1 Chemistry Chapter 10: The Mole Section 1: Measuring Matter I

Chemistry Chapter 10: The Mole
Section 1: Measuring Matter
I.
Counting particles
a. One ______________ - means _____; eggs, pencils, flowers, etc
b. A new ___________________ unit needed in ___________________ because atoms are very
__________________
c. ______________ - SI base unit used to measure the _______________ of __________________
i. 1 ______________ contains __________________________ particles (atoms, molecules,
formula units, electrons, ions, etc)
d. Avogadro’s number = _________________________________
II.
Converting between _____________________ and __________________________
a. _______________________ factor – used to switch unit systems because the _________ are
_________________________ to each other
b. Conversion factor:
i. 1 mol / ___________________ particles
ii. ______________________ particles/ 1 mol
c. How many molecules are in 3.5 mole of sucrose?
d. How many Zn atoms are in 2.5 mol of Zn?
e. How many moles are in 2.5 x 1024 molecules of sucrose?
f.
How many moles are in 6.92 x 1024 molecules of water?
Section 2: Mass and the Mole
I.
Mass of a ____________
a. Mass of one __________ of each ________________ is _______________________
b. Based on ______________ of the ______________________ atom
c. Molar mass – the __________________ in grams of one ____________ of any
____________________________
i. Numerically __________________ to ________________________
ii. Label: ____________________
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d. Ex: molar mass of Fe = 55.845 g/mol; 1 mole of Fe has a mass of 55.845 g
II.
Molar mass conversions
a. Start with ______________ you _____________
b. Use ___________________________ to cancel out units
c. What is the mass of 3 mol of Copper?
d. What is the mass of 3.57 mol of Aluminum?
e. How many mol are in 120 g of Si?
III.
Practice Problems – Mass & Atoms
a. ____ step problems
i. __________________ to moles to _________________
ii. Atoms to _______________ to mass
b. Use ___________________________ to cancel ________________
i. Molar ______________
ii. Avogadro’s ___________________________
c. How many atoms are in 31.1 g of Au?
d. What is the mass in grams of 5.5 x 1023 atoms of helium gas?
Section 3: Moles of Compounds
I.
Chemical formulas and the mole
a. _________________ formula tells __________________ and _______________ of atoms
i. Represents a ________________ of the compound
b. Can find mole ___________________ factors from a __________________
i. Ex: 1 mol C atoms / 1 mole CCl2F2
c. _________________ relationships from _________________ formulas
i. How many moles of (Al +3) ions are in 1.25 mol of Al2O3?
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II.
Molar mass of compounds
a. To find ___________________ of a _______________________
i. Find ____________________ of each element
ii. _________________ times any __________________
iii. _____________ together
iv. Find the molar mass of CaCl2
v. Find the molar mass of KC2H3O2
vi. Find the molar mass of Sr(NO3)2
III.
Converting compounds
a. Mole to ___________
i. Calculate __________________________ of entire compound
ii. Use ________________________ as a __________________ factor
b. What is the mass of 3.25 mol of H2SO4?
c. What is the mass of 4.35 x 10-2 mol of zinc chloride (ZnCl2)?
d. Determine the number of moles in 22.6 g of AgNO3.
e. How many aluminum ions are present in a sample of 35.6 g of AlCl3?
i. Calculate the molar mass
ii. Convert mass into moles
iii. Convert moles to formula units
iv. Calculate number of ions by using ratio from chemical formula
f.
How many chloride ions are present?
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g. What is the mass in grams of one formula unit of AlCl3?
h. Ethanol (C2H5OH), a domestically produced fuel source, is often blended with gasoline. A sample of
ethanol has a mass of 45.6 g.
i. How many carbon atoms does the sample contain?
ii. How many hydrogen atoms are present?
iii. How many oxygen atoms are present?
Section 4: Empirical and Molecular Formulas
I.
Percent Composition
a. __________________ by mass of each _______________ in a _____________________
b. Analytical _______________ analyze compounds to _____________________ elements they contain
and the __________________ by mass
c. Percent by _________________ (element) = ____________ of element / mass of ___________ x 100
d. Percents by ______________ must add up to ___________
e. Have a 100 g sample of Element X (55g) and Element Y (45g): 55% Element X, 45% Element Y
II.
Percent _____________________ from Chemical Formulas
a. When given only the __________________________, assume you have ______________ of the
substance
b. Determine _______________ of each ________________
c. Calculate _______________________ of the ____________________
d. Percent by ____________ = mass of _____________ in 1 mol of compound/ _______________ of
compound x 100
e. Practice problems p 344
III.
Empirical formula
a. __________________ with the ____________________ whole-number mole ________________ of the
_____________________
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b. Can be _________________ from _____________________
c. Percent to ______________; ________________ to mole: ________________ by small;
________________ ‘til whole
d. If given __________________ composition , assume total ____________ of compound is
_______________
e. Practice Problem: Find the empirical formula of a sample containing 40.05% sulfur and 59.95% oxygen
f.
IV.
P 346
Molecular formula
a. Specifies _______________ number of __________________ of each element in one
__________________ or __________________________ of a substance
b. May or ___________________ be same as _______________________________
c. Must have _________________________ molar mass of ____________________ and
___________________ represented by ____________________________________
d. Experimental _____________________ divided by ________________ of
_____________________________ = ‘n’
e. ___________________________ the subscripts of _______________________________ by ‘n’ to find
__________________________________
f.
Practice Problem: Find the molecular formula for a sample of acetylene with a molar mass of 26.04
g/mol. The empirical formula is CH.
g. P 350
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Section 5: Formulas of Hydrates
I.
Hydrate
a. Compound that has a specific _______________________ of ____________________ molecules bound
to its ___________________
b. Number of ____________________ molecules associated with a ________________________ of a
compound is written ______________________ a ____________
i. Ex:
c. Named with __________________ followed by the word _______________________
d. Prefixes p 351
II.
Analyzing a hydrate
a. ____________________________ - compound without ________________________
b. Heat a _________________________ to drive off water and create ______________________
compound
III.
Uses of ______________________
a. Anyhdrous compounds may be _________________ to materials to help keep them
__________________
b. Used to store ________________________________ , sodium sulfate decahydrate
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