Diffusion
Trending Questions
Explain the following :
When an incense stick is lighted in the corner of a room, its fragrance spreads quickly in the entire room.
When a crystal of potassium permanganate is placed at the bottom of the water in a beaker, the water in the whole beaker turns purple on its own, even without stirring. This is an example of :
(a) distribution (b) intrusion (c) diffusion (d) effusion
Explain how, the smell of food being cooked in the kitchen reaches us even from a considerable distance.
Explain why, diffusion occurs more quickly in a gas than a liquid.
Why is the smell of the perfume of incense stick filled the whole room in few minutes, when lighted ?
Give one example of the diffusion of a solid in another solid.
When a gas jar containing air is inverted over a gas jar containing bromine vapour, the red-brown bromine vapour diffuse into air. Explain how bromine vapour diffuse into air.
As we increase the temperature, the rate of diffusion _________.
Does not change.
Decreases
Increases
First decreases and then increases.
A bottle of perfume was opened in a room . The smell of its vapours spread in the entire room. Name the property of gases which responsible for this behaviour of perfume vapours.
What is the effect of temperature on the rate of diffusion?
Explain why, the diffusion of a solid in another solid is a very slow process.
Look at the diagram on the right side.Jar A contains a red -brown gas whereas jar B contains a colourless gas. The two gas jars separated by a glass plate placed between them
(a) What will happen when the glass plate between the two jars is pulled away ?
(b What name is givnen to the phenomenon which takes place ?
(c Name the brown gas which could be in jar A.
(d Which is the colourless gas most likely to be present in jar B?
(e) Name one coloured solid and one colourless liquid which can show the same phenomenon.
Bromine and air take about 15 minutes to diffuse completely but bromine diffuses into a vacuum very rapidly. Why is this so ?
Which of the two diffuses faster : a liquid or a gas ?
The smell of hot food reaches us more quickly as compared to smell of cold food. Why?
Can solids diffuse like liquids and gas?
(a) What is meant by 'diffusion'? Give one example of diffusion in gases.
(b) Why do gases diffuse very fast?
(c) Name two gases of air which dissolve in water by diffusion. What is the importance of this process in nature?
Name the property of gases that help aquatic plants and animals to survive in the water?
Explain why, osmosis can be considerd to be a special kind of diffusion. Classify the following into
(i) osmosis, and (ii) diffusion:
(a) swelling up of a raisin on keeping in water
(b) spreading of virus on sneezing
(c) earth worm dying on coming in contact with common salt
(d) shrinking of grapes kept in thick sugar syrup
(e) preserving of pickles in salt
(f) spreading of smell of cake being baked in the kitchen
(g) aquatic animals using oxygen dissolved in water during respiration
Bromine particles are almost twice as heavy as chlorine particles.Which gas will diffuse faster; bromine (vapour) or chlorine ? Explain your answer.
A student placed a gas jar containing air in the upside down position over a gas jar full of red-brown bromne vapours. He observed that the red-brown colour spread upwards into the jar containing air. Based on this observation, the student concluded that it 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.
When a gas jar full the lower jar go upward into the jar containing air. In this experiment :
(a) air is heavier than bromine
(b) both air and bromine have the same density
(c) bromine is heavier than air
(d) bromine cannot be heavier than air because it is going upwards against gravity
(a) What does the diffusion of gases tell us about their particles ?
(b) Give one example of diffusion of gases in a liquid.
- perfume molecules move from high concentration area to low concentration area.
- perfume molecules spread through gaps between the air particles
- they diffuse.
- they are carried by the person who opens the bottle.
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?
(a) bromine vapour is made of tiny paricles which are moving
(b) air is made up of tiny particles which are moving
(c) the paricles of bromine are moving but those of air not moving
(d) even though bromine vapour is heavier than air, it can move up against gravity
Name one property of liquids and gases which tells us that therir molecules are moving constantly.
Which of the following diffuses fastest and which the slowest ?
Solid. Liquid, Gas
Name two processes which provide the best evidence for the motion of particles in matter.
