Lect_W4_151_WESO (short)

Lect_W4_151_WESO (short) - General Chemistry CHEM 151 Week...

Info iconThis preview shows pages 1–8. Sign up to view the full content.

View Full Document Right Arrow Icon
UA GenChem General Chemistry General Chemistry CHEM 151 CHEM 151 Week 4
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
UA GenChem Week 4 Reading Assignment See D2L
Background image of page 2
UA GenChem Counting Particles Counting Particles Is it practical, in a lab situation, to physically Is it practical, in a lab situation, to physically COUNT COUNT the particles? the particles? NO!! The particles are too small! So – how do we typically measure the amount of a So – how do we typically measure the amount of a substance we have in a laboratory? substance we have in a laboratory? We use the MASS to determine the amount of substance. How is mass related to the number of particles? How is mass related to the number of particles?
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
UA GenChem Relative Mass and Molar Mass 2.0 g of H 2 22.4 L 18.0 g H 2 O 22.4 L 32.0 g O 2 22.4 L 4 Be 9.012 76 Os 190.23 9 F 19.00 Relative Atomic Mass in atomic mass units (amu) Molar Mass if expressed in grams BY EXPERIMENT Each sample contains AVOGADRO’s Number of particles . 76
Background image of page 4
UA GenChem Molar Mass Molar Mass The mass of one mole of atoms is called the Molar The mass of one mole of atoms is called the Molar Mass of the element Mass of the element Average Mass Average Mass (g) (g) = = Molar Mass Molar Mass The Molar Mass is the mass of The Molar Mass is the mass of 6.022 x 10 6.022 x 10 23 23 of of particles of a given substance. particles of a given substance. 1 mol of C 1 mol of C = = 6.0221 x 10 6.0221 x 10 23 23 atoms of C atoms of C M( C ) = 12.0107 g/mol
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
UA GenChem What Makes Them Similar/Different? These are one mole of 6 different substances. If we weigh them, the mass we get is called the “Molar Mass” 6.0221 x 10 23 particles or units in each
Background image of page 6
GenChem NEWS Where is our exam? When? What if you have a class then? When do they stop giving tickets to the other exam? What do you put on the scantron sheet?
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 8
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 03/30/2009 for the course CHEM 151 taught by Professor Staff during the Spring '08 term at University of Arizona- Tucson.

Page1 / 33

Lect_W4_151_WESO (short) - General Chemistry CHEM 151 Week...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online