23-04-2014, 03:08 PM
matter in our surrounding
surrounding.pptx (Size: 886 KB / Downloads: 26)
INTRODUCTION
As we look at our surroundings, we a large variety of things with different shapes ,sizes and textures. Everything in the universe is made up of material which scientists have named “matter”. The air we breath, the food we eat , stones, clouds, stars, plants and animals, even a small drop of water or a particle of sand – everything is matter. Humans have been trying to understand their surroundings.
PHYSICAL NATURE OF MATTER
For a long time, two schools of thought prevailed regarding the nature of matter. One school believed matter to be continuous like a block of wood, whereas, the other thought that matter was made up of particles like sand. Let us perform an activity to decide about the nature of matter – is it continuous or particulate ?
Characteristics of particles of matter
1) The particles of matter are very, very small.
2) The particles of matter have space between them.
3) The particles of matter are constantly moving.
4) The particles of matter attract each other.
diffusion
The spreading out and mixing of a substance due to the motion of its particles is called diffusion. Diffusion is one substance to another substance goes on until a uniformed mixture is formed.
sublimation
The changing of solid directly into vapours on heating, and of vapours into solid on cooling, is known as sublimation. The solid substance which undergoes sublimation is said to be “sublime”. The solid obtain by cooling the vapours of solid is called a “sublimate”.
surrounding.pptx (Size: 886 KB / Downloads: 26)
INTRODUCTION
As we look at our surroundings, we a large variety of things with different shapes ,sizes and textures. Everything in the universe is made up of material which scientists have named “matter”. The air we breath, the food we eat , stones, clouds, stars, plants and animals, even a small drop of water or a particle of sand – everything is matter. Humans have been trying to understand their surroundings.
PHYSICAL NATURE OF MATTER
For a long time, two schools of thought prevailed regarding the nature of matter. One school believed matter to be continuous like a block of wood, whereas, the other thought that matter was made up of particles like sand. Let us perform an activity to decide about the nature of matter – is it continuous or particulate ?
Characteristics of particles of matter
1) The particles of matter are very, very small.
2) The particles of matter have space between them.
3) The particles of matter are constantly moving.
4) The particles of matter attract each other.
diffusion
The spreading out and mixing of a substance due to the motion of its particles is called diffusion. Diffusion is one substance to another substance goes on until a uniformed mixture is formed.
sublimation
The changing of solid directly into vapours on heating, and of vapours into solid on cooling, is known as sublimation. The solid substance which undergoes sublimation is said to be “sublime”. The solid obtain by cooling the vapours of solid is called a “sublimate”.