A chemical change is a change in which new substances are formed.
A chemical change produces a set of chemicals which is DIFFERENT from the set of chemicals which existed before the change.
In a chemical change, bonds are broken and formed between different atoms. This breaking and forming of bonds takes place when particles of the original materials collide with one another. Chemical change is usually irreversible.
example
- Combustion
- Mixing chemicals
- Rotting of fruit
- Cooking rice
- Explosion of fireworks
- Tarnishing silver
Physical Change
A physical change is a change in the PHASE of a substance, such that no new substance are formed.
A physical change does not change the set of chemicals involved.
A physical change does not change the set of chemicals involved.
A physical change involves a change in physical properties. Physical properties can be observed without changing the composition of matter. Examples of physical properties include: texture, shape, size, color, volume, mass, weight, taste, smell, and density.
example
- Cutting a material such as wood
- Tearing a piece of tin foil
- Breaking glass
- Mixing different solids
No comments:
Post a Comment