Download Honors Unit 3 - Stoichiometry

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Honors Unit 3 Stoichiometry
Homework & Handouts
Miss Adams
Chemistry 1
Name: ______________________________
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Molar Mass Worksheet
Calculate the molar masses of the following chemicals:
1) KOH
2) BeCl2
3) BF3
4) Mg(OH)2
5) UF6
6) H3PO4
7) (NH4)2SO4
8) CH3COOH
9) Pb(NO3)2
10) Ga2(SO3)3
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Mole Conversions Worksheet
Directions: Solve the problems below. Report your answers to the correct number of
significant figures and with the correct units.
***Remember: 1 mole = 6.02 x 1023 representative particles = molar mass (grams)
1. Calculate the number of CO2 molecules in 3.00 moles.
2. Calculate the mass in grams of 5.0 moles of Li.
3. Calculate the number of formula units found in 148.0 g of Ca(OH)2.
4. How many atoms of carbon are in a pencil if the mass of carbon is 2.00 g?
5. How many formula units of MgCl2 would have a mass of 345 kg?
6. Calculate the number of ammonium ions in 0.376 moles of ammonium sulfate.
7. How many potassium atoms are in 0.320 moles of potassium phosphate?
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Empirical & Molecular Formula Problems (pg. 4 & 5)
Show work to solve each problem below. Read each question carefully and think about what you
need to do to solve the problem.
1. A sample of benzotrifluoride was found to contain 57.54 grams of carbon, 3.4 grams of
hydrogen, and 39.10 grams of fluorine after combustion analysis. Determine the empirical
formula of the compound.
2. The molar mass of a compound is 92 g/mol. Analysis of a sample of the compound indicates
that it contains 0.606 g N and 1.390 g O. Find its empirical and molecular formula.
3. Determine the molecular formula of the compound with an empirical formula of CH and a
molar mass of 78.110 g/mol.
-54. What’s the empirical and molecular formula of a molecule containing 18.7% lithium, 16.3%
carbon, and 65.0% oxygen? The molar mass of the compound is 73.8 g/mol.
Name of compound:___________________________________________
5. If 4.04 g of N combine with 11.46 g O to produce a compound with a molar mass of 108.0
g/mol, what is the empirical & molecular formula of this compound?
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Writing Chemical Equations (pg. 6 & 7)
Use the naming & writing rules from Unit 2 as well as the notation we discussed in this unit to write the following chemical equations.
Pay attention to whether a substance is ionic or molecular/covalent when writing the formula!
1. Zinc metal and aqueous lead (II) nitrate react to form aqueous zinc nitrate and solid lead.
2. Aqueous aluminum bromide and chlorine gas react to produce aqueous aluminum chloride and liquid bromine.
3. Aqueous sodium phosphate and aqueous calcium chloride form aqueous sodium chloride and calcium phosphate as a precipitate.
4. Potassium metal and chlorine gas combine to form aqueous potassium chloride.
-75. Aluminum metal and aq. hydrochloric acid (hydrogen chloride) react to form aqueous aluminum chloride and hydrogen gas.
6. Aqueous calcium hydroxide and phosphoric acid (hydrogen phosphate) form calcium phosphate as a precipitate and liquid water.
7. Copper metal and sulfuric acid (hydrogen sulfate) yield aqueous copper (II) sulfate, liquid water, and gaseous sulfur dioxide.
8. Hydrogen gas and nitrogen monoxide gas produce gaseous water and nitrogen gas.
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Balancing Chemical Equations
Place the correct coefficients on the lines to balance the equations below:
1)
____ N2 + ____ H2  ____ NH3
2)
____ KClO3  ____ KCl + ____ O2
3)
____ NaCl + ____ F2  ____ NaF + ____ Cl2
4)
____ H2 + ____ O2  ____ H2O
5)
____ Pb(OH)2 + ____ HCl  ____ H2O + ____ PbCl2
6)
____ AlBr3 + ____ K2SO4  ____ KBr + ____ Al2(SO4)3
7)
____ CH4 + ____ O2  ____ CO2 + ____ H2O
8)
____ C3H8 + ____ O2  ____ CO2 + ____ H2O
9)
____ C8H18 + ____ O2  ____ CO2 + ____ H2O
10)
____ FeCl3 + ____ NaOH  ____ Fe(OH)3 + ____NaCl
11)
____ P + ____O2  ____P2O5
12)
____ Na + ____ H2O  ____ NaOH + ____H2
13)
____ Ag2O  ____ Ag + ____O2
14)
____ S8 + ____O2  ____ SO3
15)
____ CO2 + ____ H2O  ____ C6H12O6 + ____O2
16)
____ K + ____ MgBr  ____ KBr + ____ Mg
17)
____ HCl + ____ CaCO3  ____ CaCl2 + ____H2O + ____ CO2
18)
____ HNO3 + ____ NaHCO3  ____ NaNO3 + ____ H2O + ____ CO2
19)
____ H2O + ____ O2  ____ H2O2
20)
____ NaBr + ____ CaF2  ____ NaF + ____ CaBr2
21)
____ H2SO4 + ____ NaNO2  ____ HNO2 + ____ Na2SO4
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-9Balancing Chemical Equations Worksheet
Directions: Place the correct coefficients on the lines in order to balance
the following equations.
1)
____ Na3PO4 + ____ KOH  ____ NaOH + ____ K3PO4
2)
____ MgF2 + ____ Li2CO3  ____ MgCO3 + ____ LiF
3)
____ P4 + ____ O2  ____ P2O3
4)
____ RbNO3 + ____ BeF2  ____ Be(NO3)2 + ____ RbF
5)
____ AgNO3 + ____ Cu  ____ Cu(NO3)2 + ____ Ag
6)
____ CF4 + ____ Br2  ____ CBr4 + ____ F2
7)
____ HCN + ____ CuSO4  ____ H2SO4 + ____ Cu(CN)2
8)
____ GaF3 + ____ Cs  ____ CsF + ____ Ga
9)
____ BaS + ____ PtF2  ____ BaF2 + ____ PtS
10)
____ N2 + ____ H2  ____ NH3
11)
____ NaF + ____ Br2  ____ NaBr + ____ F2
12)
____ Pb(OH)2 + ____ HCl  ____ H2O + ____ PbCl2
13)
____ AlBr3 + ____ K2SO4  ____ KBr + ____ Al2(SO4)3
14)
____ CH4 + ____ O2  ____ CO2 + ____ H2O
15)
____ Na3PO4 + ____ CaCl2  ____ NaCl + ____ Ca3(PO4)2
16)
____ K + ____ Cl2  ____ KCl
17)
____ Al + ____ HCl  ____ H2 + ____ AlCl3
18)
____ N2 + ____ F2  ____ NF3
19)
____ SO2 + ____ Li2Se  ____ SSe2 + ____ Li2O
20)
____ NH3 + ____ H2SO4  ____ (NH4)2SO4
- 10 Balancing Chemical Equations Worksheet
Directions: Place the correct coefficients in front of the formulas in order to
balance the following equations.
1. _____ CaO + _____ P2O5  _____ Ca3(PO4)2
2. _____ Ca3(PO4)2 + _____ H2SO4  _____ CaSO4 + _____ H3PO4
3. _____ NaHCO3 + _____ H2SO4  _____ Na2SO4 + _____ H2O + _____ CO2
4. _____ H2S + _____ Cl2  _____ S8 + _____ HCl
5. _____ Fe(OH)3  _____ Fe2O3 + _____ H2O
6. _____ H3BO3  _____ H4B6O11 + _____ H2O
7. _____ C8H16 + _____ O2  _____ CO2 + _____ H2O
8. _____ Na4P2O7 + _____ Al2(SO4)3  _____ Al4(P2O7)3 + Na2SO4
9. _____ K2CO3 + _____ H3PO4  _____ K3PO4 + _____ H2O + _____ CO2
10. _____ Al4C3 + _____ H2O  _____ CH4 + _____ Al(OH)3
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Writing Word Equations
Directions: Write a balanced symbolic equation from the following word equations
and classify the type of reaction.
1. iron + sulfur  iron (II) sulfide
Type:____________________
2. magnesium chloride + silver nitrate  magnesium nitrate + silver chloride
Type:____________________
3. Calcium oxide + water  calcium hydroxide
Type:___________________
4. Magnesium bromide + chlorine  magnesium chloride + bromine
Type:____________________
5. butane (C4H10) + oxygen  carbon dioxide + water
Type:__________________
6. copper (II) nitrate  copper (II) oxide + nitrogen dioxide + oxygen
Type:____________________
7. potassium chloride + lead (II) nitrate  lead(II) chloride + potassium nitrate
Type:____________________
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Predicting Products
Directions: Predict the product(s) for each reaction. Next, write a balanced
symbolic equation.
1. magnesium + oxygen 
2. sodium chromate + silver nitrate 
3. hydrogen peroxide 
4. Magnesium + iron (III) bromide 
5. heptene (C7H14) + oxygen 
6. copper (II) sulfate + barium hydroxide 
7. sodium iodide + lead (II) nitrate 
8. zinc + copper (II) sulfate 
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Limiting Reactants (pg. 14 & 15)
Show ALL of your work for credit on this assignment!
1. _____ CaO(s) + _____ H2O(l)  _____ Ca(OH)2(aq)
How many grams of calcium hydroxide will be formed in this reaction when 4.44 g of
calcium oxide and 7.77 g of water are available to react? Also identify the limiting reactant.
2. Magnesium undergoes a single replacement reaction with hydrochloric acid.
Balanced Equation:
How many grams of hydrogen gas will be produced from the reaction of 3.00 g of
magnesium with 4.00 g of hydrochloric acid?
Identify the limiting reactant.
- 15 3. Sulfur reacts with oxygen to produce sulfur trioxide gas.
Balanced Equation:
If 6.3 g of sulfur reacts with 10.0 g of oxygen, what is the limiting reactant? How many
grams of sulfur trioxide will be produced?
If 7.01g is actually produced what is the percent yield?