Matter in Our Surroundings
Matter is defined as anything that occupies space and has mass. Everything around us, whether it be air, solid rocks, water, or living organisms, consists of matter. It can be classified based on its physical properties into three main states: solids, liquids, and gases.
1.1 Physical Nature of Matter
1.1.1 Matter is Made Up of Particles: Matter can either be continuous or particulate. This can be demonstrated through activities involving the dissolution of substances like salt or sugar in water — where we see that even after dissolving, the matter has particles that spread throughout the water without changing the water's volume.
1.1.2 How Small Are These Particles of Matter?: The size of particles is incredibly small, as demonstrated through dilutions of colored solutions. Even a few crystals can color a large volume of water, implying that particles are present in millions even in small amounts.
1.2 Characteristics of Particles of Matter
Particles possess kinetic energy and are in constant motion, which is affected by temperature — they move faster when heated. They also attract each other, and the strength of this attraction varies between different types of matter. The activities illustrate how particles intermingle and diffuse into one another, confirming their continuous movement.
1.3 States of Matter
Matter exists in three states:
- Solid: Has a definite shape and volume with particles tightly packed.
- Liquid: Has a definite volume but takes the shape of the container with loosely packed particles.
- Gas: Has neither definite shape nor volume with particles that are far apart and move freely.
1.4 Can Matter Change its State?
Matter can change its state through changes in temperature and pressure. For example, water can exist as ice (solid), water (liquid), and steam (gas). Sublimation is the transition of a solid directly to a gas, while deposition reverses this process.
Key Takeaway
The study of matter and its principles is fundamental in understanding the physical world and phenomena around us.