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Chang - Chemistry 9/e (Homework)

James Finch

Chemistry - College, section 1, Fall 2011

Instructor: Dr. Friendly

Current Score : 1 / 15

Due : Sunday, September 4, 2011 07:30 EDT

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Question
Points
1 2 3 4 5 6
1/4 0/2 0/1 0/6 0/1 0/1
Total
1/15 (6.7%)

  • Description

    Chemistry 9/e by Raymond Chang published by McGraw-Hill Higher Education now has animations with conceptual questions and tutorial problems offering feedback and hints to guide student content mastery, as well as over 1150 end-of-chapter questions. You can check out a sampling of this exciting development below.

    Designed by teachers for teachers, WebAssign is easy to use and reliable -- a trusted companion to your teaching. Sign up for a Free Trial today!

    Click here for a list of all of the questions coded in WebAssign.

    Question 1 is an animation with an assignable quiz attached.

    Question 2 is a follow-up Practice Exercise which checks student understanding of the related Example in the textbook. Practice Exercise 13, for example, is directly related to Exercise 13.

    Question 3 and 4 are algorithmic end-of-chapter problems with conditional feedback added to the numerical answers.

    Question 5 is a supplemental multiple choice questions, with explanatory solutions. These questions provide additional coverage of topics throughout the textbook.

    Question 6 is a testbank question.

Assignment Submission

For this assignment, the number of submissions for each answer box is counted independently. The number of submissions remaining changes only if you submit a new or changed answer.

1. 1/4 points All Submissions Notes Question: Chang9 3.Animation.02.
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0 0/1 1 0/1 0/1
1/50 1/50 1/50 1/50 1/50
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1/4
 
Stoichiometry Use the animation to answer the following questions.
clear dot clear dot clear dot
clear dot clear dot
clear dot
clear dot
clear dot
(a) In the reaction of H2 with O2, if the maximum grams of O2 are used:
     Your answer is incorrect.


(b) In the reaction of H2 with O2, if 6 moles of H2 molecules are used:
     Your answer is incorrect.


(c) When H2 reacts with I2, as the number of moles of product increases:
     Your answer is correct.


(d) In the reaction producing HI, if 768 grams of HI form:
     Your answer is incorrect.


(e) Consider the reaction: H + H H2. This is the only reaction in the animation in which:
     Your answer is incorrect.

Your work in question(s) will also be submitted or saved.
2. 0/2 points All Submissions Notes Question: Chang9 3.PracticeEx.13.
Question part
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1 2
0/1 0/1
1/50 1/50
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0/2
 
about this problemPractice Exercise 3.13
The reaction between nitric oxide (NO) and oxygen to form nitrogen dioxide (NO2) is a key step in photochemical smog formation.
2 NO(g) + O2(g) 2 NO2(g)
(a) How many moles of NO2 are formed by the complete reaction of 0.384 mole of O2?
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.0.768
Your response differs from the correct answer by more than 10%. Double check your calculations. moles

(b) How many grams of NO2 are formed by the complete reaction of 2.24 g of NO?
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.3.43
Your response differs significantly from the correct answer. Rework your solution from the beginning and check each step carefully. grams
HINTS
I'm Stuck

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3. –/1 points Notes Question: Chang9 3.EOCP.073.
Question part
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0/1
 
Each copper(II) sulfate unit is associated with five water molecules in crystalline copper(II) sulfate pentahydrate (CuSO4·5 H2O). When this compound is heated in air above 100°C, it loses the water molecules and also its blue color.

CuSO4·5 H2O CuSO4 + 5 H2O

If 7.60 g of CuSO4 are left after heating 11.88 g of the blue compound, calculate the number of moles of H2O originally present 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.
 moles
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4. –/6 points Notes Question: Chang9 3.EOCP.115.
Question part
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Submissions
1 2 3 4 5 6
0/1 0/1 0/1 0/1 0/1 0/1
0/50 0/50 0/50 0/50 0/50 0/50
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0/6
 
Calculate the number of cations and anions in each of the following compounds.
(a) 8.56 g of KBr
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Enter a number with the correct number of significant figures.
 cations
WebAssign will check your answer for the correct number of significant figures.
Enter a number with the correct number of significant figures.
 anions
(b) 5.50 g of Na2SO4
WebAssign will check your answer for the correct number of significant figures.
Enter a number with the correct number of significant figures.
 cations
WebAssign will check your answer for the correct number of significant figures.
Enter a number with the correct number of significant figures.
 anions
(c) 7.40 g of Ca3(PO4)2
WebAssign will check your answer for the correct number of significant figures.
Enter a number with the correct number of significant figures.
 cations
WebAssign will check your answer for the correct number of significant figures.
Enter a number with the correct number of significant figures.
 anions

Your work in question(s) will also be submitted or saved.
5. 0/1 points All Submissions Notes Question: Chang9 3.Supp.7-09.
Question part
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Submissions
1
0/1
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0/1
 
Which of the following chemical equations is NOT balanced?
     Your answer is incorrect.

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6. 0/1 points All Submissions Notes Question: Chang9 3.TB.006.
Question part
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Submissions
1
0/1
1/50
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0/1
 
The mass of 1.21 multiplied by 1020 atoms of sulfur is
     Your answer is incorrect.

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