C1.1 Flashcards
Gases
Gas particles are in random arrangement and are very far apart. The particles move very quickly in all directions.
Liquids
Particles of a liquid are in random arrangement and they move around each other. They are close together.
Solids
Particles of a substance in the solid state are in regular arrangement and the relative distance between the particles is very close. Their movement consists of vibrating around a fixed position.
What state(s) can you bot compress?
You cannot compress a substance in its liquid and liquid state as their particles do not have enough space to move into.
Why can’t solids flow?
A substance in its liquid state cannot flow and is in a fixed shape. This is because its particles vibrate around fixed positions and cannot move from place to place.
Particle
Everything is made up of matter and a particle is a tiny bit of matter.
The particle model
The particle model describes the movement and arrangement of particles in solids, liquids and gases. The particle model also explains why some properties of a substance depends on its state.
Limitations of the particle model
The particle model does not show the exact size of each particle and the exact distance between each particle. Also it doesn’t show the forces between the particles.
Types of particles
Atoms: smallest form of a particle
Molecule: two or more atoms joined together
Ion: a charged particle, negatively or positively. Formed when an atoms loses or gains electron (which can happen in chemical reactions, like sodium and oxygen)
Chemical change
In a chemical change one or more new substances are formed. The properties of the new substances are usually different to the original substances. Chemical changes are very difficult or impossible to reverse.
Physical chnages
In physical changes no new substances are made. In physical changes, substances either change state, or shape or break into pieces. Majority of physical changes are reversible.
What happens when a substance changes state?
When a substance changes state its particles remain the same but their arrangement and movement change.
What happens to particles in chemical reactions?
In chemical reactions a substance’s particles break apart and then join together in different ways. This how new substabces are made.
Electrostatic forces
Forces of attraction or repulsion between electrically charged particles
Isotpes
Isotopes of an element are atoms with the same amount of electrons and protons but a different number of neutrons.
