(a) Tabulate the differences in the characterisitcs of states of matter.
(b) Comment upon the following: rigidity, compressibility, fluidity, filling a gas container, shape, kinetic energy and density.
(a) Solid:
* Particles are rigid and un-incompressible.
* Particles possess a definite shape and volume.
* Particles don't have the ability to flow.
* Particles have the least kinetic energy.
* Particles have high density. eg.: salt, iron, gold, chalk.
Liquid:
* Particles are not rigid but can be compressed to a limited extent.
* Particles have only a definite volume but acquire the shape of a container in which they are kept.
* Particles can easily flow from higher to the lower level.
* Particles have more kinetic energy than solid.
* Particles have less density than solids. eg.: water, alcohol, petrol etc.
Gas:
* Particles are not rigid and can be compressed easily.
* Particles don't have a definite shape of volume.
* Particles can flow in all the possible directions.
* Particles have maximum kinetic energy.
* Particles have the least density. eg.: air, CNG, smoke etc.
(b)
* Rigidity: It is the property of matter to maintain its shape even if an external force is applied and the solids show it this property.
* Compressibility: It is the property of matter to allow decrease in volume under high pressure and gases show this property.
* Fluidity: It is the property of a substance to easily flow and allow change in its shape under external forces and this property is shown by both liquids and gases.
* Filling a gas container: Gases can be compressed easily hence they can be filled within a vessel at high pressure. This property of gases allows their convenient filling into a small container or cylinder and that also in a large volume. It also allows their easy transport from one place to other e.g. CNG.
* Shape: According to the type of matter shape differ depending upon the location of particles like solid have a definite shape while liquid acquire the shape of their container and gases as such don't have any shape.
* Kinetic energy: It is the kind of energy present in an object when it is under motion as the particles of that object are continuously moving therefore the object has kinetic energy. However, greater is the movement, more will be the kinetic energy and vise-versa.
Kinetic Energy = Gas > Liquid > Solid
Kinetic energy of gas is maximum.
* Density: Mass per unit volume of a substance is known as its density.
Density = Solid > Liquid > Gas
Solids have the greatest density.
What type of clothes should we wear in summer?
Name A,B,C,D,E and F in the following diagram showing change in its state
Give two reasons to justify—
(a) water at room temperature is a liquid.
(b) an iron almirah is a solid at room temperature.
Give reasons
(a) A gas fills completely the vessel in which it is kept.
(b) A gas exerts pressure on the walls of the container.
(c) A wooden table should be called a solid.
(d) We can easily move our hand in air but to do the same through a solid block of wood we need a karate expert.
Suggest a method to liquefy atmospheric gases.
Give reason for the following observations.
(a) Naphthalene balls disappear with time without leaving any solid.
(b) We can get the smell of perfume sitting several metres away.
Which of the following are matter?
Chair, air, love, smell, hate, almonds, thought, cold, cold-drink, smell of perfume.
The mass per unit volume of a substance is called density. (density = mass/volume). Arrange the following in order of increasing density – air, exhaust from chimneys, honey, water, chalk, cotton and iron.
Give reasons for the following observation:
The smell of hot sizzling food reaches you several metres away, but to get the smell from cold food you have to go close.
Convert the following temperature to celsius scale:
a. 300 K b. 573 K.
Which of the following has more inertia: (a) a rubber ball and a stone of the same size? (b) a bicycle and a train? (c) a five-rupees coin and a one-rupee coin?
State the universal law of gravitation.
A force of 7 N acts on an object. The displacement is, say 8 m, in the direction of the force (Fig. 11.3). Let us take it that the force acts on the object through the displacement. What is the work done in this case?
What is meant by a pure substance?
How does the sound produced by a vibrating object in a medium reach your ear?
In a reaction, 5.3 g of sodium carbonate reacted with 6 g of ethanoic acid. The products were 2.2 g of carbon dioxide, 0.9 g water and 8.2 g of sodium observations are in agreement with the law of conservation of mass.
sodium carbonate + ethanoic acid → sodium ethanoate + carbon dioxide + water
What are canal rays?
State any two conditions essential for good health.
How is our atmosphere different from the atmospheres on Venus and Mars?
Who discovered cells, and how?
An athlete completes one round of a circular track of diameter 200 m in 40 s. What will be the distance covered and the displacement at the end of 2 minutes 20 s?
A farmer moves along the boundary of a square field of side 10 m in 40 s. What will be the magnitude of displacement of the farmer at the end of 2 minutes 20 seconds?
Diagrammatically show the difference between the three types of muscle fibres.
Carry out the following osmosis experiment:
Take four peeled potato halves and scoos each one out to make potato cups. One of these potato cups should be made from a boiled potato. Put each potato cup in a trough containing water. Now,
(a) Keep cup A empty
(b) Put one teaspoon sugar in cup B
(c) Put one teaspoon salt in cup C
(d) Put one teaspoon sugar in the boiled potato cup D.
Keep these for two hours. Then observe the four potato cups and answer the following:
(i) Explain why water gathers in the hollowed portion of B and C.
(ii) Why is potato A necessary for this experiment?
(iii) Explain why water does not gather in the hollowed out portions of A and D.
During an experiment, a signal from a spaceship reached the ground station in five minutes. What was the distance of the spaceship from the ground station? The signal travels at the speed of light, that is, 3 × 108 m s-1.
Compare all the proposed models of an atom given in this chapter.
Rutherford’s alpha-particle scattering experiment was responsible for the discovery of
(a) Atomic Nucleus (b) Electron
(c) Proton (d) Neutron
The average atomic mass of a sample of an element X is 16.2 u. What are the percentages of isotopes 168 X and 188 X in the sample?
An object experiences a net zero external unbalanced force. Is it possible for the object to be travelling with a non-zero velocity? If yes, state the conditions that must be placed on the magnitude and direction of the velocity. If no, provide a reason.
How do plants get nutrients?