Embibe Experts Solutions for Chapter: Sorting Materials into Groups, Exercise 1: Exercise

Navika’s teacher asked all the students to bring lemon, sugar and water for Nimbu paani making activity in the class. Navika added sugar and salt to water and stirred it with a spoon. She saw that sugar and salt got disappeared in water. Then she added lemon juice which also gets mixed well in the water to make delicious nimbu paani.

Based on the information answer the following questions:

a. Why did sugar and salt disappear in water?

b. Why do you think we drink nimbu paani in summer?

c. Name two other substances that do not dissolve in water.

Riya went to a restaurant for dinner with her family. In the restaurant she saw beautiful electric switches and she asked her father whether these switches are made up of metals? The electric board and switches fitted at Riya's home looks different from what she saw at the restaurant. 

Riya's father explained to her that all the electric switches/boards are made up of plastic or wood. Why are the electric boards fitted on the wall made of plastic or wood?

Ten-year-old Janavi lives with her parents and two siblings. She is the eldest child of her parents. Last month, her younger brother, who is barely 6 years old, fell ill due to diarrhoea.

Her mother took him to the village dispensary where the doctor handed her few packets of ORS. He advised her to mix the contents in water(1 litre per pack) and give the solution to her brother at regular intervals. This saved the little boy's life.

a) What is the composition of ORS?
(b) Is the ORS solution homogeneous or heterogeneous?

Ravi added some salt into water and found that salt got vanished after sometimes and forms a clear solution. But he found some solids floating over the surface of the water.

Help Ravi to learn about the property of the salt that helped it in getting vanished but some particles remained floating.

Rahul's house is getting painted. The painters asked for some turpentine oil to wipe the paint off their hands and from the floor after finishing their work. Rahul gave them water to clean the paint from their hands and from the floor. The painters said that they needed turpentine oil or kerosene oil for this purpose.
Rahul was surprised to hear it because he has seen that water only is trypically used for washing and cleaning purposes.

Why didn't the painters washed their hands with water instead of turpentine oil?

As the rainy season is around the corner, Ramya went shopping with her father. Her father bought an umbrella for himself, Ramya also asked for an umbrella from her father. Her father advised her to purchase a raincoat instead of umbrella. She liked one woollen coat that was displayed on the mannequin. Her father smiled and said that it is not a raincoat and her father helped her in choosing a raincoat for her.

a) Why Ramya's father said that the woollen coat displayed on the mannequin was not a raincoat?

b) Which material is used to make raincoat?

Ravi was assisting his mother in preparing the dinner. Ravi's mother asked him to bring the vegetables from the refrigerator and wash them properly. Ravi washed the veggetables properly and gave it to her mother. She then cut, sliced and chopped the vegetables with a set of sharp knives. Ravi was fascinated by how quickly she did all this. Now, Ravi want some information regarding knives. Can you help him in answering them?

a) The knife is usually made from which material?

b) What will happen if a knife is completely made of wood? Explain giving reasons.

Rahul's father is building a new house for them. Rahul's father was requested by the carpenter to get nails from the store. Rahul went with his father to the hardware store and purchased some nails. Rahul's father made him hold the carry bag containing nails on the bike. Rahul felt that the nails were very heavy and wished that the nails need to be lightweight to make it easier to carry and transport.

a) Which material is used to make nails?

b) What will happen if nails are made of plastic?