You may improve this article, discuss the issue on the talk page, or create a new article, as appropriate. (January 2015) The history of economic thought deals with different thinkers and theories in the subject that became political economy and economics, from the ancient world to the present day. It encompasses many disparate schools of economic thought.
A pure substance is a substance that cannot be separated by physical means. eg. filtration, evaporation, distillation or chromatography. Examples of pure substances include water, gold, glucose, carbon dioxide, oxygen and hydrogen. A pure substance is made up of one type of particle. The particle that makes up water is H 2 O. The particle that makes up carbon dioxide is CO 2.
Unit 3 Elements Made up of only one type of particle called an Atom. Any substance that is made up of one type of particle is called a pure substance.An element cannot be separated into simpler substances by chemical or physical means Gold (Au) is an element.Each particle is the same.ame_________________ Period________________ Fill in the blank: 1. A pure substance is a substance that contains only one type of ___________________. 2. Characteristic properties can be used to ____________substances.