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Chang - Chemistry 12/e (Homework)

James Finch

Chemistry - College, section 1, Fall 2019

Instructor: Dr. Friendly

Current Score : 11 / 13

Due : Wednesday, September 4, 2019 07:00 EDT

Last Saved : n/a Saving...  ()

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Question
Points
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–/5 –/1 –/1 –/4 –/1 –/1
Total
11/13 (84.6%)

  • Instructions

    WebAssign supports Chemistry, 12th edition, by Raymond Chang, with online questions directly from the textbook, providing you with an easy way to create homework or assessments that perfectly match the approach and style of this title. The text includes animations with conceptual questions and tutorial problems offering feedback and hints to guide student content mastery. More than 1150 end-of-chapter questions are available in WebAssign.

    Question 1 is an animation with an assignable quiz attached.

    Question 2 is a follow-up Practice Exercise that checks student understanding of the related Example in the textbook. Practice Exercise 3.12, for example, is directly related to Exercise 3.12. This question uses WebAssign's chemPad answer entry tool, which provides students with immediate intelligent feedback based on their incorrect answers.

    Questions 3 and 4 are algorithmic end-of-chapter problems with conditional feedback added to the numerical answers. Question 4 asks students to draw Lewis Structures using the Marvin JS application, providing instant assessment of students' molecular drawings.

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

    Question 6 is a test bank question. This demo assignment allows many submissions and allows you to try another version of the same question for practice wherever the problem has randomized values.

    The answer key and solutions will display after the first submission for demonstration purposes. Instructors can configure these to display after the due date or after a specified number of submissions.

Assignment Submission

For this assignment, you submit answers by question parts. The number of submissions remaining for each question part only changes if you submit or change the answer.

Assignment Scoring

Your last submission is used for your score.

1. –/5 points Chang12 9.A.001. My Notes
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Ionic, Nonpolar and Polar Covalent Bonds Use the animation to answer the following questions.
(a) The element that is common to all three examples exhibits which of the following characteristics?
    

(b) In each of the three examples presented, which of the following is true?
    

This animation will begin with a narration when you click "Open in New Window" below. To restart the narration, click "Open in New Window" again.
(c) The first and third examples differ from the second in that:
    

(d) A nonpolar covalent bond is shown as:
    

(e) Consider the following representation given for the bond formed in the third example.

Which of the following could be correctly stated about this diagram?
    
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2. –/1 points Chang12 3.PE.012. My Notes
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about this problemPractice Exercise 3.12
Balance the equation representing the reaction between chromium(III) oxide, Cr2O3, and carbon monoxide (CO) to yield chromium (Cr) and carbon dioxide (CO2). (Use the lowest possible whole number coefficients. Omit states-of-matter from your answer.)

chemPad

Help

 
Cr2O3 + 3 CO  →  2 Cr + 3 CO2
HINTS
I'm Stuck
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3. –/1 points Chang12 3.EOCP.073. My Notes
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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 8.50 g of CuSO4 are left after heating 13.30 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.(No Response) seenKey

0.266

 moles
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4. –/4 points Chang12 9.EOCP.045. My Notes
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Draw the correct Lewis structures for the following molecules. (Draw all atoms. Assign lone pairs, radical electrons, and atomic charges where appropriate.)
(a) P4 (each P is bonded to three other P atoms)
(No Response)
Marvin JS


(b) COBr2 (C is bonded to O and Br atoms)
(No Response)
Marvin JS


(c) N2H4
(No Response)
Marvin JS


(d) HClO3
(No Response)
Marvin JS
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5. –/1 points Chang12 3.Supp.7.009. My Notes
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Which of the following chemical equations is NOT balanced?
    


Solution or Explanation
Oxygen is not balanced. Coefficients of 2:25:18:16 would be needed.
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6. –/1 points Chang12 3.TB.006. My Notes
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The mass of 1.21 ✕ 1020 atoms of sulfur is
    
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