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Catalyst. Wait for your test to get passed back. Then… 1. Write down one objective that you did well on 2. Write down the objective that you did the worst on 3. Correct at least one of your wrong answers (write the correct answer on your packet, not the test). Today’s Agenda.
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Catalyst Wait for your test to get passed back. Then… • 1. Write down one objective that you did well on • 2. Write down the objective that you did the worst on • 3. Correct at least one of your wrong answers (write the correct answer on your packet,not the test)
But first! • Unit 6: Stoichiometry
What is a dozen? If I have 2 dozen bagels, how many is that?
Mole Not this kind of mole… A mole is = 6.02 x 1023 of something Kind of like the way we use ‘dozen’ but way bigger.
Molar Mass We use “dozen” as the measurement for eggs, and we use “moles” as the measurement for atoms. Molar mass = Amount that 1 mole of something weighs. If a dozen eggs weigh 1 lb., how much would 2 dozen eggs weigh?
A little bit of review The subscript (small number) applies to the element directly before it and tells you how many of each element you have. If there is no number, how many do we assume there are? Ex. H2O
Molar Mass • The “molar mass” of something is the mass of one mole of that thing. It is measured in g/mol • Remember, the mass of each element is listed on the periodic table. • We’ve called this “atomic mass”, we’ve called this “average atomic mass”, but now we’re calling it the “molar mass”. These are all the same thing. • What is the molar mass for Fe? • Cl? • H?
Compounds • The molar mass of a compound is calculated by multiplying the subscript by the mass of the element and adding the totals. • What is the molar mass of H2O? • CO2? • CH4?
GUIDED PRACTICE! – 1o minutes • I will display a compound on the board. • You will then have 60 seconds to determine its molar mass. • I will tell you when to show your boards • Whiteboards! • Expectations: • Use the whiteboards only for Chemistry! • Hold up your answer no matter what • No talking in between questions so that I can explain the answer
GUIDED PRACTICE! NO2
GUIDED PRACTICE! FeCl3
GUIDED PRACTICE! UF6
GUIDED PRACTICE! H2Te
INDEPENDENT PRACTICE! • Reminders: • You should be working independently • You should be working quietly • If you need help, please ask by raising your hand! • Raise your hand for help and I will come over to you as soon as I can
Independent Practice 1. CaH2 7. Li3P 2. Ca(OH) 8. BF3 3. CH4 9. As2(NO3) 4. MgO 10. Ca(CO3) 5. CCl4 6. H2SO4
Exit Slip 1. How many atoms are in the compound H2(CO3)? 2. What is the molar mass of Nickel? 3. What is the molar mass of H2(CO3)? 4. What is the molar mass of NaCl?