RBSE Solutions for Class 5 Environmental Studies Chapter 13 Let’s Play with Water

RBSE Solutions for Class 5 Environmental Studies Chapter 13 Let’s Play with Water is part of RBSE Solutions for Class 5 Environmental Studies. Here we have given Rajasthan Board RBSE Class 5 Environmental Studies Chapter 13 Let’s Play with Water.

 Board RBSE Textbook SIERT, Rajasthan Class Class 5 Subject Environmental Studies Chapter Chapter 13 Chapter Name Let’s Play with Water Number of Questions 48 Category RBSE Solutions

Rajasthan Board RBSE Class 5 Environmental Studies Chapter 13 Let’s Play with Water

Text Book Questions

Observe and write the answers of the following (Page No. 71)

Question 1.
In which glass a very less quantity of the sugar is visible or not visible at all?
The glass in which sugar is stirred with water, there sugar is visible or not visible at all.

Question 2.
Why is the sugar in one glass less soluble?
Because the water is not stirred by adding sugar in the glass.

Question 3.
Wlw is the sugar in another glass, soluble at a faster rate?
When we stir water, the mobility of water molecules increases and as a result the solubility increases.

Observe and answer the following (Page No. 71)

Question 1.
In which glass, the sugar dissolves fast and in which one, the dissolution is slow?
Sugar quickly dissolves in hot water glass and slow in the cold water glass.

Think and write the answer of the following (Page No. 72)

Question 1.
By performing all the above activities (Page No. 72), what have you understood about the solubility of substances? Write in your notebook.
Regarding dissolving the things in the above activities, we realise that things dissolve quickly in hot water than in cold water, and also on stirring the water, the things dissolve quickly.

Points for discussion (Page No. 73)

Question 1.
In the first chance, does the pen sink?
No, the pen does not sink in first chance.

Question 2.
When the pen, its refill and its cap were put into the water separately, which object floats and which sinks?
When the pen, its refill and its cap were put into the water separately, only the empty pen and its cap floats while the refill sinks.

Question 3.
In which condition does the empty pen sink? Try to find out, why did this happen?
The empty pen sinks in inclined position because since water enters the pen, its weight increases.

Observe and answer the following question (Page No. 73)

Question 1.
Does the oil dissolve in water?
Oil does not dissolve in water.

Question 2.
Where do you see the oil in water?
The oil floats in the upper layer of water.

Question 3.
You must have seen oil on the surface of cooked vegetables and pulses. Why does it happen?
Oil is lighter than water and does not dissolve in it. Hence, the oil is seen on the surface of cooked vegetables and pulses.

Points for discussion (Page No. 73)

Question 1.
It is a saying that “friendship should be like milk and water”. Why is it said so?
When milk and water are mixed, together they look like the same colour and shape. So, friends should look similar in the same way and then only friendship can last for long time.

Explore and write the answers of the following (Page No. 74)

Question 1.
Which things weighed in kilogram are brought to your home?
Things weighed in kilogram are brought to my home are vegetables, pulses, besan, rice, wheat flour etc.

Question 2.
Which things measured in litres are brought to your home?
The things which are measured in litres and brought to our home are milk, water, ghee,
oil, buttermilk etc.

Things to do (Page No. 74)

Question 1.
Take 3-4 different empty utensils. Pour water from 1 litre bottle in each of them and observe how many litres of water gets filled in each utensil?

 Name of the utensils How many litres of water gets filled Kadai 1 litre Large bowl 2 litres Pan 1 litre Jug ½ litre Bucket 5 litre

Question 2.
Fill a bucket half with water. Put a pin in the water and see what happens. Now, put the same pin on a piece of newspaper and place it carefully on the surface of water. Watch it for sometime. What happens? You can remove the piece of newspaper with the help of another pin, if you want.
On placing the pin in bucket of water, the pin sinks. When placing the pin on a piece of newspaper and gently laying it on the surface of the water, then, after a while, the paper melts and it sinks in water.

Learnt, understood and now tell (Page No. 74)

Question 1.
Make a table in your notebook and write the names of 10 things for each of the following – things that dissolve in water, float on water and sink in water.

 S.No Things that dissolve in water Things that float on water Things that sink in water 1. Salt Piece of paper Rubber ball 2. Sugar Pen Mobile 3. Dust of sugar Scale Table chair 4. Buttermilk Plastic ball Chair 5. Lemonrice Feather Watch 6. Food colour Plastic bottle Key 7. Soda Paper boat Coin 8. Glucose Sponge Piece of glass 9. Soft drinks Match stick Piece of iron 10. milk oil Piece of copper

Other Important Questions

Objective type Questions

Question 1.
Which of the following floats on water?
(a). Screw
(b). Pin
(c). Key
(d). Cap of a pen
(d). Cap of a pen

Question 2.
Which of the following sinks in water?
(a). Empty plastic bottle
(b). Cap of a pen
(c). Screw
(d). Flower
(c). Screw

Question 3.
Which one is not soluble in water?
(a) Sugar
(b) Salt
(c). Soda
(d). Sand
(c). Soda

Question 4.
Which substance is measured in litres?
(a) Sugar
(b) Salt
(c) Oil
(d) Wheat flour
(d) Wheat flour

Fill in the blanks :

1. We cannot ……… sugar separately in water.But this water becomes sweet in taste. (see / hear)
2. The liquid substances like milk, oil, kerosene etc. are measured in ………. (kg/ litres)
3. The solid substances like wheat, rice re measured in ………. (kg / litres)
4. Empty pen sinks in water in the ……….. position. (straight / inclined)
1. (see)
2. (litres)
3. (kg)
4. (inclined)

State True or False :

Question 1.
Powder of chalk is soluble in water. (Model Paper)
False

Question 2.
Sugar dissolves quickly in hot water.
True

Question 3.
All-pins do not sink in water.
False

Question 4.
The plastic ball does not sink in water.
True

Very Short Answer Type Questions :

Question 1.
Match stick floats or sinks in the water?
Floats

Question 2.
A lemon floats or sinks in saline water?
Floats

Question 3.
What is the unit of measurement of liquid substances?
Litres

Question 4.
Name two substances which are measured in litres.
Milk and oil.

Question 5.
Name two substances which are measured in kg.
Rice and wheat.

Question 6.
How can we separate oil and water from each other?
To separate the oil from water, keep it for a minute without stirring it. After sometime you can separate off the oil from water surface.

Question 7.
Why do we stir the milk after adding sugar to it?
So that the sugar dissolves in the milk.

Question 8.
In which state of milk does the sugar dissolves quickly – cold or hot?
Hot milk.

Question 9.
How should the friendship be?
Like milk and water.

Question 1.
Take a small bottle of glass or plastic, which is transparent. Half fill it with water and put few drops of oil in it. Close the lid. Shake well now. Look what is going on inside. Now move the bottle without stirring. Look what happens? Did the oil dissolve in water? Where do you find the oil?
Oil does not dissolve in water. Oil is also lighter than water and hence floats’ on water.

Question 2.
Why do the sugar dissolve quickly in hot milk than cold water?
Micro particles of hot water are more dynamic than cold water. ‘Due to the high speed of the water molecules, the sugar in the hot water dissolves faster than cold water.

Question 3.
Why does sugar dissolve quickly on stirring it in water?
By stirring sugar in a glass of water, the sugar particles start to rub each other and it quickly dissolves in water.

Question 4.
Put flowers, cap of pen, pin, match stick, pencils, rubber, empty bottles of plastic and a plastic bottle filled with water etc., in water one by one. Write what you see.

 S.No Things that first floats and then sinks in water Things that float on water Things that sink in water 1. Sponge Flower Screw 2. Paper Cap of pen Pin 3. Match stick Eraser 4. Pencil Key 5. Empty plastic bottle Plastic bottle with water

Question 5.
Choose 5 things from given list which are floating and sinking and write them in the given table. (Model Paper)
Stone, pieces of glass, wooden piece, feather, coin, bangle, chalk, pencil, leaf, paper.

 Floating items/things Sinking items/things Feather Stone Paper Piece of glass Pencil Coin Leaf Bangle chalk

Question 6.
Which of the following dissolves in water and do not dissolve in water.
Oil, salt, colour, alum, ghee, wood, milk, sugar, chalk dust, soil particles.

 Things which dissolves in water Things which do not dissolve in water Salt Oil Alum Ghee Milk Wood Sugar Chalk dust colour Soil particles

Question 7.
Which objects float on the surface of water and why?
When an object is inserted into the water, then it should remove equal amount of water as per its volume. If the weight of the water removed by that object’ is more than its weight, then the object floats oh water.
Application : Screw, key, piece of stone, bricks etc. sinks in water whereas match stick, empty plastic bottle, pencil etc. floats on the surface of water.

Essay Type Questions

Question 1.
Sometimes by seeing and sometimes by tasting we tell what is put in dal, vegetables or sweets. Why is it So?