Enter your Sign-on user name and password.

Forgot password?
  • Follow us on:
Loading video...

Start Learning Now

Our free lessons will get you started (Flash® 10 required).
Get immediate access to our entire library.

Sign up for Educator.com

Features Overview

  • Get on-demand access to our complete library
  • Search and jump to exactly what you need to learn
  • Track your progress
  • Download practice and lesson files
  • *Ask questions and get answers from our community & instructors

Atomic Theory and Measurement

  • Dalton’s Atomic Theory: statements which shaped atomic theory for years; atoms cannot be cut, atoms of one element are identical, compounds are made from small numbers of atoms

  • Law of Multiple Proportions: definition

  • Current Atomic Theory: atoms have components (protons, electrons, neutrons); atoms of same element may have different masses (isotopes)

  • Nuclear charge Z is an integer and identifies an element

  • Atomic Masses are in amu, isotopes have different number of neutrons

  • Learn the basic SI units and multipliers

Atomic Theory and Measurement

Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.

Advanced Placement Chemistry