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Ebbing and Gammon - General Chemistry 9/e (Homework)

James Finch

Chemistry - College, section 1, Fall 2010

Instructor: Dr. Friendly

Current Score: 8/21

Due: Thursday, September 9, 2010 07:30 EDT

About this Assignment

Question
Points
1 2 3 4 5 6 7 8 9
2/4 1/4 0/1 1/3 4 0/2 0/1 0/1 0/1
Total
8/21

Description

General Chemistry 9th Edition by Darrell D. Ebbing and Steven D. Gammon includes more than 1390 end-of-chapter problems plus ChemWork assignments and Thinkwell® lecture videos. Questions provide links to Practice It exercises, Watch It videos, relevant textbook pages, and online, live help.

Questions 1-8 are end-of-chapter problems enhanced with links to Read It, Watch It, Practice It, and Chat About It buttons.

Read It - Relevant textbook pages

Watch It - Watch Its include 5 to 7 minute mini-lectures from Thinkwell®.

Practice It - Practice Its include Visual Exercises that combine molecular-level animations and videos demonstrations that cover core chemistry concepts. Each animation or video is accompanied by questions to aid students in conceptualization of the topic.

Chat About It - Online, live help

Question 9 is a ChemWork assignment. ChemWork assignments test students' understanding of core concepts from each chapter. If a student can solve a particular problem with no assistance, he/she can proceed directly to the answer and receive congratulations. However, if a student needs help, assistance is available through a series of hints. The procedure for assisting the student is modeled after the way an instructor would help a student with a homework problem in his or her office. The hints are usually in the form of interactive questions that guide the student through the problem solving process. Students cannot receive the right answer from the system, rather it encourages them to continue working on the problem through this system of multiple hints. ChemWork is chemically and numerically parametrized so that each student in the course receives a unique set of problems.


Instructions

This demo assignment allows many submissions and allows you to try another version of the same question for practice.



1. 2/4 points All Submissions Notes Question: EbGam9 1.PP.061.
Question part
Points
Submissions
1 2 3 4
0/1 1 1 0/1
2/50 2/50 1/50 7/50
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2/4
 
Do the indicated arithmetic and give the answer to the correct number of significant figures.
(a) (8.79 text( x ) 0.0310)/0.030
WebAssign will check your answer for the correct number of significant figures.
Enter a number with the correct number of significant figures.
Your answer is incorrect.

(b) 0.72 + 91.6
WebAssign will check your answer for the correct number of significant figures.
Enter a number with the correct number of significant figures.
Your answer is correct.

(c) 932 multiplied by 0.00449 + 129
WebAssign will check your answer for the correct number of significant figures.
Enter a number with the correct number of significant figures.
Your answer is correct.

(d) (847.86 - 847.68) multiplied by 14658
WebAssign will check your answer for the correct number of significant figures.
Enter a number with the correct number of significant figures.
Your answer is incorrect.

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2. 1/4 points All Submissions Notes Question: EbGam9 2.PP.084.
Question part
Points
Submissions
1 2 3 4
0/1 0/1 1 0/1
4/50 4/50 1/50 2/50
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1/4
 
Give systematic names to the following binary compounds.
(a) N2F2
Answer is not case sensitive.
Your answer is incorrect.

(b) As4O6
Answer is not case sensitive.
Your answer is incorrect.

(c) ClO2
Answer is not case sensitive.
Your answer is correct.

(d) N2O4
Answer is not case sensitive.
Your answer is incorrect.

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3. 0/1 points All Submissions Notes Question: EbGam9 3.PP.088.
Question part
Points
Submissions
1
0/1
2/50
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0/1
 
Using the following reaction (depicted using molecular models), large quantities of ammonia are burned in the presence of a platinum catalyst to give nitric oxide, as the first step in the preparation of nitric acid.
Suppose a vessel contains 5.4 g of NH3, how many grams of O2 are needed for a complete reaction?
WebAssign will check your answer for the correct number of significant figures.
Enter a number with the correct number of significant figures.
Your answer is incorrect. g

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4. 1/3 points All Submissions Notes Question: EbGam9 3.PP.093.
Question part
Points
Submissions
1 2 3
0/1 1 0/1
0/50 1/50 0/50
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1/3
 
Methanol, CH3OH, is prepared industrially from the gas-phase catalytic balanced reaction that has been depicted here using molecular models.
In a laboratory test, a reaction vessel was filled with 31.7 g CO and 10.7 g H2.
(a) How many grams of methanol would be produced in a complete reaction?
WebAssign will check your answer for the correct number of significant figures.
Enter a number with the correct number of significant figures.
 g

(b) Which reactant remains unconsumed at the end of the reaction?
    

Your answer is correct.



(c) How many grams of it remain?
WebAssign will check your answer for the correct number of significant figures.
Enter a number with the correct number of significant figures.
 g

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5. 4/4 points All Submissions Notes Question: EbGam9 4.PP.056.
Question part
Points
Submissions
1 2 3 4
1 1 1 1
11/50 4/50 1/50 2/50
Total
4/4
 
Obtain the oxidation number for the element noted in each of the following. (Type your answer using the format 2 or -1.)
(a) Cl in HClO4
Answer is not case sensitive.
Your answer is correct.

(b) Cr in CrO3
Answer is not case sensitive.
Your answer is correct.

(c) O in CaO
Answer is not case sensitive.
Your answer is correct.

(d) Hg in Hg2Cl2
Answer is not case sensitive.
Your answer is correct.

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6. –/2 points Notes Question: EbGam9 4.PP.083.
Question part
Points
Submissions
1 2
0/1 0/1
0/50 0/50
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0/2
 
A chemist added an excess of sodium sulfate to a solution of a soluble barium compound to precipitate all of the barium ion as barium sulfate, BaSO4. How many grams of barium ion are in a 513-mg sample of the barium compound if a solution of the sample gave 539 mg BaSO4 precipitate?
WebAssign will check your answer for the correct number of significant figures.
Enter a number with the correct number of significant figures.
 g
What is the mass percentage of barium in the compound?
WebAssign will check your answer for the correct number of significant figures.
Enter a number with the correct number of significant figures.
%

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7. –/1 points Notes Question: EbGam9 5.PP.037.
Question part
Points
Submissions
1
0/1
0/50
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0/1
 
A gas in a closed-tube manometer (shown below) has a measured pressure of 0.057 atm. Calculate the pressure in mmHg.
WebAssign will check your answer for the correct number of significant figures.
Enter a number with the correct number of significant figures.
 mmHg

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8. –/1 points Notes Question: EbGam9 5.PP.087.
Question part
Points
Submissions
1
0/1
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0/1
 
Formic acid, HCHO2, is a convenient source of small quantities of carbon monoxide. When warmed with sulfuric acid, formic acid decomposes to give CO gas.

HCHO2(l) → H2O(l) + CO(g)

If 3.27 L of carbon monoxide was collected over water at 25.0°C and 633 mmHg, how many grams of formic acid were consumed?
WebAssign will check your answer for the correct number of significant figures.
Enter a number with the correct number of significant figures.
 g

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9. –/1 points Notes Question: EbGam9 3.CW.24.
Question part
Points
Submissions
1
0/1
0/50
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0/1
 


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