Lakhmir Singh and Manjit Kaur Solutions for Chapter: Physical and Chemical Changes, Exercise 5: Questions Based on High Order Thinking Skills (HOTS)

When an ant stings a person, the solution of substance $\mathrm{A}$ is rubbed on the stung area of the skin to get relief from pain. The substance $\mathrm{A}$ is also used in kitchen for cooking purposes. Another substance $\mathrm{B}$ is sour in taste and contains an organic acid $\mathrm{C}$. It is used in making pickles. When a solution of $\mathrm{A}$ is mixed with $\mathrm{B}$, then a change $\mathrm{D}$ takes place to produce bubbles of gas $\mathrm{E}$. 

What are substances (i) $\mathrm{A}$, and (ii) $\mathrm{B}$?

When an ant stings a person, the solution of substance $\mathrm{A}$ is rubbed on the stung area of the skin to get relief from pain. The substance $\mathrm{A}$ is also used in kitchen for cooking purposes. Another substance $\mathrm{B}$ is sour in taste and contains an organic acid $\mathrm{C}$. It is used in making pickles. When a solution of $\mathrm{A}$ is mixed with $\mathrm{B}$, then a change $\mathrm{D}$ takes place to produce bubbles of gas $\mathrm{E}$. 

Name the acid $\mathrm{C}$.

When an ant stings a person, the solution of substance $\mathrm{A}$ is rubbed on the stung area of the skin to get relief from pain. The substance $\mathrm{A}$ is also used in kitchen for cooking purposes. Another substance $\mathrm{B}$ is sour in taste and contains an organic acid $\mathrm{C}$. It is used in making pickles. When a solution of $\mathrm{A}$ is mixed with $\mathrm{B}$, then a change $\mathrm{D}$ takes place to produce bubbles of gas $\mathrm{E}$. 

What type of change is $\mathrm{D}$?

When an ant stings a person, the solution of substance $\mathrm{A}$ is rubbed on the stung area of the skin to get relief from pain. The substance $\mathrm{A}$ is also used in kitchen for cooking purposes. Another substance $\mathrm{B}$ is sour in taste and contains an organic acid $\mathrm{C}$. It is used in making pickles. When a solution of $\mathrm{A}$ is mixed with $\mathrm{B}$, then a change $\mathrm{D}$ takes place to produce bubbles of gas $\mathrm{E}$.
Write the name of the gas $\mathrm{E}$. (Oxygen/Carbon dioxide)

When an object made of material $\mathrm{P}$ is kept immersed in the blue coloured solution $\mathrm{Q}$, then a chemical change takes place to form a green coloured solution $\mathrm{R}$ and a brown layer of substance $\mathrm{S}$ is deposited on the object. $\mathrm{P}$ is used for making nails and $\mathrm{S}$ is used for making electric wires.
What could the name of material $\mathrm{P}$ be? (Copper/Iron)

When an object made of material $\mathrm{P}$ is kept immersed in the blue coloured solution $\mathrm{Q}$, then a chemical change takes place to form a green coloured solution $\mathrm{R}$ and a brown layer of substance $\mathrm{S}$ is deposited on the object. $\mathrm{P}$ is used for making nails and $\mathrm{S}$ is used for making electric wires. 

Name the blue coloured solution $\mathrm{Q}$. 

When an object made of material $\mathrm{P}$ is kept immersed in the blue coloured solution $\mathrm{Q}$, then a chemical change takes place to form a green coloured solution $\mathrm{R}$ and a brown layer of substance $\mathrm{S}$ is deposited on the object. $\mathrm{P}$ is used for making nails and $\mathrm{S}$ is used for making electric wires.
Name the green coloured solution $\mathrm{R}$. (Copper sulphate/Iron sulphate)

When an object made of material $\mathrm{P}$ is kept immersed in the blue coloured solution $\mathrm{Q}$, then a chemical change takes place to form a green coloured solution $\mathrm{R}$ and a brown layer of substance $\mathrm{S}$ is deposited on the object. $\mathrm{P}$ is used for making nails and $\mathrm{S}$ is used for making electric wires. 

What could the substance $\mathrm{S}$ be?