7.E: Exercises
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When solid iron is exposed to air and moisture, it begins to change color in the process of rusting. Rust (\(\ce{Fe2O3}\)) is the product that forms when solid iron reacts with gaseous oxygen. Write a balanced equation to show the formation of solid rust when solid iron reacts with gaseous oxygen. The following unbalanced equation represents the formation of nitric oxide. Answer the question that follows this equation:
\[ \ce{Fe} (s) + \ce{O2} (g) \rightarrow \ce{Fe2O3} (s)\nonumber\]
What are the coefficients that correctly balance this equation? List the coefficients in order they should appear in the above equation, separating them with commas.
Nitric oxide (\(\ce{NO}\)) is an important gas in health in that it relaxes the inner muscles of blood vessels to minimize high blood pressure. The following unbalanced equation represents the formation of nitric oxide. Answer the question that follows for this equation.
\[ \ce{N2} (g) + \ce{O2} (g) \rightarrow \ce{NO} (g)\nonumber\]
What are the coefficients that correctly balance this equation? List the coefficients in order they should appear in the above equation, separating them with commas.
Use the molecular image to classify each of the following as a chemical change or physical change:
a. 
b. 
c. 
d. 
In which of the following is a chemical change occurring?
a. Boiling water in a pan
b. Cutting a piece of thread
c. Melting ice in a pitcher of tea
d. Burning paper
Why are burning candles and rusting nails examples of chemical changes? Select the multiple reasons below which apply.
a. The composition stays the same
b. The composition changes
c. There are some color changes
d. The temperature also changes
e. The temperature stays same
Acetaminophen the active ingredient in Tylenol\(\circledR\) is synthesized using the reaction below:
\[\ce{C6H7NO} + \ce{C4H6O3} \rightarrow \ce{C8H9NO2} + \ce{C2H4O2}\nonumber\]
Which set of numbers represents the correct coefficients for the balanced equation?
a. 1,1,1,1
b. 1,2,2,3
c. 2,2,2,2
d. 3,4,3,2
Antacids (Tums, Maalox, Mylanta) are ingested to relieve heartburn through neutralization reactions of the bases with gastric juice (\(\ce{HCl}\)). Which set of numbers represents the correct coefficients for the neutralization equation when balanced?
\[\ce{HCl} (aq) + \ce{CaCO3} (s) \rightarrow \ce{H2O} (l) + \ce{CaCl2} (aq) + \ce{CO2} (g) \nonumber\]
a. 2, 1, 1, 1, 1
b. 1, 2, 2, 1, 1
c. 2, 2, 2, 1, 3
d. 1, 2, 3, 2, 1
Identify the product of the following double replacement reaction:
\[\ce{CuCl2} (aq) + \ce{K2S} (aq) \rightarrow \nonumber\]
a. \(\ce{CuK2}\) & \(\ce{SCl2}\)
b. \(\ce{CuS}\) & \(\ce{KCl}\)
c. \(\ce{CuCl}\) & \(\ce{KS}\)
d. \(\ce{KCu}\) & \(\ce{ClS2}\)
Write the balanced chemical equation for the reaction depicted by molecular models. (Note: carbon: gray, hydrogen: white and oxygen: red)
a. \(\ce{C2H6O} \rightarrow \ce{C2H4} + \ce{H2O}\)
b. \(\ce{C2H6O} \rightarrow \ce{C2H4} + \ce{H2O2}\)
c. \(2\ce{C2H6O} \rightarrow \ce{C2H4} + 2\ce{H2O}\)
d. \(4\ce{C2H6O} \rightarrow \ce{C2H4} + 2\ce{H2O}\)
Balance the following equation.
\[\ce{Cr} (s) + \ce{S8} (aq) \rightarrow \ce{Cr2S3} (s) \nonumber\]
Which set of numbers represents the correct coefficients for the balanced equation?
a. 1, 1, 1
b. 8, 2, 8
c. 8, 3, 8
d. 16, 2, 8
e. None of the choices are correct
During aerobic cellular respiration, glucose molecules (\(\ce{C6H12O6}\)) are combined with the oxygen we breathe. Carbon dioxide and water are released. Write a balanced chemical reaction for this process.
Types of Chemical Reactions
When magnesium ribbon burns in air, magnesium oxide is produced as show in the equation that follows. What is the classification of this reaction?
\[2\ce{Mg} (s) + \ce{O2} (g) \rightarrow 2\ce{MgO} (s)\nonumber\]
a. single replacement
b. double replacement
c. decomposition
d. combination
When copper wire burns in air, copper(II) oxide is produced as shown in the equation that follows. What is the classification of this reaction?
\[2\ce{Cu} (s) + \ce{O2} (g) \rightarrow 2\ce{CuO} (s) \nonumber\]
a. single replacement
b. double replacement
c. decomposition
d. combination
Below is the reaction of hydrogen peroxide (\(\ce{H2O2}\)), which is catalyzed by the enzyme catalase in biological systems. What is the classification of this reaction?
\[2\ce{H2O2} (aq) \rightarrow 2\ce{H2O} (l) + \ce{O2} (g)\nonumber\]
a. single replacement
b. double replacement
c. decomposition
d. combination
When zinc is added to a blue solution of copper(II) sulfate, the blue color begins fading. What is the classification of this reaction?
\[\ce{Zn} (s) + \ce{CuSO4} (aq) \rightarrow \ce{ZnSO4} (aq) + \ce{Cu} (s)\nonumber\]
a. single replacement
b. double replacement
c. decomposition
d. combination
Hydrochloric acid can be neutralized by treating it with sodium hydroxide according to the equation below. What is the classification of this reaction?
\[\ce{HCl} (aq) + \ce{NaOH} (aq) \rightarrow \ce{NaCl} (aq) + \ce{H2O} (l) \nonumber\]
a. single replacement
b. double replacement
c. decomposition
d. combination
Classify the reaction below:
a. Single replacement
b. Combination
c. Decomposition
d. Double replacement
Identify the type of reaction that is occurring:
\[\ce{Fe2S3} (s) \rightarrow 2\ce{Fe} (s) + 3\ce{S} (s) \nonumber\]
a. Double replacement
b. Single replacement
c. Combination
d. Decomposition
e. Double combination
Matching: Classify each of the following as a combination, decomposition, single replacement, double replacement, or combustion reaction.
| Reaction | Classification |
|---|---|
| \(\ce{H2} (g) + \ce{Br2} (g) \rightarrow 2\ce{HBr} (g)\) | |
| \(\ce{AgNO3} (aq) + \ce{NaCl} (aq) \rightarrow \ce{AgCl} (s) + \ce{NaNO3} (aq)\) | |
| \(2\ce{H2O2} (aq) \rightarrow 2\ce{H2O} (l) + \ce{O2} (g)\) | |
| \(\ce{CuO} (s) + 2\ce{HCl} (aq) \rightarrow \ce{CuCl2} (aq) + \ce{H2O} (l)\) | |
| \(\ce{Zn} (s) + \ce{CuCl2} (aq) \rightarrow \ce{Cu} (s) + \ce{ZnCl2} (aq)\) | |
| \(\ce{C5H8} (g) + 7\ce{O2} (g) \rightarrow 5\ce{CO2} (g) + 4\ce{H2O} (g)\) |
Matching: Identify each reaction as combination, decomposition, combustion, single replacement, or double replacement.
a. \(3\ce{Sr} (s) + \ce{N2} (g) \rightarrow \ce{Sr3N2} (s)\)
b. \(\ce{CH4} (g) + 2 \ce{O2} (g) \rightarrow \ce{CO2} (g) + 2 \ce{H2O} (g) +\) energy
c. \(2\ce{Ag} (s) + \ce{H2S} (aq) \rightarrow \ce{Ag2S} (s) + \ce{H2} (g)\)
d. \(\ce{AgNO3} (aq) + \ce{NaCl} (aq) \rightarrow \ce{AgCl} (s) + \ce{NaNO3} (aq)\)
e. \(\ce{CaCO3} (s) \rightarrow \ce{CaO} (s) + \ce{CO2} (g)\)
Oxidation-Reduction Reactions
The following are important reactions that occur in the cells. Identify each as an oxidation or reduction reaction.
a. \(\ce{Fe^{3+}} (aq) + e^- \rightarrow \ce{Fe^{2+}} (aq) \)
b. \(\ce{Fe^{2+}} (aq) \rightarrow \ce{Fe^{3+}} + e^- \)
c. \(\ce{C4H6O4} \rightarrow \ce{C4H4O4} + 2\ce{H} \)
d. \(\ce{C18H32O2} + 2\ce{H2} \rightarrow \ce{C18H36O2} \)
Identify the oxidized and reduced species in the following reaction:
\[\ce{Ca} (s) + \ce{Br2} (g) \rightarrow \ce{CaBr2} (s) \nonumber\]
a. \(\ce{CaBr2}\) is reduced and \(\ce{Br2}\) is oxidized.
b. \(\ce{Ca}\) is reduced and \(\ce{Br2}\) is oxidized.
c. \(\ce{Ca}\) is oxidized and \(\ce{Br2}\) is reduced.
d. \(\ce{CaBr2}\) is reduced and \(\ce{Ca}\) is oxidized.
e. \(\ce{CaBr2}\) is oxidized, and \(\ce{Ca}\) is reduced.
The Lithium-Iodine battery is used in pacemakers to generate small electrical impulses that trigger the heart to beat according to the following equation. Identify the species oxidized.
\[2\ce{Li} (s) + \ce{I2} (s) \rightarrow 2\ce{LiI} (aq)\nonumber\]
a. \(\ce{Li}\)
b. \(\ce{I2}\)
c. \(\ce{LiI}\)
d. None of these
In the following reactions, identify the reactant that is oxidized, and the reactant that is reduced.
\[2\ce{Li} (s) + \ce{F2} (g) \rightarrow 2\ce{LiF} (s) \nonumber\]
\[\ce{Cl2} (g) + 2\ce{KI} (aq) \rightarrow 2\ce{KCl} (aq) + \ce{I2} (s) \nonumber\]
a. \(\ce{Li}\) is reduced, \(\ce{F}\) is oxidized.
\(\ce{Cl}\) is reduced, \(\ce{I}\) is oxidized
b. \(\ce{Li}\) is oxidized, \(\ce{F}\) is reduced.
\(\ce{Cl}\) is reduced, \(\ce{I}\) is oxidized.
c. \(\ce{Li}\) is oxidized, \(\ce{F}\) is reduced.
\(\ce{Cl}\) is oxidized, \(\ce{I}\) is reduced.
d. \(\ce{Li}\) is reduced, \(\ce{F}\) is oxidized.
\(\ce{Cl}\) is oxidized, \(\ce{I}\) is reduced.
e. \(\ce{Li}\) is oxidized, \(\ce{F}\) is reduced.
\(\ce{K}\) is reduced, \(\ce{I}\) is oxidized.
The Mole
Note that Avogadro’s number is \(6.02 \times 10^{23}\).
a. How many atoms are present in one mole of an element?
b. How many atoms are present in 1.50 moles of \(\ce{Na}\)?
c. How many atoms are present in 0.750 moles of \(\ce{Al}\)?
d. How many moles are present in \(1.51 \times 10^{24}\) atoms of \(\ce{Ca}\)?
e. How many moles are present in \(3.01 \times 10^{24}\) molecules of \(\ce{O2}\)?
We all know that an elephant has a trunk and four legs and therefore a dozen elephants will have 12 trunks and 48 legs. Now put on your chemistry hats and tell me how many trunks and legs are there in 1 mole of elephants?
a. \(6.022 \times 10^{23}\) trunks and \(6.022 \times 10^{23}\) legs
b. \(6.022 \times 10^{23}\) trunks and \(2.408 \times 10^{23}\) legs
c. \(6.022 \times 10^{23}\) trunks and \(2.408 \times 10^{24}\) legs
d. \(6.022 \times 10^{27}\) trunks and \(6.022 \times 10^{23}\) legs
How many atoms of \(\ce{O}\) are in 0.350 mole of glucose, \(\ce{C6H12O6}\)?
a. 2.1 atoms \(\ce{O}\)
b. \(3.49 \times 10^{-24}\) atoms \(\ce{O}\)
c. \(1.26 \times 10^{24}\) atoms \(\ce{O}\)
d. \(2.10 \times 10^{23}\) atoms \(\ce{O}\)
e. \(5.81 \times 10^{-25}\) atoms \(\ce{O}\)
Calculate the number of \(\ce{Li}\) atoms in 4.5 moles of \(\ce{Li}\).
a. \(7.5 \times 10^{24}\) atoms
b. \(7.5 \times 10^{-24}\) atoms
c. \(2.8 \times 10^{24}\) atoms
d. \(2.7 \times 10^{24}\) atoms
e. \(2.7 \times 10^{-24}\) atoms
Conversion factors can be generated based on a balanced chemical reaction. For the reaction below, identify which conversion factor is not valid:
\[\ce{C} (s) + \ce{O2} (g) \rightarrow \ce{CO2} (g) \nonumber\]
a. 1 mole \(\ce{C}\) = 1 mole \(\ce{O2}\)
b. 2 moles \(\ce{O2}\) = 1 mole \(\ce{CO2}\)
c. 1 mole \(\ce{CO2}\) = 1 mole \(\ce{O2}\)
d. 1 mole \(\ce{CO2}\) = 1 mole \(\ce{C}\)
Conversion factors can be generated based on a balanced chemical reaction. For the reaction below, identify which conversion factor is not valid:
\[4\ce{Fe} (s) + 3\ce{O2} (g) \rightarrow 2\ce{Fe2O3} (s) \nonumber\]
a. 4 moles \(\ce{Fe}\) = 3 moles \(\ce{O2}\)
b. 3 moles \(\ce{O2}\) = 2 moles \(\ce{Fe2O3}\)
c. 2 moles \(\ce{Fe2O3}\) = 6 moles \(\ce{O2}\)
d. 4 moles \(\ce{Fe}\) = 2 moles \(\ce{Fe2O3}\)
The world population is estimated to be 7.8 billion. If the population would remain constant, how long would it take for one mole of rice grains to be fully consumed? Assume that everyone eats one bowl of rice containing 3,000 grains, three times a day.
a. 42 days
b. 379 years
c. 24 million years
d. 10 billion years
Molar Mass
Choose the option that best describes molar mass:
a. The mass of one atom of a pure substance
b. The sum of protons and neutrons of an atom
c. The mass of the most abundant isotope of an element
d. The mass of one mole of a substance
Use the periodic table below to answer the next set of questions relating to molar mass.
Baking soda also known as sodium bicarbonate (or sodium hydrogen carbonate) is a common household chemical. Determine the molar mass (rounding, with no decimals) of baking soda, \(\ce{NaHCO3}\). (Note: Only enter the numerical value with no additional characters or units, or your answer will be marked incorrect.)
Calculate the molar mass (rounding, with no decimals) of \(\ce{Ca3(PO4)2}\). (Note: Only enter the numerical value with no additional characters or units, or your answer will be marked incorrect.)
Ethylene oxide (\(\ce{C2H4O}\)) is used by hospital workers to sterilize medical equipment and supplies. Determine the molar mass (rounding, with no decimals) of ethylene oxide, \(\ce{C2H4O}\). (Note: Only enter the numerical value with no additional characters or units, or your answer will be marked incorrect.)
Sulfanilamide is a sulfur compound with antibacterial properties with the structure shown below (\(\ce{C}\): gray, \(\ce{H}\): White, \(\ce{N}\): blue, \(\ce{S}\): yellow and \(\ce{O}\): red):
Determine the molecular formula and molar mass of sulfanilamide:
a. \(\ce{C6H8N2O2S}\) and 172.2 g/mol
b. \(\ce{C6H8N2O2S}\) and 182.2 g/mol
c. \(\ce{C7H8N2O2S}\) and 172.2 g/mol
d. \(\ce{C6H8N2O2S2}\) and 172.2 g/mol
Calculate the molar mass of propofol (\(\ce{C12H18O}\)), a medication used to sedate patients under critical care.
a. 151.16 g/mol
b. 178.26 g/mol
c. 133.34 g/mol
d. 161.34 g/mol
Naloxone (\(\ce{C19H21NO4}\)) is a drug that can treat opioid overdose in a hospital setting. Calculate the molar mass (rounding, with no decimals) of this drug. (Note: only enter the numerical value with no additional characters or units, or your answer will be marked incorrect).
Remdesivir (\(\ce{C27H35N6O8P}\)) is an antiviral drug that aids in combatting a variety of RNA viruses. Calculate the molar mass (rounding, with no decimals) of this drug. (Note: only enter the numerical value with no additional characters or units, or your answer will be marked incorrect).
Using the values provided, calculate the molar mass (rounding, with no decimals) for the following compound. (Note: only enter the numerical value with no additional characters or units, or your answer will be marked incorrect).
Calculations Using Molar Mass
Aspirin, \(\ce{C9H8O4}\), is commonly used to treat pain, fever, and inflammation. Given that the formula weight of aspirin is 180. g/mol, calculate the moles of aspirin in 208 mg sample?
a. \(6.02 \times 10^{23}\) moles
b. 21.0 moles
c. 1.16 moles
d. \(1.16 \times 10^{-3}\) moles
Phenacetin, \(\ce{C9H8O4}\), is one of the compounds used in Tylenol to treat pain, and fever. Given that the formula weight of phenacetin is 179 g/mol, calculate the moles of phenacetin in 416 mg sample?
a. \(6.02 \times 10^{23}\) moles
b. 21.0 moles
c. \(1.16 \times 10^{-3}\) moles
d. \(2.32 \times 10^{-3}\) moles
Acetaminophen, \(\ce{C8H9NO2}\), present in Tylenol is commonly used to treat pain and fever. Given that the formula weight of acetaminophen is 151 g/mol, calculate the moles of acetaminophen in 208 mg sample?
a. \(6.02 \times 10^{23}\) moles
b. \(1.38 \times 10^{-3}\) moles
c. \(1.16 \times 10^{-3}\) moles
d. \(2.32 \times 10^{-3}\) moles
Aspirin, \(\ce{C9H8O4}\), is commonly used to treat pain, fever, and inflammation. Given that the formula weight of aspirin is 180. g/mol, calculate the moles of aspirin in 418 mg sample?
a. \(6.02 \times 10^{23}\) moles
b. \(1.38 \times 10^{-3}\) moles
c. \(1.16 \times 10^{-3}\) moles
d. \(2.32 \times 10^{-3}\) moles
Phenacetin, \(\ce{C9H8O4}\), is one of the compounds used in Tylenol to treat pain, and fever. Given that the formula weight of phenacetin is 179 g/mol, calculate the moles of phenacetin in 376 mg sample?
a. \(6.02 \times 10^{23}\) moles
b. \(2.10 \times 10^{-3}\) moles
c. \(1.16 \times 10^{-3}\) moles
d. \(2.32 \times 10^{-3}\) moles
A bottle of the pain reliever ibuprofen (\(\ce{C13H18O2}\), molar mass 206.3 g/mol) containing 600 tablets. 200-mg coated tablets as shown below:
How many moles of ibuprofen does the bottle contain?
a. 0.582 moles
b. 2.91 moles
c. 0.969 moles
d. 0.000969 moles
A patient took 1.3 grams of aspirin (\(\ce{C9H8O4}\)) for a really bad headache. How many moles of aspirin did she take? Report your answer to two significant figures in standard notation.
Mole Relationships in Chemical Equations
(Arithmetic) Answer the following questions using the balanced chemical equation:
\[\ce{N2} (g) + 3\ce{H2} (g) \rightarrow 2\ce{NH3} (g) \nonumber\]
How many moles of \(\ce{H2}\) are needed to react with 2.75 moles \(\ce{N2}\)?
(Arithmetic) Answer the following questions using the balanced chemical equation:
\[\ce{N2} (g) + 3\ce{H2} (g) \rightarrow 2\ce{NH3} (g) \nonumber\]
How many moles of \(\ce{NH3}\) are produced from 2.75 moles of \(\ce{N2}\)?
(Arithmetic) Answer the following questions using the balanced chemical equation:
\[\ce{N2} (g) + 3\ce{H2} (g) \rightarrow 2\ce{NH3} (g) \nonumber\]
How many moles of \(\ce{H2}\) are used up if 0.680 moles of \(\ce{NH3}\) are produced?
(Arithmetic Question) Caffeine is a bitter stimulant drug found in varying quantities in seeds and plant leaves. Its formula is \(\ce{C8H10N4O2}\). Calculate the number of moles of nitrogen in \(\{x\}\) moles of caffeine.
Naproxen is used to treat pain and inflammation caused by arthritis. Naproxen has formula of \(\ce{C14H14O3}\). How many moles of carbon (\(\ce{C}\)) are present in 2.30 moles of naproxen?
a. 32.2 moles of \(\ce{C}\)
b. 14.0 moles of \(\ce{C}\)
c. 6.09 moles of \(\ce{C}\)
d. 0.16 moles of \(\ce{C}\)
Mass Calculations for Chemical Reactions
In the following equation, how many grams of \(\ce{O2}\) are needed to react with 24.0 g of \(\ce{NH3}\)?
\[4\ce{NH3} (g) + 3\ce{O2} (g) \rightarrow 2\ce{N2} (g) + 6\ce{H2O} (l) \nonumber\]
a. 45.1
b. 33.9
c. 45.0
d. 135.5
e. 22.6
Which of the following represents a “molecular” formula for dinitrogen tetroxide?
a. \(\ce{N2O4}\)
b. \(\ce{NO2}\)
c. \(\ce{N4O2}\)
d. \(\ce{N2O}\)
What is the mass percent of nitrogen in acetaminophen, \(\ce{C8H9NO2}\)?
Find the number of atoms in 2.0 moles of molecular oxygen (\(\ce{O2}\)). Show two significant figures in your answer.
What is the mass (in kilograms, kg) that corresponds to \(6.02 \times 10^{23}\) atoms of sodium (\(\ce{Na}\))? Show two significant figures in your answer.
Limiting Reactants and Percent Yield
The recipe used to make the delicious nursing chemistry supreme pizza is
\[\text{1 crust + 5 ounces tomato sauce + 2 cups cheese} \rightarrow \text{1 pizza}\nonumber\]
Suppose we have 8 crust, 20 cups of cheese and 30 ounces of tomato sauce, what is limiting reagent (LR) and the theoretical yield of pizzas you can make.
a. 8 pizzas, crust LR
b. 20 pizzas, cheese LR
c. 6 pizzas, tomato sauce LR
d. 3 pizzas tomato sauce LR
e. 4 pizzas, crust LR
(Matching) Consider the given mixture that contains \(X\) and \(Y\) molecules, represented by the blue and red spheres, respectively. Given each of the following reactions, identify the reactant that is limiting the given reaction:
a. \(X + Y \rightarrow Z\)
b. \(2X + Y \rightarrow Z\)
c. \(X + 2 Y \rightarrow Z\)
d. \(3X + 2Y \rightarrow 2Z\)
Iron (III) oxide reacts with carbon monoxide to produce iron and carbon dioxide (hint: the molar mass of \(\ce{Fe2O3}\) is 160 g/mol, and \(\ce{Fe}\) is 56 g/mol).
\[ \ce{Fe2O3} (s) + 3\ce{CO} (g) \rightarrow 2\ce{Fe} (s) + 3\ce{CO2} (g) \nonumber\]
What is the percent yield of iron if the reaction of 65.0 g of iron (III) oxide produces 15.0 g of iron?
a. 67
b. 3
c. 33
d. 100
e. 50
(Arithmetic) 2.784 g of copper sulfate reacted with excess zinc metal. 0.702 g copper metal was obtained according to the equation:
\[\ce{CuSO4} (aq) + \ce{Zn} (s) \rightarrow \ce{Cu} (s) + \ce{ZnSO4} (aq) \nonumber\]
What is the percent yield?
Magnesium oxide can be made by heating magnesium metal in the presence of oxygen gas, according to the following equation:
\[2 \ce{Mg} (s) + \ce{O2} (g) \rightarrow 2\ce{MgO} (s) \nonumber\]
When 10.1 g of magnesium reacts with 10.5 g of oxygen, 11.9 g of magnesium oxide is formed. Determine the limiting reagent, theoretical yield and percent yield for the reaction.
Energy Changes in Chemical Reactions
How much heat in kJ is required in the reaction below to form 50.0 g of carbon dioxide? Use 44.0 g/mol as the molar mass for \(\ce{CO2}\). Write your answer, with no decimals.
\[\ce{CO} (g) + \ce{SiO2} (s) \rightarrow \ce{SiO} (g) + \ce{CO2} (g) \nonumber\]
\(\Delta H\) = +520.9 kJ
(Multi-select) Select the following that are TRUE statements for an endothermic reaction.
a. Heat is absorbed.
b. Heat is released.
c. The energy of the products is greater than the energy of the reactants.
d. The energy of the products is less than the energy of the reactants.
e. Heat is a product.
f. Heat is a reactant.
\[\ce{N2} (g) + 3\ce{H2} (g) \rightarrow 2\ce{NH3} (g) \nonumber\]
\(\Delta H\) = −92.2 kJ
Identify an incorrect interpretation of the above reaction:
a. When one mole of nitrogen gas reacts with three moles of hydrogen gas, two moles of ammonia gas are produced, and 92.2 kJ of heat is produced.
b. This reaction is exothermic.
c. Conversion factor for \(\ce{N2}\) and heat is -92.2 kJ/1 mole \(\ce{N2}\)
d. Conversion factor for \(\ce{H2}\) and heat is -92.2 kJ/3 mole \(\ce{H2}\)
e. Conversion factor for \(\ce{NH3}\) and heat is -92.2 kJ/1 mole \(\ce{NH3}\)
Use the energy diagram below to answer the following questions:
a. Which number represents the energy of reactants?
b. Which number represents the enthalpy (energy) of reaction?
c. Does the above energy diagram show endothermic or exothermic? (Enter the entire selected term.)
Use the energy diagram below to answer the following questions:
a. Which number represents the energy of products?
b. Which number represents activation energy?
c. During the above reaction, is energy absorbed or released? (Enter the entire selected term.)