Some basic concepts in chemistry:-

MatteràIts anything that occupies space, possesses mass and can be felt by any one or more of our senses.

On the basis of physical classification of matter its of 3 types:-

1. Solid:- which possesses definite shape and definite volume.
2. Liquid:- which possesses definite volume but not definite shape. Eq. milk, oil, alc. Etc.
3. Gases:- which possesses neither definite shape, nor definite volume. Eq. oxygen, nitrogen etc.

( vapours are the gaseous state of substance which is liquid at room temp.)

On the basis of chemical classification matter is of 2 types:-

1. Pure substances:- A single substance which can’t be separated into other kind of matter by any physical process. There are of 2 types:-

1. Elements:- the simplest form of a pure substance which can’t be further broken into simple substance by physical or chemical means. There are of 3 types:- metals (eq. Fe, Cu, Au etc.), non-metals (C, S, Si, N etc.), metalloids (As, Zn, Sb etc.).
2. Compounds:- it’s a substance made up of 2 or more elements. Combined together in fixed proportion by wt. and by chemical methods. Its decomposed to its elements eg. NaCl, H₂O, CO₂ etc compound can be inorganic or organic.

2. Mixtures:- When 2 or more elements or compounds mixed together in any proportion which don’t react together and can be separated by physical means and chemical means eg. 22 carat gold etc. mixtures of 2 types:-

1. Homogenous:- if composition of substances is same throughout eg. 22 carat gold, brass, steel, gasoline, air, milk.
2. Heterogeneous:- if composition of substances is not same throughout eg. Iodized table salt.