1 / 9

The MOLE

The MOLE. It’s a beauty mark… It’s a small furry garden pest… No, wait… its how we count ATOMS!. What is a mole?. For counting matter (quantity) in chemistry we use the mole This number means a value ( like a dozen = 12) 1 mole = 6.02 x 10 23 representative particles

maik
Download Presentation

The MOLE

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The MOLE It’s a beauty mark… It’s a small furry garden pest… No, wait… its how we count ATOMS!

  2. What is a mole? • For counting matter (quantity) in chemistry we use the mole • This number means a value (like a dozen = 12) • 1 mole = 6.02 x 1023 representative particles • This value is called Avogadro’s Number

  3. Moles are used to count REPRESENTATIVE PARTICLES • ie. the smallest particle that retains chemical and physical properties • 3 types: • Atoms: Single element • Molecules: covalent compound • Formula Units: Ionic Compounds or ions

  4. Molar Mass • The mass of one mole of a substance • Calculate by adding the atomic masses of all atoms in compound • Molar mass of Fe = • Molar mass of O2= • Molar mass of Cu(OH)2=

  5. Percent Composition • The percent BY MASS of each element in a compound • Ex: K2Cr2O7

  6. Empirical Formula • The lowest whole number ratio of atoms of the element in a compound • Ex: C6H12O6 CH2O

  7. Molecular Formula • The actual number of atoms in a chemical compound (not reduced) • Can be derived from empirical formula and molar mass of molecular formula • Calculate empirical mass and divide molar mass by the empirical mass. • Example: Empirical Formula= CH2; Molar mass= 28g Molecular formula: C76H52O46

  8. Empirical Formula from Percent Composition • Example: A compound was found to be 54.53% Carbon, 9.15% Hydrogen, and 36.32% Oxygen. Find its Empirical Formula. • Assume a 100g sample (change %  g) • Use molar mass to find moles of each • Divide all moles by the smallest number of moles • The resulting whole numbers are the coefficients of the empirical formula

More Related