field. He observed that the colour of the flowers started changing from blue to reddish purple.

• What could be the possible reason for the change in colour?

⚫ What role is played by petunia flowers?

• Suggest any two substances playing the same role in the field of agriculture. • What should be added by the farmer to treat the soil?

What type of reaction will take place during treatment of soil?

2. A metal X reacts with HCI to liberate gas A but its compound Y releases gas B with HCI along with the salt CaCl,.

Name the metal X.

• Identify gas A and how will you test for it?

⚫ Name the salt Y and give its molecular formula.

• Identify gas B and how will you test for it? What type of reaction takes place when X reacts with HCI?

3. A sodium salt 'A' is used while baking a cake. It makes the cake fluffy and

spongy due to the release of gas 'B'.

Identify salt 'A'.

⚫ What is the common name of this salt?

⚫ Which gas is released during the process?

• How will you test for gas 'B'?

4. Anita's mother asked her to store the pickle in some bowl. She kept the pickle

in a brass bowl.

Was she right in doing that? Why or why not?

Asked by 9414612ji | 19 Aug, 2022, 08:25: AM
Expert Answer
Dear Student,
Kindly ask one query at a time.
 
Answer for first chemistry question, 

Qus: A metal X reacts with HCI to liberate gas A but its compound Y releases gas B with HCI along with the salt CaCl,.

Name the metal X.

• Identify gas A and how will you test for it?

Name the salt Y and give its molecular formula.

• Identify gas B and how will you test for it? What type of reaction takes place when X reacts with HCI?

The answer is given below,
 

Salt of X Metal i.e Y reacts with HCl to produce salt CaCl2 and gas B.

(i)As the product CaCl2 is a calcium salt, we can conclude that the reactant Y salt is a Calcium metal salt.

(ii)Carbonates of metal on reacting with HCl produce Chlorides of metal along with release CO2 gas.

From (i) and (ii), the salt must be CaCO3 and the reaction would be as below,

CaCO3 + HCl → CaCl2 + CO2

As Y is CaCO3, hence, X must be Calcium metal.

Metals on reaction with HCl produce corresponding chlorides and hydrogen gas. This is Displacement reaction wherein metal displaces hydroen from HCl to form metal chlorides.

Ca + HCl → CaCl2 + H2

Thus,

X = Ca

Y = CaCO3

A = H2 gas

The gas A is hydrogen gas which can be confirmed by holding burning candle in the released gas. Hydrogen gas burns with pop sound.

B = CO2 gas

The gas B is carbon dioxide which can be confirmed by lime water test. Carbon dioxide turns lime water milky.

 

 

Answered by | 19 Aug, 2022, 12:52: PM
CBSE 10 - Chemistry
Asked by manisha.5154 | 15 Jun, 2022, 02:52: PM
ANSWERED BY EXPERT
CBSE 10 - Chemistry
Asked by ranishoba947 | 10 May, 2022, 09:04: PM
ANSWERED BY EXPERT
CBSE 10 - Chemistry
Asked by Trisha Gupta | 23 Nov, 2021, 12:29: AM
ANSWERED BY EXPERT
CBSE 10 - Chemistry
Asked by anshika.dubey9809 | 11 Nov, 2021, 07:42: PM
ANSWERED BY EXPERT
CBSE 10 - Chemistry
Asked by bhavikabhatia1125 | 10 Jul, 2021, 10:27: PM
ANSWERED BY EXPERT
CBSE 10 - Chemistry
Asked by nitikakaliramana466 | 14 May, 2021, 09:37: AM
ANSWERED BY EXPERT
CBSE 10 - Chemistry
Asked by ayan1.chatterjee | 07 May, 2021, 08:05: PM
ANSWERED BY EXPERT
×