A model used to explain the behavior of matter and how it affects the physical and properties of materials
Matter
Made up of tiny particles that are constantly in motion
Energy varies depending on the temperature of the substance
States of matter
Solids
Liquids
Gases
Solids
Least amount of energy, particles kept tightly packed together, only vibrate
Liquids
Move a bit and flow, have more space in between matter than solids, less than gases
Gases
Most space between them, easily the most compressible
Temperature of a substance
Directly proportional to the average kinetic energy of its particles
Higher temperature, higher kinetic energy, lower temperature, lower energy
Spaces between molecules
Solids have smaller spaces than gases, liquids have bigger spaces than solids but smaller than gases, gases have the most amount of empty space
Phase change
1. Sufficient change in temperature
2. Intermolecular forces of attraction weaken
Higher temperature
Lower intermolecular forces of attraction
Lower temperature
Higher intermolecular forces of attraction
Sufficient heat applied to a substance weakens its intermolecular forces of attraction, causing particles to pull away from each other (e.g. ice to water)
Intermolecular forces
Forces that hold the particles together, strength increases as distance between particles decreases
Temperature
Directly proportional to intermolecular forces, as temperature increases kinetic energy increases and intermolecular forces decrease
Matter is made of particles that are constantly in motion, this energy in motion is called kinetic energy
The amount of kinetic energy in a substance is related to its temperature
There is space between particles, the amount of space is related to the substance's state of matter
Phase changes happen when the temperature of the substance changes sufficiently
There are attractive forces between particles called intermolecular forces
The strength of intermolecular forces increases as particles get closer together
Intermolecular forces
Attractive forces that act between molecules or particles in the solid or liquid states, generally weaker than bonding forces
Types of intermolecular forces
Dipole-dipole
Ion-dipole force
Dispersion forces
Hydrogen bonds
Properties of liquids
Fluid and can flow, have definite volume but no definite shape, low compressibility, little space between particles
Liquids
Have more kinetic energy than solids, thus having less intermolecular forces
Properties of solids
Don't flow, have definite shape and volume, little kinetic energy and vibrate in place, usually arranged in a tightly packed crystalline structure
Types of solids
Ionic solids
Molecular solids
Covalent network solids
Metallic solids
Stoichiometry
The study of the quantitative aspects of chemical reactions, deals with the numerical relationships of elements and compounds and the mathematical proportions of reactants and products in chemical transformations