Will a leaf taken from a potted plant kept in a dark room for a few days turn blue black when tested for starch? Give reasons for your answer.
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Why do silver articles turn black when kept in the open for a few days?
(a) Metals such as silver when attacked by substances around it such as moisture, acids, gases etc, are said to corrode and this phenomenon is called corrosion. (b) The black substance...
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Two green plants are kept separately in oxygen , one in the dark and the other in continuous light. Which one will live longer? Give reasons.
Plant kept in continuous light will live longer, because it will be able to produce oxygen required for its respiration by the process of photosynthesis.
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Leaves of a healthy potted plant were coated with vaseline. Will this plant remain healthy for long? Give reasons for your answer.
The plant will not remain healthy for long and it will die. Vaseline is thick and it will block the stomata so there will be no intake of carbon dioxide. It will...
1 Answers 1 views
There is a black spot on a body. If the body is heated & carried in dark room, then it glows more. This can be explained by:
Correct Answer is C Explanation : According to Kirchhoff's law, a good emitter is also a good absorber.
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Why is the colour of a leaf kept in the dark frequently yellow, or pale green? Which pigment do you think is more stable?
Since leaves require light to perform photosynthesis, the colour of a leaf kept in the dark changes from a darker to a lighter shade of green. Sometimes, it also turns...
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If a potted plant is covered with a glass jar, water vapours appear on the wall of glass jar. Explain why?
Hint—Because of transpiration
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Suppose you are in a dark room. Can you see objects in the room? Can you see objects outside the room? Explain.
We can see any object, when light reflected by that object reaches our eyes. But in the dark room, no light is reflected by the object so we are unable...
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In one room. There was a 10 bulbs every bulb can turn on independently by itself, so how many ways you can glow the room.
Since each light can be switched on independently, there are two options for each bulb (on or off) ∴Total no. of ways the bulbs can be operated= 210 This includes all the bulbs are...
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A silver article generally turns black when kept in open for a few days. The article when rubbed with toothpaste again starts shining.
i. Silver reacts with hydrogen sulphide gas present in air and forms a compound Ag2S. This compound is black in colour. Hence, silver articles turn black when kept in the...
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Leaves of a healthy potted plant were coated with vaseline to block the stomata.
If waxy coating is made on the surface of leaf, loss of water in the form of water vapour does not take place. Even the gaseous exchange will not take...
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