Download Honors Chemistry Unit 4 Student Packet: Honors Chemistry Problem

Honors Chemistry Unit 4 Student Packet:
Honors Chemistry Problem Set Chapter 10:
Classify each of these statements as always true (AT); sometimes true (ST); or never true (NT).
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
Solve
1.
2.
3.
4.
5.
6.
A mole of a pure substance contains 6.02 x 1023 atoms.
The representative particle of a compound is the molecule.
A mole of CCl4 is composed of one atom of carbon and four atoms of chlorine.
A mole of carbon atoms has mass approximately three times as great as the mass of a mole of helium
atoms.
The molar mass of nitrogen is 14.0g.
One mole of any gas occupies a volume of 22.4L.
For a substance of known molar mass, the number of moles of a sample can be calculated from the mass of
the sample.
The volume occupied by one mole of a gas is dependent on the Molar mass of the gas.
The volume of a gas at STP can be calculated from the number of molecules of the gas.
It is necessary to know the formula of a compound in order to calculate its percent composition.
If the percent by mass of carbon in methane, CH4, is 75%, then 100 grams of methane contain 25.0g of
hydrogen.
The formula for methane is both a molecular and an empirical formula.
The empirical formula for glucose, C6H12O6 is C2H4O2.
the following Problems:
How many moles of lead are 9.3 x 1015 atoms of lead?
How many molecules of water are in 5.00g of water?
How many moles of lead (II) oxide are 3.50 x 10 26 formula units of lead (II) oxide?
How many atoms of chlorine are in 102.00g of chlorine gas, Cl 2?
How many moles of carbon tetrafluoride are in 35.67g?
Calculate the molar mass for each of the following:
a. Potassium chloride
c. aluminum carbonate
b. Sodium sulfide
d. iron (III) oxide
7. Convert the following expressed in grams into moles.
a. 25.38 g tin (II) iodide
d. 15.57 g bismuth (III) hydroxide
b. 190.42g magnesium chloride
e. 0.572g of calcium phosphide
c. 50.0 g aluminumfluoride
8. Convert the following moles to grams.
a. 0.25 mol barium nitrate
d. 0.152 mol phosphoric acid
b. 5.00 mol calcium chloride
e. 0.418 mol iron (III) nitrate
c. 2.54 mol potassium chromate
9. Convert the following representative particles into grams.
a. 4.69 x 1022 atoms calcium
c. 2.94 x 1020 molecules of dinitrogen monoxide
b. 5.62 x 1018 formula units of sodium iodide
d. 1.21 x 1026 formula units calcium hydroxide
10. Calculate the percent composition for the following compounds.
a. CH2O
b. Ammonium chloride
c. Ammonium sulfate
11. Analysis of a compound shows that it consists of 43.40 g of copper and 10.95g of sulfur. What is the
percentage composition of this compound?
12. A compound consisting of carbon, hydrogen and oxygen weighs 40.85g. Analysis shows that the compound
contains 10.90g of carbon and 0.90g hydrogen. What is the percentage composition of the compound?
13. Analysis of an ore of calcium shows it to contain 13.61 g of calcium and 21.77g of oxygen in a sample
weighing 46.28 g the rest of the sample is sulfur. What is the percentage composition of this compound?
14. Determine the empirical formula for the compounds in numbers 11 –13
15. What is the molecular formula of a compound that is 25.93% nitrogen and 74.07% oxygen? It has a molar
mass of 216.0g/mol.
16. The percentage composition of ethane gas is 80.0% carbon and 20.0% hydrogen. The molecular weight for
ethane is 30 g/mol. What is the molecular formula for this compound?
17. A gaseous compound is found to have the following composition: 30.5% nitrogen and 69.5% oxygen. The
molecular weight of the gas is found to be 91.8. What is the molecular formula?
18. How many atoms of hydrogen are in 4.56 g of ammonium sulfate
Answers:
1.
1.5 x 10-8
2. 1.67 x 1023
3. 581 mol
4. 1.73 x 1024 atoms
5. 0.405 mol
6. a. 74.55
b. 78.05 c. 233.99 d. 159.70
7. a. 0.06813mol b. 2.000 mol c. 0.595 mol d.
0.05988mol e. 0.00314mol
8. a. 65g b. 555g c. 493g d. 14.9g e. 101g
9. a. 3.12g b. 0.00140g c. 0.0215g d. 14900g
10. a. C-40.0% H-6.7% O-53.3% b. N-26.2% H-7.5% Cl66.35% c. N-21.2% H-6.1% S-24.3% O-48.4%
11. Cu-79.85% S-20.15%
12. C-26.68% H-2.20% O-71.12%
13. Ca-29.41% O-47.04% S-23.50%
14. Cu2S ; CHO2 ; CaSO4
15. N4O10
16. C2H6
17. N2O4
18. 1.66 x 1023
Honors Chemistry: Equation Writing Homework
solid
Replace the words with the appropriate symbols (pages 322,323 in your book)
Forms, produces, yields
liquid
Reaction is heated
gas
Reaction required a catalyst of
MnO2
Aqueous
or
a solution of
precipitate
Replace the words with the appropriate symbols and formulas for each compound.
Ex. When solid iron is mixed with solid sulfur and heated, solid iron (III) sulfide is formed.
Fe(s)
1.
2.
3.
4.
5.
6.
7.
8.
9.
+
S(s) →
Fe2S3 (s)
When solid zinc is added to a solution of copper (II) sulfate, aqueous zinc sulfate and a precipitate of
copper are formed.
When solid magnesium chlorate is heated, solid magnesium chloride and gaseous oxygen is formed.
Solid sulfur reacts with oxygen gas to form gaseous sulfur trioxide.
Solutions of silver nitrate and sodium bromide react to form aqueous sodium nitrate and a precipitate of
silver bromide.
When electricity is applied to liquid water, it decomposes into hydrogen gas and oxygen gas.
Mercury(II) oxide is heated to produce solid mercury and gaseous oxygen.
Aqueous potassium iodide and aqueous lead(II) nitrate react to produce solid lead(II) iodide and a solution
of potassium nitrate.
Solid aluminum reacts with oxygen gas to form solid aluminum oxide.
Aqueous magnesium chloride and aqueous ammonium nitrate react to form aqueous magnesium nitrate and
ammonium chloride gas.
10. In the presence of manganese (IV) oxide, phosphorus and oxygen will react to form phosphorus pentoxide.
Student Reaction Prediction Practice
Synthesis:
1.
2.
3.
4.
5.
calcium and oxygen react to form:
zinc and sulfur react to form:
sodium oxide and water:
zinc and chlorine react:
zinc oxide and water:
Decomposition:
1. silver oxide is heated
2. copper (I) chloride is heated:
3. sodium chlorate is heated:
4. aluminum carbonate is heated:
5. lithium hydroxide decomposes:
Single Replacement:
1. zinc is mixed with lead(II) nitrate
2. aluminum is mixed with nickel (II) sulfate
3. barium is mixed with water (cold water)
4. copper is mixed with iron(II) sulfate
5. aluminum is mixed with iron (II) oxide
Double Replacement:
1. silver nitrate is mixed with sodium chloride
2. iron (III) nitrate is mixed with potassium hydroxide
3. lithium hydroxide is mixed with iron (III) nitrate
4. cobalt (II) acetate is mixed with sodium hydroxide
5. calcium chloride is mixed with sodium sulfide
Combustion:
1. Iron(III) is combusted
2. mercury is combusted
3. CH4 is combusted
4. C5H12 is combusted
5. C3H6 is combusted
Honors Chemistry: Problem Set Chapter 11
Classify each of these statements as always true (AT); sometimes true (ST); or never true (NT)
1. In an equation, a substance is shown to be in the gaseous state by placing an upwardpointing arrow after its formula.
2. The symbol ∆ placed over the arrow in an equation means that heat is supplied to the
reaction.
3. Atoms are destroyed in a chemical reaction.
4. A skeleton equation is not a balanced equation.
5. A non-metal can replace another nonmetal from a compound in a single-replacement
reaction.
6. In a decomposition reaction, there is a single reactant.
7. Spectator ions are not part of a net ionic equation.
8. A precipitate is formed when two ionic solutions are mixed.
9. Classify the following reactions as Synthesis, Decomposition, Single Replacement, Double
Replacement or Combustion. Then balance the equations.
a. Fe + Br2 →
FeBr3
b. C6H14 + O2 →
CO2 + H2O
c. N2 + H2 → NH3
d. Li + H2O → LiOH + H2
e. NaNO3 → NaNO2 + O2
f. C6H14 + O2 → CO2 + H2O
g. NH4Cl →
NH3 + HCl
h. BaO + H2O → Ba(OH)2
i. AgNO3 + NaCl → AgCl + NaNO3
j. Ca(ClO3)2 → CaCl2 + O2
k. Ca3(PO4)2 + Al2(SO4)3 →
CaSO4 + AlPO4
l. FeS + O2 → Fe2O3 + SO2
m. Rb + HC2H3O2 → RbC2H3O2 + H2
10. Write chemical equations from the following word equations.
a. When heated, zinc reacts with hydrogen bromide gas (gaseous hydrobromic acid)
to produce solid zinc bromide and hydrogen gas.
b. Solid iron (II) sulfide reacts with oxygen to form solid iron (III) oxide and sulfur
dioxide gas.
11. Label each of the following as soluble or insoluble.
a. NaNO3
b. PbI2
c. BaCl2
d. FeCl3
e. NaOH
f. Cu(OH)2
g. CaSO4
h. NH4Cl
Do you know the general solubility rules? Recite them to yourself now ;)
12.
On a separate sheet of paper - Predict the products for the following reactants
write balanced equations: If they are double replacement, write a molecular and a net
ionic equation.
a. Lithium plus oxygen
b. Magnesium chlorate decomposes
c. Sodium reacts with water
d. Nitric acid reacts with calcium hydroxide
e. Ethane reacts with oxygen
f. Fluorine reacts with magnesium bromide
g. Copper (II) reacts with silver nitrate
h. Calcium and chlorine react
i. Sodium chlorate decomposes
j. Butane reacts with oxygen
k. copper (II) chloride reacts with sodium sulfide
l. copper reacts with iron (III) sulfate
m. nickel reacts with oxygen
n. sodium iodide reacts with chlorine gas
o. calcium hydride reacts with water
p. magnesium nitrate reacts with potassium hydroxide
q. lithium hydroxide reacts with sodium sulfate
13. List 2 metals that would be able to replace zinc in a single replacement reaction.
14. Which metal will not be able to replace any other metal in a single replacement reaction?
Honors Chemistry: Problem Set Chapter 12
Classify each of these statements as always true (AT); sometimes true (ST); or never true (NT)
1. The coefficients in a balanced chemical equation can be used to form mole ratios relating
reactants to products.
2. To convert molecules to grams you can either use molar mass or Avogadro’s number.
3. One mole of any gas occupies a volume of 22.4L.
4. Mass and the number of moles are conserved in a chemical reaction.
5. Molar mass us used to convert mass to moles.
6. In a volume-volume problem, the 22.4L /mol factors always cancel out.
7. For a mass-mass problem, the first conversion is from moles to mass.
8. Because mole ratios from balanced equations are numbers and not measurements, they do not
enter into the determination of significant figures.
Solve:
1. Balance the following equation and write all of the mole ratios contained in it.
Sb + I2  SbI3
2. Consider the synthesis of aluminum oxide from its elements:
a. If 5.4 moles of aluminum react, how many moles of oxygen are needed?
b. If 88.4 g of aluminum react with excess oxygen, how much aluminum oxide is produced?
c. If 6.3 moles of aluminum oxide is produced, how many liters of oxygen gas were used?
3. Iron reacts with copper (II) nitrate according to the following equation.
a. How many grams of copper can be collected if 44.7 g of iron react with excess copper (II)
nitrate?
b. 1.24 x 1023 atoms of iron react, how much copper II) nitrate is needed?
c. How many moles of copper are produced from 0.65 moles of copper (II) nitrate?
d. When 45.0 mL of 0.25 M copper (II) nitrate react, how much iron would be needed to
complete the reaction?
e. If 80.4 g of iron react, what volume of 0.50 M copper (II) nitrate is needed?
4. Consider the synthesis of ammonia from its elements:
a. How many grams of nitrogen are needed to reacts with 4.25 moles of hydrogen gas?
b. How many grams of ammonia does this produce?
c. How many molecules of hydrogen are needed to react with 0.43 moles of nitrogen?
5. Consider the reaction between potassium phosphate and magnesium chloride:
a. How many mL of 0.10M potassium phosphate are needed to react completely with 62.0mL
of 0.10M magnesium chloride?
b. How much precipitate is formed when 23.4 mL of 0.10 M potassium phosphate react
completely?
6. Consider the decomposition of potassium chlorate.
a. What is the percent yield if 50.0 g of KClO3 are reacted and 17.6 g of oxygen are
collected from the reaction?
7. Consider iron (III) nitrate reacting with ammonium hydroxide:
a. Determine the limiting reagent if 80.0g of iron (III) nitrate react with 135.0 g of
ammonium hydroxide.
b. What is the maximum amount of ammonium nitrate that can be formed from this reaction?
c. What is the percent yield if only 30.0 g of ammonium nitrate is collected at the end of the
reaction?
8. Consider the combustion of magnesium:
a. Determine the limiting reactant if 7.24 moles of magnesium react with 3.86 moles of
oxygen.
b. How much magnesium oxide is formed?
c. What is the percent yield if 288.0 g of magnesium oxide is collected?
9. Consider the synthesis of aluminum iodide:
a. Determine the limiting reactant if 13.5 g of aluminum react with 0.72 moles of iodine.
b. What is the maximum amount of aluminum iodide that could be formed from this reaction?
c. What if the percent yield if only 188 g of aluminum iodide is formed?
10. In a reaction between zinc and hydrochloric acid, what is the theoretical yield for zinc chloride
when 150.0 mL of 6.0M hydrochloric acid react? What is the percent yield for the reaction if
only 50.0g of zinc chloride was collected?
11. 12.5 g of copper are reacted with excess chlorine gas and 25.4 g of product is formed. Calculate
the theoretical and the percent yield.
Answers:
2. a) 4.05 mol O2 b) 167 g Al2O3
c) 210 L O2
3. a) 76.4 g Cu b) 58.0g Cu(NO3)2
c) 0.65 mol Cu
4. a) 39.7 g N2 b) 48.2 g NH3
c) 7.8 x 1023 molec. H2
5. a) 41.3 mL
b) 0.31g
6. 89.8%
7. a) Fe(NO3)3 b) 79.5 g NH4NO3
c) 37.7%
8. a) Mg
b) 292g MgO
c) 98.6%
2
9. a) I2
b) 195.6 g= 2.0 x 10 g AlI3
c) 96.1%
10. 61.3 g, 81.5%
11. 26.5 g CuCl2, 95.80%
d)0.42g
e) 4.3L
Honors Chemistry: Problem Set Special Applications of Reaction Stoichiometry:
1. If 90.0 g of sodium is dropped into 80.0 g of water, how many grams of hydrogen would be
produced?
2. What is the mass of the excess reactant left form the reaction in problem #1?
3. How many grams of calcium hydroxide would be formed if 100. g of calcium were added to 100.mL
of water. (Remember the density of water is 1.00g/mL)
4. If 10.0 g of hydrogen and 40.0 g of oxygen are mixed in a steel reaction vessel and ignited, How
much water vapor is produced?
5. What other gas is found in the reaction vessel from problem #4 when the reaction is complete
and how much is present?
6. Is 50.0 g of chlorine gas enough to replace 30.0 g of bromine form a solution of sodium bromide?
7. Copper (I) sulfide reacts with oxygen to form copper (I) oxide and sulfur dioxide in the first step
of the purification of copper ore. If the copper ore is 90.0 % copper (I) sulfide, how many grams
of the ore would be needed to produce 500. g of copper (I) oxide?
8. Chemists sometimes obtain calcium by reacting calcium oxide with aluminum. If the sample of
calcium oxide is 85.0% pure, what mass of calcium would be produced form 500.g of the calcium
oxide sample?
9. An ore containing 80.0 % zinc sulfide is heated with oxygen gas to produce zinc oxide and sulfur
dioxide in the first step of the purification of zinc. The zinc oxide is then reduced to zinc by the
reaction with carbon. This also produces carbon monoxide. How many grams of zinc oxide would
be obtained from a 250.g sample of the ore?
10. What mass of air that is 23.0% oxygen by mass are required for the reaction of 93.0 g
phosphorus with oxygen to produce diphosphorus pentoxide?
11. How many kilograms of carbon dioxide can be produced from the combustion of 1.00 kg of coke
(an ore of carbon) that is 90.0% carbon?
Extra Credit:
A sample of impure copper having a mass of 1.25 g was dissolved in nitric acid to yield copper (II)
nitrate. If was subsequently converted to copper (II) hydroxide, then to copper (II) oxide, then to
copper (II) chloride and finally to copper (II) phosphate. During each step, there was not loss of
copper. The pure dry copper (II) phosphate had a mass of 2.00 g. Calculate the percent of pure copper
in the impure sample.
Answers:
1. 3.91 g H2
2. 9.54 g H2O
3. 185 g Ca(OH)2
4. 45.0 g H2O
5. 5.00 g H2
6. Yes
7. 617 g ore
8. 304. g Ca
9. 167 g ZnO
10. 522 g air
11. 3.30 kg CO2
Honors Chemistry Review Unit 4
1)
2)
3)
4)
5)
6)
An automobile engine can be powered by the combustion of methane. When the methane ignites, the
products of the reaction expand violently, driving the pistons of the engine and eventually the wheels of
the car.
a) Write the balanced chemical equation for this reaction w/ state symbols.
b) What forms of energy are involved in the process?
Chemical reactions can be classified on the basis of whether they absorb or release energy. Study the
placement of the energy terms in each of the following and state whether the reaction is endothermic or
exothermic. Then write in coefficients to balance each equation.
a) ___C(s) + __O2(g) ___CO(g) + energy
Type_________
b) ___N2O4(g) + energy ___N2(g) +__O2(g)
Type_________
c) ___CaCl2(S) + __O2(g)__CaO(S) + __Cl2(g) + energy
Type_________
d) __SO2(g) + __CO2(g) + energy  __SO3(g) + __CO(g)
Type_________
e) __NH4Cl(s) + energy  __NH4Cl(aq)
Type_________
Write balanced chemical equations for the following word equations.
a)
Oxygen gas plus nitrogen gas to give nitrogen dioxide gas.
b)
Aqueous beryllium iodide plus aqueous tin(II) nitrate to give aqueous beryllium nitrate and solid
tin(II) iodide
c)
Aqueous ammonium sulfate plus aqueous lead(II)chlorate to give aqueous ammonium chlorate and
solid lead(II) sulfate
d)
Aqueous hydrogen carbonate to give liquid water and carbon dioxide gas.
e)
Liquid water plus carbon monoxide gas to give hydrogen gas and carbon dioxide gas.
Classify the following reactions as single replacement, double replacement, synthesis, combustion or
decomposition.
a. 2Na(s) + NiCl2(aq)  2NaCl(aq) + Ni(s)
b. Cu(s) +I2(s)  2CuI(s)
c. 3Sr(OH)2(aq) + 2FeCl3(aq) 3SrCl2(aq) +2Fe(OH)3(s)
d. 2Na2CO3(s) 2Na(s) + O2(g) + 2CO2(g)
e. 2Ca(s) +O2(g) 2CaO(s)
f. 2H2(g) + 2S2(s) + 3O2(g)  2H2SO3(g)
g. C2H5OH + 3O2  2CO2 + 3H2O
For each of the following reactions, predict the products by writing complete and balanced equation. Put
state symbols on the products.
a. zinc reacts with silver nitrate
b. Calcium chloride reacts with sodium phosphate
c. pentane combusts
d. Phosphorus trichloride decomposes
e. Sodium and fluorine react
f. Manganese (II) combusts
g. Barium oxide reacts with water
h. Iron (II) chlorate decomposes
i. Lithium hydroxide decomposes
j. Strontium carbonate decomposes
Will an Iron nail placed in a solution of silver nitrate cause the silver to come out of solution and collect on
the bottom of the beaker? Note: Iron (III) is the most common ion of iron.
a. Write a balanced chemical equation for the reaction.
b. List three other elements that could replace silver.
c. After the reaction described takes place there will be a solution of iron(III) nitrate. Choose a
metal that will precipitate the iron and write a balanced chemical equation.
7)
8)
9)
10)
11)
12)
13)
14)
15)
16)
17)
18)
19)
20)
21)
22)
For each of the following, indicate if the reaction is always spontaneous, never spontaneous or sometimes
spontaneous.
a. N2(g) + H2(g)  NH3(g) + 80 kJ
b. Fe2O3 (s) + C(s) + 10kJ  CO(g) + Fe(s)
c. 2C8H18 + 25O2  16CO2(g) + 18H2O(g) + energy
For each of the following, determine if entropy is decreasing or increasing.
a. I2 (s)  I2(g)
b. Air is cooled and liquefied
c. Water is boiled
d. Ice is melted
e. H2(g) + Br2(l)  2HBr(g)
f. H2(g) + Br2(l)  2HBr(g)
g. Salt dissolves
Classify each of the systems as always spontaneous, never spontaneous, or depends on temperature.
a. entropy decreases, heat is released
b. entropy decreases, heat is absorbed
c. entropy increases, heat is absorbed
d. entropy increases, heat is released
How many moles of hydrogen gas are needed to react with 15.1g chlorine gas as they react?
How many liters of oxygen gas are needed to react completely with 16.2 moles of hydrogen gas as they
react?
How many moles product are formed when 36.5g when calcium reacts completely with oxygen gas?
How many grams of aluminum are required to produce 410g of product through combustion of aluminum?
How many grams of iodine are produced by the decomposition of 24.4g of hydrogen iodide gas?
Chromium(III) reacts with copper(II) sulfate
a. How many moles of copper would be replaced by 49.49g of chromium?
b. How many grams of chromium would be needed to replace the copper in 200 mL of a .75M solution
of copper (II) sulfate?
8.51 moles of hydrogen and 9.25 moles of oxygen in the reaction in the synthesis of water?
a. How much water will be produced?
b. How much of the reactant in excess is left over?
60.4 g of 97.3% pure copper (II) chlorate decomposes.
a. What is the percent yield if 15.0L of gas is collected?
A student places an 8.00g iron nail in 150.0 mL of 1.2M copper(II) sulfate. During the reaction the iron is
oxidized to iron (III) as the copper is replaced.
a. After the reaction, the mixture is filtered. The mass of the filter paper is 0.97g. What should
the mass of the filter paper be after the mixture is filtered and dried?
b. The student masses the filter paper after the reaction is complete and filtered and records the
mass as 11.98. What is the percent yield of the experiment?
Consider: 7.45g Lithium and 4.20g oxygen
a. How much product will be produced?
b. How much of the reactant in excess is left over?
Consider: 118.10g magnesium is added to 1.6L of 2.00M hydrochloric acid (HCl) solution
a. What is the mass of all of the species that will remain when the reaction is over?
Consider the synthesis of calcium chloride: 45.3 g of calcium reacts with 40.0mL of toxic chlorine gas
a. 0.120 g of calcium chloride is recovered from the reaction, what is the percent yield?
Consider the synthesis of ammonia. 27.60g of N2 and 66.1 L of H2 are present as reactants.
a. What is the mass of all species remaining after the reaction?
b. Consider the synthesis of ammonia. 27.60g of N2 and 66.1 L of H2 are present as reactants. Only
29.5g of NH3 are produced. What is the percent yield?