Chemistry 1 Notes # 3b Chapter 11 Section 1 THE MOLE & particle/mass calculations Last updated November 18, 2018

MOLE Moles- SI unit for the amount of a substance.

Practice with Dimensional Analysis Convert 43,000 cm to miles 2.54 cm = 1 in. 12 in. = 1 ft. 3 ft. = 1 yd. 1,760 yds.= 1 mile Convert 3.25 miles to meters

Measuring Matter What is a mole? The Mole is an SI base unit for the amount of a substance. 6.02 x 1023 = number of representative particles in exactly 12 g of Carbon-12 = 1 mole

Whereas a dozen is known as 12 of something, a pair is always 2, and a gross is always 144. This number never changes but what is counted does. The same can be said about the mole

The mole represents 6.02x1023 of something. This number is called Avogadro’s number In chemistry the mole is used to measure how many atoms, particles or molecules something contains

Converting Moles to Particles and Particles to moles Using the mole and knowing how many particles, atoms or molecules, converting from the mole to how many particles and back is simple Problem: How many atoms are in 1.76 mol of Zn

Solution:

Particles to Moles How many mol are in 2.33x1027 particles of Carbon? Actual answer 3870 mol C or 3.87 x 103 mol C

11.2 Mass and the Mole Molar mass  the mass in grams of one mole of any substance. For example: The atomic mass of carbon is 12.01 amu (atomic mass units) therefore the molar mass of carbong is 12.01 grams What is the molar mass of Potassium?

Molar mass of a Compound To determine the molar mass of a compound simply add up the molar mass of each of the individual atoms that make up the compound. Examples: NaCl = 22.99 g + 35.45 g = 58.44g/mol H2O 2(1.01g) + 16.00g= 18.02 g/mol

Using Molar Mass Given moles convert to mass

Using Molar Mass Given Mass convert to moles

Mole Map