Chemistry for Engineering Students
4th Edition
ISBN: 9781337398909
Author: Lawrence S. Brown, Tom Holme
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 4, Problem 4.36PAE
4.36 Sometimes students in chemistry labs determine percentage yields greater than 100%. Assuming there is no calculation error, how could this happen?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
The concepts of stoichiometry are similar to those in a cooking recipe. For example, suppose we use the following pizza recipe:
1 crust + 5 ounces tomato sauce + 2 cups cheese --> 1 pizza
The recipe contains the numerical relationship between the pizza ingredients. It says that if we have 2 cups of cheese -- and enough of everything else -- we can make 1 pizza. We can write this relationship as a ratio between the cheese and the pizza.
2 cups cheese : 1 pizza
1) How many pizzas can we make if we have 6 cups of cheese? Assuming that we have enough of everything else. Show work by using the ratio as a conversion factor to calculate the number of pizzas.
2) Suppose that we have 4 crusts, 15 ounces of tomato sauce, and 10 cups of cheese theoretically. How many pizzas can we make?
3) Which one of three ingredients in the above case can give the least amount of pizzas?
4) If this were a chemical reaction, what is the theoretical yield in…
Now we will examine a more complex system. Watch the animation portraying the combustion of propane. The unbalanced chemical equation is
given below.
_C;Hg(g) + _O2(g) → _CO2(g) + _H,O(E)
Begin by balancing an element that appears in the fewest different formulas. What coefficient must be added to the CO2 to balance the element C?
What is the main purpose of this experiment?
Can you explain
Chapter 4 Solutions
Chemistry for Engineering Students
Ch. 4 - Describe the chemical composition of gasoline.Ch. 4 - Write balanced chemical equations for the...Ch. 4 - Prob. 3COCh. 4 - Calculate the amounts of reactants needed in a...Ch. 4 - Prob. 5COCh. 4 - Prob. 6COCh. 4 - Prob. 7COCh. 4 - 4.1 List at least two factors that make it...Ch. 4 - 4.2 What is an alkane?Ch. 4 - 4.3 Explain the difference between complete and...
Ch. 4 - 4.4 Automobile exhaust often contains traces of...Ch. 4 - 4.5 Methane, ethane, and propane are also...Ch. 4 - 4.6 Use the web to research prices of gasoline at...Ch. 4 - For the following reactions, write the ratios that...Ch. 4 - 4.8 In an experiment carried out at very low...Ch. 4 - 4.9 Sulfur, S8, combines with oxygen at elevated...Ch. 4 - 4.10 How many moles of oxygen can be obtained by...Ch. 4 - 4.11 MTBE, C5H12O, is one of the additives that...Ch. 4 - 4.12 In petroleum refining, hydrocarbons are often...Ch. 4 - 4.13 For the following reactions, determine the...Ch. 4 - 4.14 The combustion of liquid chloroethylene,...Ch. 4 - 4.15 What mass of the unknown compound is formed...Ch. 4 - 4.16 Many metals react with halogens to give metal...Ch. 4 - 4.17 Phosgene is a highly toxic gas that has been...Ch. 4 - Prob. 4.18PAECh. 4 - 4.19 How many metric tons of carbon are required...Ch. 4 - 4.20 Assuming a charcoal briquette is composed...Ch. 4 - 4.21 Ammonium nitrate, NH4NO3, will decompose...Ch. 4 - 4.22 Generally, an excess of O2 is needed for the...Ch. 4 - 4.23 In the reaction of arsenic with bromine,...Ch. 4 - 4.24 Ammonia gas can be prepared by the reaction...Ch. 4 - 4.25 When octane is combusted with inadequate...Ch. 4 - 4.26 The equation for one of the reactions in the...Ch. 4 - 4.27 Copper reacts with sulfuric acid according to...Ch. 4 - 4.28 One of the steps in the manufacture of nitric...Ch. 4 - 4.29 When Al(OH)3 reacts with sulfuric acid, the...Ch. 4 - 4.30 Copper reacts with nitric acid via the...Ch. 4 - 4.31 How much HNO3 can be formed in the following...Ch. 4 - 4.32 Hydrogen and oxygen are reacted and the water...Ch. 4 - 4.33 Silicon carbide, an abrasive, is made by the...Ch. 4 - Prob. 4.34PAECh. 4 - Prob. 4.35PAECh. 4 - 4.36 Sometimes students in chemistry labs...Ch. 4 - 4.37 The theoretical yield and the actual yield...Ch. 4 - 4.38 A reaction that produced 4.8 mg of taxol, an...Ch. 4 - Methanol, CH3OH, is used in racing cars because it...Ch. 4 - 4.40 When iron and steam react at high...Ch. 4 - 4.41 The percentage yield of the following...Ch. 4 - 4.42 Sulfur hexafluoride is a very stable gas...Ch. 4 - 4.43 Magnesium nitride forms in a side reaction...Ch. 4 - 4.44 Industrial production of hydrogen gas uses...Ch. 4 - 4.45 If 21 g of H2S is mixed with 38 g of O2 and...Ch. 4 - 4.46 A mixture of 10.0 g of NO and 14.0 g of NO2...Ch. 4 - 4.47 Silicon carbide is, an abrasive used in the...Ch. 4 - 4.48 Elemental phosphorous is used in the...Ch. 4 - 4.49 Small quantities of hydrogen gas can be...Ch. 4 - Prob. 4.50PAECh. 4 - 4.51 What is the role of an indicator in a...Ch. 4 - 4.52 What volume of 0.812 M HCl, in milliliters,...Ch. 4 - Prob. 4.53PAECh. 4 - Prob. 4.54PAECh. 4 - Hydrazine, N2H4, is a weak base and can react with...Ch. 4 - Prob. 4.56PAECh. 4 - Prob. 4.57PAECh. 4 - Prob. 4.58PAECh. 4 - 4.59 Aluminum dissolves in HCI according to the...Ch. 4 - 4.60 Why are fuel additives used?Ch. 4 - 4.61 What is actually measured by the octane...Ch. 4 - Prob. 4.62PAECh. 4 - Prob. 4.63PAECh. 4 - 4.64 Using the web, find information about the...Ch. 4 - 4.65 Using the web, find out how lead “poisons”...Ch. 4 - 4.66 If 3.4 mol Al is mixed with 1.5 times as many...Ch. 4 - 4.67 If 8.4 moles of disilane, Si2H6, are combined...Ch. 4 - 4.68 The pictures below show a molecular-scale...Ch. 4 - 4.69 The pictures below show a molecular-scale...Ch. 4 - 4.70 The particulate scale drawing shown depicts...Ch. 4 - 4.71 The particulate scale drawing shown depict...Ch. 4 - 4.72 The picture shown depicts the species present...Ch. 4 - Prob. 4.73PAECh. 4 - Prob. 4.74PAECh. 4 - Prob. 4.75PAECh. 4 - Prob. 4.76PAECh. 4 - You have 0.954 g of an unknown acid, H2A, which...Ch. 4 - Prob. 4.78PAECh. 4 - 4.79 Phosphoric add (H3PO4) is important in the...Ch. 4 - 4.80 The reaction shown below is used to destroy...Ch. 4 - Prob. 4.81PAECh. 4 - One way of determining blood alcohol levels is by...Ch. 4 - Prob. 4.83PAECh. 4 - 4.84 Aluminum chloride (AlCl3) is used as a...Ch. 4 - 4.85 In the cold vulcanization of rubber, disulfur...Ch. 4 - Prob. 4.86PAECh. 4 - Prob. 4.87PAECh. 4 - 4.88 A quality control technician needs to...Ch. 4 - Prob. 4.89PAECh. 4 - 4.90 Iron metal can be refined (rom the mineral...Ch. 4 - Prob. 4.91PAECh. 4 - Prob. 4.92PAECh. 4 - 4.93 A mixture of methane (CH4) and propane (C3H8)...Ch. 4 - Prob. 4.94PAECh. 4 - Prob. 4.95PAECh. 4 - Prob. 4.96PAECh. 4 - Prob. 4.97PAECh. 4 - Prob. 4.98PAECh. 4 - Prob. 4.99PAECh. 4 - Prob. 4.100PAECh. 4 - Prob. 4.101PAECh. 4 - Prob. 4.102PAECh. 4 - Prob. 4.103PAECh. 4 - 4.104 When 2.750 g of the oxide Pb3O4 is heated to...Ch. 4 - Prob. 4.105PAECh. 4 - 4.106 An ore sample with a mass of 670 kg contains...Ch. 4 - 4.107 Existing stockpiles of the refrigerant...Ch. 4 - 4.108 Elemental analysis is sometimes carried out...Ch. 4 - Prob. 4.109PAECh. 4 - 4.110 Write the balanced chemical equation lot the...Ch. 4 - 4.111 Aluminum metal reacts with sulfuric acid to...Ch. 4 - 4.112 A metallurgical firm wishes to dispose of...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.Similar questions
- 3.83 For the reaction of nitrogen, N2, and hydrogen, H2, to form ammonia, NH3, a student is attempting to draw a particulate diagram, as shown below. Did the student draw a correct representation of the reaction? If not, what was the error the student made?arrow_forwardhat do the coefficients of a balanced chemical equation tell us about the proportions in which atoms and molecules react on an individual (microscopic) basis?arrow_forward3.68 Magnesium is lighter than other structural metals, so it is increasingly important in the design of more efficient vehicles. Mg2+ ions are present in seawater, and the metal is often prepared by "harvesting" these ions and converting them to Mg metal. The average magnesium content of the oceans is about 1270 g Mg2+ per ton of seawater, and the density of seawater is about 1.03 g/mL. What is the molarity of Mg2+ ions in seawater? The design for a concept car calls for 103 kg of magnesium per vehicle. How many gallons of seawater would be required to supply enough magnesium to build one of these ears?arrow_forward
- 3.82 The particulate scale drawing shown depicts the products of a reaction between N2 and O2 molecules. (a) Draw a similar representation for the reactants that must have been present before the reaction took place. (b) Write a balanced chemical equation for the reaction, using the smallest possible whole number coefficients.arrow_forwardConsider an iron bar on a balance as shown. As the iron bar rusts, which of the following is true? Explain your answer. a. The balance will read less than 75.0 g. b. The balance will read 75.0 g. c. The balance will read greater than 75.0 g. d. The balance will read greater than 75.0 g, but if the bar is removed, the rust is scraped off, and the bar replaced, the balance will read 75.0 g.arrow_forward3.107 As computer processor speeds increase, it is necessary for engineers to increase the number of circuit elements packed into a given area. Individual circuit elements are often connected using very small copper “wires” deposited directly onto the surface of the chip. In some processors, these copper interconnects are about 22 nm wide. How many copper atoms would be in a 1-mm length of such an interconnect, assuming a square cross section? (The density of copper is 8.96 g/cm3.)arrow_forward
- Consider the reaction. heat 2 Al(s) + Fe,O,(s) → Al, O, (s) + 2 Fe(1) If 23.1 kg Al reacts with an excess of Fe, O,, how many kilograms of Al, O, will be produced? mass of Al, 0, produced: kgarrow_forwardNaphthalene, a common organic compound, was synthesized during a lab exercise. The theoretical yield was calculated to be 9.3740 g. After the synthesized naphthalene was purified and dried, its mass was taken. The mass of the empty weigh boat used was 0.1055 g and the mass of the weigh boat plus naphthalene was 5.5110 g. What is the percent yield of naphthalene? (Express your answer as a percentage to two decimal places).arrow_forward-1 A geochemist measures the concentration of salt dissolved in Lake Parsons and finds a concentration of 4.27 g·L *. The geochemist also measures the concentration of salt in several nearby non-isolated lakes, and finds an average concentration of 2.6 g-L. Assuming the salt concentration in Lake Parsons before it became isolated was equal to the average salt concentration in nearby non-isolated lakes, calculate the percentage of Lake Parsons which has evaporated since it became isolated. Be sure your answer has the correct number of significant digits.arrow_forward
- 6. Mass calculation in a chemical equation. Make sure to write formula and pathway of how $009560 you solve the problem. Clearly identify what conversions equations you will be using (like I did in the recorded lecture). Your answer (and your molar mass) should have correct number of significant figures and units. SHOW ALL YOUR WORK to receive credit! In the decomposition reaction,50.10 g of calcium chlorate was heated to produce calcium chloride and oxygen gas. What is the mass of oxygen gas produced from this reaction? 3412 Ca(CIO3)2 (S) CaCl2 (s) + 3 O2 (g Atomic Mass Ca= 40.078 ans anoitosen) enot C(= 35.453 n 2 slummet Ils bas empriscio Sus egoisups algol len.bne asigmon of W GM 23 0=15.994 biste atsingologs oms elelgroo The Jinpis Solid 8+ (a) 's(HCarrow_forwardConsider the reaction. heat 2 Al(s) + Fe,0,(s) Al,03(s) + 2 Fe(1) If 11.5 kg Al reacts with an excess of Fe,O2, how many kilograms of Al,0, will be produced? mass of Al,0, produced: kgarrow_forwardI am having a bit of trouble with significant figures and rounding. In a question such as the one below, would the sig fig I put in my answer be correct? How many moles are present in 3.44 g CoCl2 ꞏ 6H2O? = (Which sig fig amount is correct-->) .0217 moles or .021 moles The whole answer was 0.02177904, would I round this answer to the 3rd sig fig? So, is the correct answer actually .022?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Chemistry for Engineering StudentsChemistryISBN:9781337398909Author:Lawrence S. Brown, Tom HolmePublisher:Cengage LearningChemistryChemistryISBN:9781305957404Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCostePublisher:Cengage Learning
- Introductory Chemistry: A FoundationChemistryISBN:9781337399425Author:Steven S. Zumdahl, Donald J. DeCostePublisher:Cengage LearningWorld of Chemistry, 3rd editionChemistryISBN:9781133109655Author:Steven S. Zumdahl, Susan L. Zumdahl, Donald J. DeCostePublisher:Brooks / Cole / Cengage Learning
Chemistry for Engineering Students
Chemistry
ISBN:9781337398909
Author:Lawrence S. Brown, Tom Holme
Publisher:Cengage Learning
Chemistry
Chemistry
ISBN:9781305957404
Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:Cengage Learning
Introductory Chemistry: A Foundation
Chemistry
ISBN:9781337399425
Author:Steven S. Zumdahl, Donald J. DeCoste
Publisher:Cengage Learning
World of Chemistry, 3rd edition
Chemistry
ISBN:9781133109655
Author:Steven S. Zumdahl, Susan L. Zumdahl, Donald J. DeCoste
Publisher:Brooks / Cole / Cengage Learning
Types of Matter: Elements, Compounds and Mixtures; Author: Professor Dave Explains;https://www.youtube.com/watch?v=dggHWvFJ8Xs;License: Standard YouTube License, CC-BY