Pure Substances, mixtures and seperations Flashcards
What is a pure substance?
A pure substance consists of a single type of material only.
What can matter be classified in?
Pure substances and mixtures
What can pure substances be classified in?
Elements and compund
What can mixtures be classified in?
Homogenous and heterogenous
What are the characteristics of pure substances?
- Its composition is fixed and constant
- The properties are fixed and constant for example density, boiling point, melting point.
- The component parts cannot be seperated by any physical process.
What is an element?
An element is a pure substance that cannot be broken down into simpler substances by using any physical or chemical process.
Elements can be classified in what?
Metals and non-metals
What is a compound?
A compound is a pure substance that is formed from two or more different elements that are chemically bonded together in fixed propotions in a way that their properties have changed.
What is a mixture?
A mixture is a composed of 2 or more substances which are physically combined in variable proportions.
What are the characteristics of mixtures?
- its composition can vary
- Its properties are variable because each part keep their individual properties
- Components can be seperated by physical means
What is a homogenous mixture?
A uniform mixture and the particles cannot be seen with the naked eye or be seperated physically. Solutions are homogenous
What is a heterogenous mixture?
Non uniform mixture. It is possible to distinguish the components part from each other though not always with the naked eye. The components can be sepertated physically. They incude colloids and suspensions.
What is a solution?
A homogenous mixture with 2 or more substances. 1 substance is usually a liquid.
What is a the solution composed of?
Solvent- The substance that does the dissolving
Solute- the substance that is being dissolved
