First Chapter
The states and transformation of matter
-when you will complete reading this chapter you may learn about following things
# States of matter.
# What is matter?
# Classification of matter.
# Convert of matter.
# Physical change of matter.
# Chemical change of matter.
1.1 Matter
In the world what we see or feel, all the things can be divided in two parts, these are matter and energy. What have mass, what occupy space and what hamper to change its static or mobile states is called matter.
On the other hand what have inertia is called matter. All the things around us are matter. Table, chair, soil, water, air etc are matter. We can’t see air but we can feel the reality of air, it has mass it occupy space. So air is matter
1.2 States of matter
Matter is three kinds such as
(1) Solid, (2) liquid, (3) gas.
(1) Solid : solid matters have a fixed dimension, size and some strength. You can’t change the dimension or size of solid matters easily. You can’t break solid matter by applying a little force. So solid matters have strength. Different matters have different strength. Different metals, hills, solt, sand etc are the example of solid matters. Molecules of solid matters stand near by to each other and a fixed place.
(2) Liquid : liquid matters have a fixed dimension, but have no size. If you keep liquid matters into a pot, liquid matter’s size will be changed as like the pot, but dimension will not be changed. Molecules of liquid matters stand near by to each other. But their gravitation is not as forceful as solid matters. Molecules of liquid matters can change their place, so they have no size. Water, petrol, kerosene, soabin oil are the example of liquid matters.
(3) Gas : Gas matters have no dimension and size. If you keep some gas in a jar, gas will occupy whole place in the jar. But gas’s mass aren’t changed in the different jar. The distance among the molecules of gas is very high, so their gravitation rate is low. The molecules of gas cane move any place easily. Nitrogen, oxygen, hydrogen, carbon-dioxide etc are the example of gas matters.
1.3 Transformation of matter
Generally, a matter can stand in three different states such as ice, water and steam are same mater. In normally temperature water is a liquid matter. If you refrigerate the water with 00C, water will be turned into ice. If you heat the ice it will be changed into water again. If you heat water with 1000 C, it will be turned into steam. Again refrigerate the steam; it will be turned into water. In this way you can melt all solid matters into liquid matters. In which temperature solid matters melt into liquid; this called the melting point of the solid matters.
By heating more the liquid matters; it wll being changed into steam and become boiling. In which temperature liquid matters start to boil is called Boiling point of the liquid matters. You can see the following method.
Refrigerate Heat
Solid → liquid ← Gas
← →
But if you heat some solid matters such as Iodine, this will be changed into steam directly and this is called Sublimation.
1.4 Intermolecular forces
There have a question how does a matter stand in three states and why this states depends on temperature? Any matter is made by very small mote. Mote is called molecule. Molecules attract to each other. Such as in water or ice; molecules attract to each other, so they stand together. This attraction is called Intermolecular Forces.
Molecules want to stand near to each other for intermolecular force. Molecules are always being vibrated. You can increase vibration by increasing temperature. For heat energy molecules get motion, as a result molecules want to separate from each other. When intermolecular forces are high from molecule’s dynamic energy then molecules co-exist in a fixed place. And it creates solid states. If you increase the temperature, the vibration energy will go up. As a result molecules can’t co-exist in a fixed place. They start moving. It creates liquid states of matter. If you increase temperature more, molecular motion energy will increase in a high rate. As a result molecules go far away from each other. They can move freely. It creates gas states of matter.
I think you have understood a certain subject that there have very attractions in molecules. To separate them you should give more heat. If the intermolecular forces are high, the melting and boiling point of matter will be very high. Such as general salt’s melting point is 8010C and boiling point is 14650C. On the other hand if molecular forces are low, molecules can separate from each other in a few temperatures. Such as Hydrogen’s molecular force is low so it is gas in general temperature. Water’s melting point is 00C and boiling point is 1000C
1.5 Classification of matter
By elements and composition matters can be divided the following classes.
Matter
↓
. .
↓ ↓
Mixture Pure substance
↓ ↓
, .
↓ ↓ ↓ ↓
Equal mixture Non –equal mixture Element Compound
↓
.
↓ ↓
Metals Non-metals
(1)Mixture: If you admixture two or more matter together in any ratio or proportion and if they can sustain their attribute and stand co-exist it is called mixture. There are two kinds of mixture. Such as (a) Equal mixture and (b) Non-equal mixture.
(a)Equal mixture: Which mixture’s elements inhere at same ratio in the all parts of mixture and you can’t separate these elements’s existence it is called equal mixture. Such as water shake is an equal mixture. In water shake, water and sugar inhere in a fixed ratio and you can’t understand their existence by microscope. Ocean water is the mixture of various salts.
(b)Non-equal mixture: Which mixture’s elements inhere at different ratio in the all parts of mixture and you can separate these elements’s existence and if its elements are showed separate attribute it is called non-equal mixture. The mixture of sand and sugar is a non-equal mixture. If you experiment this mixture, you will see that the ratio of sand and sugar is not same all the parts of mixture. Somewhere is high and somewhere is low. Besides you can understand their existence under a microscope. If you add water in this mixture, sugar will be melted but not sand. So two parts show different attributes.
(2)Pure substance: ‘Pure substance’ is called that matters which matters have a fixed and unchanged composition and a fixed attribute. Pure gold, pure water etc are pure substance. There are two kinds of pure substance. Such as (a) simple matter and (b) compound matter.
(a)Element or simple matter: You can’t change some matters to other matters by analyzing; these matters are called element or simple matters. Gold, copper, iron, hydrogen, nitrogen, oxygen are simple matter. You can’t change it to other matters by analyse. There are two kinds of elements or simple matters such as (i)metals and (ii)Non-metals
(i)Metals: Which matters glisten and are good conductor, these matters are called metals. Copper, gold, iron etc are metals.
(ii)Non-metals: which matters don‘t glisten and insulator, these matters are called non-metals. Nitrogen, oxygen, chlorine etc are non-metals.
(b)Compound matters: You can get more matters by analyzing some matters; these matters are called compound matters. Such as if you analyze water, you will get hydrogen and oxygen. So water is compound matter.
1.6 Changes in Matter
There have two kinds of changes of matter such as (1) physical change and (2) chemical change.
Physical change: By what change of matter, matter’s outward figures are changed but not turn into new matter, it is called physical change of matter.
Example 1: If you refrigerate water, it will be ice. If you heat water, it will be steam. If you heat ice, it will be water. Ice, water and steam are a same matter. So it is physical change.
Example 2: If you create small pieces from big pieces of sugar, it will not produce other matter. If you test the sugar pieces, you will feel that all pieces are sweet equal.
Chemical change: By what change of matter, one or more matters lost their attribute and urn into other new matters, it is called chemical change
Example: If you keep a iron’s piece in air, there will rusty on the iron piece. Rust attribute is fully separate from iron, oxygen and hydrogen’s attributes. So it is chemical change of matter.
1.7 Difference between physical and chemical changes
Physical change | Chemical change |
(1) It doesn’t create new matters | (1) It create new matters |
(2) It changes the physical attribute of matters | (2) It changes the chemical attribute of matters |
(3) It doesn’t change the chemical combinations | (3) It changes the chemical combinations |
(4) This change is not permanent | (4) This change is permanent |
(5) It loses or creates heat | (5) It loses or creates heat |
(6) It doesn’t change the structure of molecules | (6) It change the structure of molecules |
THE END
