Chemistry 1302A/B Chapter 1: Chemistry Chapter 1

• School: Western University
• Department: Chemistry
• Course: Chemistry 1302A/B
• Professor: Ken Yeung

Document Summary

Atom is comprised of three main components: protons, neutrons and electrons. Protons and neutrons are found in the nucleus of the atom and as a result the majority of the mass of the atom is found in the nucleus. In the mid-19th century, physicists discovered that when hydrogen gas was placed in a tube and excited, it would dissociate into hydrogen atoms and the excited atoms would emit discrete colours of visible light. Normal energy of an atom= ground state. When electrons fall back down from the excited state to the ground state, they emit energy as light. Every element will give you a different line spectrum. Electromagnetic spectrum: describes the complete range of electromagnetic radiation that travels through space as energy in the form of oscillating waves. Most important types of waves are infrared, visible and uv. Wavelength: refers to the distance between two identical points on adjacent waves (measured in nm nm=1. 0x10-9m) .