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प्रश्न
When a gas jar containing colourless air is kept upside down over a gas jar full of brown-coloured bromine vapour, then after some time, the brown colour of bromine vapour spreads into the upper gas jar making both the gas jars appear brown in colour. Which of the following conclusion obtained from these observations is incorrect?
पर्याय
bromine vapour is made of tiny particles which are moving
air is made up of tiny particles which are moving
the particles of bromine are moving but those of air are not moving
even though bromine vapour is heavier that air, it can move up against gravity
उत्तर
The particles of bromine are moving but those of air are not moving
The statement that the particles of bromine are moving but those of air are not moving is incorrect because the particles of matter are constantly in motion. It appears as if the air molecules are not moving because air is colourless.
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संबंधित प्रश्न
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rigidity, compressibility, fluidity, filling a gas container, shape, kinetic energy and density.
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Explain how, the smell of food being cooked in the kitchen reaches us even from a considerable distance.
Explain why, when a bottle of perfume is opened in a room, we can smell it even from a considerable distance.
A student placed a gas jar containing air in the upside down position over a gas jar full of red-brown bromine vapours. He observed that the red-brown colour spread upwards into the jar containing air. Based on this observation, the student concluded that it is only the bromine vapour which moves up and diffuses into air in the upper jar, the air from the upper jar does not move down by diffusion into the lower jar containing bromine vapours. Do you agree with this conclusion of the student? Give reason for your answer.
The substance X normally exists in a physical state which can flow easily but does not fill its vessel completely. It also turns anhydrous copper sulphate blue. When substance X is cooled excessively, it changes into a substance Y which has a fixed shape as well as a fixed volume. If, however, the substance X is heated strongly, it changes into a substance Z which has neither a fixed shape nor a fixed volume.
- Name the substances (i) X (ii) Y and (iii) Z.
- What is the process of conversion of X into Y known as ?
- At which temperature X gets converted into Y ?
- What is the process of conversion of X into Z known as ?
- At which temperature X gets converted into Z ?
The space between ______ particles is the greatest one.
______ is not affected by gravity.
