Students can Download Chapter 6 Changes Around Us Questions and Answers, Notes Pdf, KSEEB Solutions for Class 6 Science, Karnataka State Board Solutions help you to revise complete Syllabus and score more marks in your examinations.
Karnataka State Syllabus Class 6 Science Chapter 6 Changes Around Us
Class 6 Science Changes Around Us NCERT Textbook Questions and Answers
Question 1.
To walk through a water logged area, you usually shorten the length of your dress by folding it. Can this change be reversed?
Answer:
Yes, this change is reversible and it can be done by unfolding the pants.
Question 2.
You accidentally dropped your favourite toy and broke it. This is a change you did not want. Can this change be reserved?
Answer:
No, this change (Breaking of Barbie doll) cannot be reversed.
Question 3.
Some changes are listed in the following table, For each changes, write in the blank column, whether the change can be reversed or not.
Answer:
Sl no | change | can be reversed Yes / No |
1. | The sawing of a piece of wood | Yes |
2. | The melting of ice candy | Yes |
3. | Dissolving sugar in water | No |
4. | The cooking of food | No |
5. | The ripening of a mango | No |
6. | Souring of milk | No |
Question 4.
A drawing sheet changes when you draw a picture on it. Can you reverse this change?
Answer:
No, we cannot get fresh drawing sheet once a picture is drawn on it with paint/oil or water. However, we can reverse the change, if soft pencil is used to draw the picture.
Question 5.
Give examples to explain the difference between changes that can or cannot be reversed.
Answer:
Examples of reversible and irreversible changes
Question 6.
A thick coating of a paste of plaster of Pans (POP) is applied over the bandage on a fractured bone. It becomes hard on drying, to keep the fractured bone immobilised. Can the change in POP be reversed?
Answer:
No, the change in POP cannot be reversed since it is a chemical change.
Question 7.
A bag of cement lying in the open gets wet due to rain during the night. The next day the sun shines brightly. Do you think the changes, which have occured in the cement, could be reversed ?
Answer:
No, these are irreversible chemical changes.
Class 6 Science Changes Around Us Additional Important Questions and Answers
I. Choose the correct answer:
Question 1.
Baking of dough into bread is a kind of change.
a) That can be reversed
b) That cannot be reversed
c) That can be reversed art very temperature
d) Can’t say
Answer:
b) That cannot be reversed
Question 2.
Which of the following is a reversible change
a) Curdling of milk
b) Ripening of fruits
c) Melting of ice
d) Burning of wood
Answer:
c) Melting of ice
Question 3.
Which of the following is a desirable change ?
a) Burning of house
b) Floods
c) Land slides
d) Burning of cooking gas
Answer:
d) Burning of cooking gas
Question 4.
Change in which heat is liberated are called ____
a) Exothermic changes
b) Endothermic changes
c) Rapid changes
d) None of these
Answer:
a) Exothermic changes
Question 5.
Which of the following can be considered as fast change.
a) Growth of child
b) Germination of seed
c) Burning of crackers
d) Cooking of food.
Answer:
c) Burning of crackers
II. Answer the following
Question 1.
Give two examples of slow changes
Answer:
a) Growing of plants
b) Ripening of fruits
Question 2.
Give two examples of fast changes
Answer:
a) Blowing of balloon
b) Rolling out roti from dough ball
Question 3.
Give two examples of reversible changes.
Answer:
a) Drying a wet clothes
b) Heating of milk
Question 4.
Give two examples of irreversible changes.
Answer:
a) Milk to cheese
b) Cooking of food
Question 5.
Can you say deforestation is an irreversible or reversible change.
Answer:
It is an irreversible changes.
Question 6.
Write some changes happening in our body
Answer:
a) Our nails grow
b) Our hair grow
c) We grow taller
d) Our weight increases
Question 7.
What is a physical change ? Explain with example.
Answer:
The changes in which only physical properties of substances is formed is called physical change. It is a reversible change. Ex:- Boiling and freezing of water.
Question 8.
What is a chemical change ? Explain with example.
Answer:
The changes in which new substances with new chemical properties are formed are called chemical changes.
Ex:- Reaction between washing soda and lemon juice in which CO2 and other substance are formed.
Question 9.
What happens when sugar is heated?
Answer:
When sugar is heated continuously then a black powdery substance is formed. This is a chemical change.
Question 10.
Explain how a metal rim slightly smaller than a wooden wheel can be fixed on it.
Answer:
The metal rim is always made slightly smaller than the wooden wheel. The metal rim is heated on heating the rim expands and fit onto the wheel. Cold water is then poured over the rim due to cooling the metal rim contracts and fits tightly onto the wooden wheel
III. Classify the following into slow and fast changes:-