1.2NH THE MOLE & Scientific Notation The mole is defined as a collection of 6.022 × 1023 particles. The atomic mass given on a periodic table that is given in grams is the mass of one mole (6.022 × 1023 particles) of that element. Atomic Number – the 6 number of protons in nucleus EXAMPLE: C Atomic Symbol Molar Mass for Carbon 12.011 As you can see from the example above, one mole of Carbon would have a mass of 12.011 grams. Another way to say this is that 12.011 grams of carbon contains 6.022 × 1023 particles. Avogadro’s number is the basis for the mole. 1 mole is Avogadro’s number of atoms. AVOGADRO’S NUMBER = 6.022 × 1023 particles Examples of Mole Conversions EXAMPLE 1: Determine the number of grams in 3 moles of Carbon? 3_ moles 12.011_ grams MOLES GRAMS 36.033 grams of C 1 mole EXAMPLE 2: How many moles are in 6 grams of Carbon? 6 _ grams _ of _ C mole GRAMS MOLES .5 moles 1 12.011_ grams EXAMPLE 3: How many atoms are in .5 moles? .5 _ moles 6.0221023 atoms MOLES ATOMS = 3.011 x 1023 atoms 1 1_ mole EXAMPLE 4: How many moles is 3.011 x 1023 atoms? 3.0111023 atoms 1_ mole ATOMS MOLES = .5 moles 1 6.0221023 atom EXAMPLE 5: How many atoms is 6 grams of Carbon? 6 _ grams 1_ mole 6.0221023 atoms GRAMS ATOMS 3.01 x 1023 atoms 1 12.011_ grams 1_ mole EXAMPLE 6: How many grams is 3.011 x 1023 atoms of Carbon? 3.0111023 atoms 1_ mole 12.011 _ grams ATOMS GRAMS 6 grams 1 6.0221023 atoms 1_ mole LET’S BE SURE YOUR DOING SCIENTIFIC NOTATION CORRECTLY ON YOUR CALCULATOR. Most students do not use the calculator correctly for Scientific Notation. The E or EE on your calculator creates the x 10 portion of scientific notation. Try entering the following number: 2.3785 X 108 On your calculator Type 2.3785 To get the exponent press 2nd then EE (above the 7) Then enter the exponent 8 The value should appear like this: 2.3785E8 Here are a Couple of Examples for You to Try. A Multiplication Example: -5 8 4.805 X 10 X 2.3785 X 10 = ? Your calculator should read 11428.6925 or 1.14286925 X 104 A Division Example: The mole or Avogadro’s # will look like this in your Calculator if Entered correctly You’ll be using this frequently and often. ( I think that might be a Yogi Bear quote) LAST NAME_______________ FIRST NAME______________ DATE________ PERIOD ____ 1.2 Mole Conversions. PRACTICE EXAMPLES- To complete the practice examples (1) write the type of question you have, (2) write the equation with units, (3) show the cancellation of units and (4) calculate the solution. 1. Determine how many atoms are present in 2.5 moles of Silicon? (15.05 × 1023 atoms) 2. How many moles of Silicon is 3.01 × 1023 atoms? (.5 moles) 3. What is the mass of 4 moles of Iron? (224 grams) 4. How many atoms are in 48.6 grams of Magnesium? (12.04 × 1023 atoms) 5. How many grams are in 18 .06 x 1023atoms of Copper? (190.5 grams) 6. How many moles of Nickel is 176 grams? (3 moles) LAST NAME_______________ FIRST NAME______________ DATE________ PERIOD ____ 1.3 Some Additional Practice with Mole Conversion Questions To complete the practice examples (1) write the type of question you have, (2) write the equation with units, (3) show the cancellation of units and (4) calculate the solution. 1. How many moles are there in 50.2 grams of Oxygen? (3.14 moles) 2. How many atoms are in 2.1 moles of Cobalt?(12.65 ×1023 atoms) 3. How many grams are in 12.04 x 1023 atoms of Lithium? (13.882 grams) 4. What is the mass of three moles of Fluorine? (56.994 grams) 5. What is the mass of 6.02 x 1023 atoms of Sulphur?( 32.066 grams) 6. If you have 55.3 grams of Bromine, how many moles do you have?(.7 moles) 23 7. How many atoms are in 2.68 moles of Aluminum?( 16.14 ×10 atoms) 23 8. How many atoms in 505 grams of Gold? (15.44 ×10 atoms) 9. If you need 24.08 x 1023 Lead atoms, what mass is required?( 828.52 grams) 10. How many moles of Zinc have a mass of 80.1 grams?( 1.22 moles) LAST NAME_______________ FIRST NAME______________ DATE________ PERIOD ____ 1.4 Even More Practice with Mole Conversion Questions To complete the practice examples (1) write the type of question you have, (2) write the equation with units, (3) show the cancellation of units and (4) calculate the solution. 1. How many moles of Calcium are in a mass of 65 grams of Calcium? (1.62 moles) 2. If you need 15.66 x 1023 atoms of Silver, what mass is required? (280.5 grams) 3. What is the mass of 2.5 moles of Copper? (157.5 grams) 4. How many atoms are in 4.3 moles of Potassium? (25.9 x 1023 atoms) 5. How many grams are in 3.011 x 1023 atoms of Gold? (98.5 grams) 6. How many moles are there in 600 grams of Lead? (2.9 moles) 7. How many atoms are there in 600 grams of Lead? (17.4 x 1023 atoms) 8. What is the mass of 2 moles of Zinc? (130.78 grams) .