मराठी

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

प्रश्न

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.

औचित्य

उत्तर

Boojho will not be successful because making of toy from Plaster of Paris (POP) is an irreversible change. Once the Plaster of Paris is mixed with water and dried it cannot regain its properties.

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Classification of Change: Reversible and Irreversible Changes

या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?

Q 13.Q 12.Q 14.

पाठ 6: Changes Around Us - Short Answer Questions [पृष्ठ ३५]

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एनसीईआरटी एक्झांप्लर Science [English] Class 6

पाठ 6 Changes Around Us
Short Answer Questions | Q 13. | पृष्ठ ३५

संबंधित प्रश्‍न

Very Short Answer Type Question:
Some common changes are given in the below Table. Which of these changes do you think can be reversed?

Change	Can be reversed
(i) Raw egg to boiled egg	Yes/No
(ii) Batter to idli
(iii) Wet clothes to dirty clothes
(iv) Woollen yarn to knitted sweater
(v) Grain to its flour
(vi) Cold milk to hot milk
(vii) straight string to a cold string
(viii) Bud to flower
(ix) Milk to paneer
(x) Cow dung to biogas
(xi) stretched rubber band to its normal size
(xii) Melting of ice-cream

An example for reversible change is

When a candle is lit the following changes are observed.

Wax melts.
Candle keeps burning.
The size of the candle decreases.
The molten wax solidifies
Which of the changes can be reversed? Justify your answer

When ‘Touch me not’ plant is touched by us, ______ changes occur.

Analogy:

Irreversible change: Making idly front batter.
Reversible change: ______.

Salt can be separated from its solution (salt dissolved in water), because ______.

Give one example of change which occurs on heating but can be reversed.

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.

Circle the odd one out. Give reason for your choice.

Select the odd one out. Give reason for your the choice