Can we reverse the following change? If yes, suggest the name of the method.
Water vapour into water
[6] Changes Around Us
Chapter: [6] Changes Around Us
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Can we reverse the following change? If yes, suggest the name of the method.
Ice into water
[6] Changes Around Us
Chapter: [6] Changes Around Us
Concept: undefined >> undefined
Can we reverse the following change? If yes, suggest the name of the method.
Curd into milk
[6] Changes Around Us
Chapter: [6] Changes Around Us
Concept: undefined >> undefined
Which of the following changes cannot be reversed?
- Blowing of a balloon
- Folding paper to make a toy aeroplane
- Rolling a ball of dough to make roti
- Baking cake in an oven
- Drying a wet cloth
- Making biogas from cow dung
- Burning of a candle
[6] Changes Around Us
Chapter: [6] Changes Around Us
Concept: undefined >> undefined
Boojho’s sister broke a white dove, a symbol of peace, made of Plaster of Paris (POP). Boojho tried to reconstruct the toy by making a powder of the broken pieces and then making a paste by mixing water. Will he be successful in his effort? Justify your answer.
[6] Changes Around Us
Chapter: [6] Changes Around Us
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Tearing of paper is said to be a change that cannot be reversed. What about paper recycling?
[6] Changes Around Us
Chapter: [6] Changes Around Us
Concept: undefined >> undefined
Give one example of change which occurs on heating but can be reversed.
[6] Changes Around Us
Chapter: [6] Changes Around Us
Concept: undefined >> undefined
Give one example of change which occurs on heating but cannot be reversed.
[6] Changes Around Us
Chapter: [6] Changes Around Us
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Give one example of change which occurs on cooling but can be reversed.
[6] Changes Around Us
Chapter: [6] Changes Around Us
Concept: undefined >> undefined
Give one example of change occurs on mixing two substances, but can be reversed.
[6] Changes Around Us
Chapter: [6] Changes Around Us
Concept: undefined >> undefined
Give one example of change which occurs on mixing two substances, but cannot be reversed.
[6] Changes Around Us
Chapter: [6] Changes Around Us
Concept: undefined >> undefined
A potter working on his wheel shaped a lump of clay into a pot. He then baked the pot in an oven. Do these two acts lead to the same kind of changes or different? Give your opinion and justify your answer.
[6] Changes Around Us
Chapter: [6] Changes Around Us
Concept: undefined >> undefined
Conversion of ice into water and water into ice is an example of change which can be reversed. Give four more examples where you can say that the changes can be reversed.
[6] Changes Around Us
Chapter: [6] Changes Around Us
Concept: undefined >> undefined
Change of a bud into a flower is a change which cannot be reversed. Give four more such example.
[6] Changes Around Us
Chapter: [6] Changes Around Us
Concept: undefined >> undefined
Paheli mixed flour and water and
- made a dough,
- rolled the dough to make a chapati,
- baked the chapati on a pan,
- dried the chapati and ground it in a grinder to make powder.
Identify the changes (i) to (iv) as the changes that can be reversed or that cannot be reversed.
[6] Changes Around Us
Chapter: [6] Changes Around Us
Concept: undefined >> undefined
lt was Paheli’s birthday, her brother Simba was helping her to decorate the house for the birthday party and their parents were also busy making other arrangements. Following were the activities going on at Paheli’s home:
- Simba blew balloons and put them on the wall.
- Some of the balloons got burst.
- Paheli cut colourful strips of paper and put them on the wall with the help of tape.
- She also made some flowers by origami (paper folding) to decorate the house.
- Her father made dough balls.
Mother rolled the dough balls to make puries.
- Mother heated oil in a pan.
- Father fried the puries in hot oil.
Identify the activities at Paheli’s home as those that can be reversed and those which cannot be reversed.
[6] Changes Around Us
Chapter: [6] Changes Around Us
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Which of the following terms constitute the female part of the flower?
[4] Getting to Know Plants
Chapter: [4] Getting to Know Plants
Concept: undefined >> undefined
Figure shows a measuring scale which is usually supplied with a geometry box. Which of the following distance cannot be measured with this scale by using it only once?
[7] Motion and Measurement of Distances
Chapter: [7] Motion and Measurement of Distances
Concept: undefined >> undefined
A piece of ribbon folded five times is placed along a 30 cm long measuring scale as shown in the following figure.
The length of the ribbon is between
[7] Motion and Measurement of Distances
Chapter: [7] Motion and Measurement of Distances
Concept: undefined >> undefined
Read the function of parts of a plant given below:
- Fixes plant to the soil
- Prepares starch
- Takes part in reproduction
- Supports branches and bears flowers
In the diagram given in the following figure, write the names of the parts whose functions you have just read at the appropriate space.
[4] Getting to Know Plants
Chapter: [4] Getting to Know Plants
Concept: undefined >> undefined
