Moles and Avogadro’s Numbers:
moles
particles
Name:___________________
Date:__________Period:____
The MOLE is simply a number equal to 602,200,000,000,000,000,000,000 or 6.022 x 1023 (1 mole = 6.022 x
1023 particles) . This number is called AVOGADRO’S NUMBER . How large is a mole?? Well, if you had a mole
of pennies, you would have enough money to pay all the expenses of the United States for the next billion
years. A mole of large marshmallows would cover the United States to a depth of more than 600 miles.
Questions
1. There are three main “representative particles” in chemistry. Match the following with its description –
atoms, formula unit, molecule
_______________ smallest part of a single element
______________ smallest part of a covalent compound
______________ smallest part of an ionic compound
Determine the number of representative particles in each of the following. Show your work!
𝒘𝒘𝐞𝐞 𝐚𝐚𝐚𝐚𝐚𝐚 𝐠𝐠𝐠𝐠𝐠𝐠𝐠𝐠𝐠𝐠 𝐟𝐟𝐟𝐟𝐟𝐟𝐟𝐟 𝐦𝐦𝐦𝐦𝐦𝐦𝐦𝐦 → 𝐚𝐚𝐚𝐚𝐚𝐚𝐚𝐚𝐚𝐚, 𝐬𝐬𝐬𝐬 𝐰𝐰𝐰𝐰 𝐦𝐦𝐦𝐦𝐦𝐦𝐦𝐦𝐦𝐦𝐦𝐦𝐦𝐦𝐦𝐦
2. 0.250 mol silver
0.25 𝑚𝑚𝑚𝑚𝑚𝑚 𝐴𝐴𝐴𝐴 × 6.022 E23 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎/𝑚𝑚𝑚𝑚𝑚𝑚 = 1.50𝑥𝑥1023 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 𝐴𝐴𝐴𝐴
3. 8.56 x 10-3 mol NaCl
4. 35.4 mol CO2
5. 0.425 mol N2
Determine the number of moles in each of the following. Show your work!
𝐰𝐰𝐰𝐰 𝐚𝐚𝐚𝐚𝐚𝐚 𝐠𝐠𝐠𝐠𝐠𝐠𝐠𝐠𝐠𝐠 𝐟𝐟𝐟𝐟𝐟𝐟𝐟𝐟 𝐚𝐚𝐚𝐚𝐚𝐚𝐚𝐚𝐚𝐚 → 𝐦𝐦𝐦𝐦𝐦𝐦𝐦𝐦, 𝐬𝐬𝐬𝐬 𝐰𝐰𝐰𝐰 𝐝𝐝𝐝𝐝𝐝𝐝𝐝𝐝𝐝𝐝𝐝𝐝
6. 3.25 x 1020 atoms Pb
3.25𝐸𝐸20 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 𝑃𝑃𝑃𝑃 ÷ 6.022E23𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎/𝑚𝑚𝑚𝑚𝑚𝑚 = 1 = 0.00054 𝑚𝑚𝑚𝑚𝑚𝑚 𝑃𝑃𝑃𝑃
7. 4.96 x 1024 molecules glucose
8. 1.56 x 1023 formula units NaOH
9. 1.25 x 1025 Cu2+ ions
Make the following conversions. Show your work!
10. 1.51 x 1015 atoms Si to mol Si
11. 4.25 x 10-2 mol NO2 to molecules NO2
12. 8.95 x 1025 molecules CCl4 to mol CCl4
13. 5.90 mol Ca to atoms Ca
HANDOUT