Chapter 03 Notes

Chapter 03 Notes - 1. H 2 0 = 2 (1.008) + 16.00 = molecular...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Mass Relationships in Chemical Reactions Chapter 3 I. Atomic Mass A. Atomic mass- mass of the atom measured in amu 1. 1 amu =1/12 the mass of a C-12 atom. B. Average Atomic Mass 1. When measuring atomic mass, the number used is the average mass which  accounts for naturally-present isotopes of that element 2. Use atomic masses to four significant figures II. Avagadro’s Number A. Mole (mol)- a system of measurement for atoms in chemistry 1. 6.022 x 10 23  of something is Avagadro’s number B. Molar mass- mass of one mol of atoms/molecules of a substance 1. It is the same as the atomic mass C. 1 g = 6.022 x 10 23  amu 1 amu = 1.661 x 10 -24  g III. Molecular Mass A. Molecular mass (molecular weight)- sum of the atomic masses in the molecule
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 1. H 2 0 = 2 (1.008) + 16.00 = molecular mass IV. Mass Spectrometer A. Is used to determine the mass of an atom. B. Electrons are thrown at atoms and when they collide the atoms become positively charged by dislodging an electron. These positively charged atoms pass through accelerating plates and are caused to curve by a magnet. The heavier atoms curve less, and the lighter ones curve more. When they hit a screen, their mass may be determined. V. Percent Composition A. The percent of the atoms mass over the percent of the molecules mass VI....
View Full Document

This note was uploaded on 04/07/2008 for the course CHEM 184 taught by Professor Hierl during the Fall '07 term at Kansas.

Ask a homework question - tutors are online