Homework answers / question archive / CH110/120 Assignment #3 Version A General Instructions   Due Date: October 6, 2020, 11:59 pm in the folder on Gradescope that corresponds to your version of the assignment

CH110/120 Assignment #3 Version A General Instructions   Due Date: October 6, 2020, 11:59 pm in the folder on Gradescope that corresponds to your version of the assignment

Chemistry

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CH110/120 Assignment #3 Version A General Instructions

 

Due Date: October 6, 2020, 11:59 pm in the folder on Gradescope that corresponds to your version of the assignment. Please see below for the late policy.

Value: 6.5% of your final grade

 

1. There are four versions of this assignment; you can choose which version you would like to submit. You should submit only one version.

 

2. Write your student number on each page of your assignment.

 

3. You must submit your assignment to Gradescope as a .pdf. Please review the instructions for how to submit an a .pdf assignment. There are also instructions on MyLS for how to convert images to a .pdf if you need to do so.

You should answer questions using the formatting that has been provided. There several ways that you could do this:

1. You can print the assignment, complete it on paper, and then follow the instructions in the Gradescope folder on MyLS to take a picture, save as a .pdf, and upload to Gradescope.

 

2. You could do your work on paper, take a picture, and insert the image in the Word document. You can save this document as a .pdf and upload to Gradescope.

 

3. You could do all your work on your own paper (no printer), and then follow the instructions in the Gradescope folder on MyLS to take a picture, save as a .pdf, and upload to Gradescope.

 

4. Students with tablets may want to fill out this document on their device, convert it to .pdf, and upload to Gradescope.

 

4. You must show full work (include units) for your problems. You do not need to show how you calculate your molar masses (but be careful that you calculate them correctly). 

 

5. You are permitted to use your textbook and other course resources (MyLS) and to talk to your classmates about this assignment, but your submission must be your own individual work. You should not copy the work of others. You should not share your work with others. You should not accept help from others who want to send you their work.

 

6. You are required to sign the Academic Integrity Pledge at the end of the assignment.

 

Academic Integrity

It is expected that all students will follow assignment instructions and will adhere to Laurier’s regulations with respect to Academic Integrity.

The following violate Laurier’s Academic Code of Conduct:

1. Posting assignment questions to message boards, social media, or other unauthorized websites (ex. Reddit and Chegg). These questions are the intellectual property of your course instructor, and you do not have permission to share them outside those registered in our class.

 

2. Posting assignment answers in virtual "course groups" (ex. Facebook, Discord or WhatsApp). While you can discuss problem solving strategies, it is expected that you will carry-out the problem solving independently.

 

3. Sending your work to other students. You are not permitted to send your assignment solutions to another student. Your course instructor understands that you might be doing this with the intention of helping a classmate, but this kind of “help” directly violates Section 4.01 of Laurier’s Academic Code of Conduct: misconduct is an act by a student, or by students working on a team project, which may result in a false evaluation of the student(s), or which represents an attempt to unfairly gain an academic advantage, where the student either knew or ought reasonably to have known that it was misconduct.

 

Your course instructor takes academic integrity seriously (because in science, it can have serious consequences for many people). If you have questions about how to conduct yourself when completing course assessments, you should contact your course instructor for guidance.

Late Policy

 

This assignment is due on October 6, 2020 at 11:59 pm in the folder on Gradescope that corresponds to your version of the assignment.

Assignments submitted during each subsequent hour after the due date/time will be subjected to a 10% late penalty.

For example, if you submit your assignment at 12:03am on Oct. 7, the highest grade that you will be able to achieve on this assignment is 90%. If you submit your assignment at 1:03am, the highest grade that you will be able to achieve on this assignment is 80%.

At 9:00 am on Oct. 7 your assignment will be worth 0% and will no longer be accepted.

Do not wait until 11:59 pm on Oct. 6 to submit your assignment.

Specific Assignment Instructions:

 

1. Your student number has nine digits: 123456789. Replace the numbers that are bolded and highlighted in yellow with the corresponding value from your student number. For example, if your student number is 009820864, then:

 

0.123 mol/L = 0.009 mol/L (this means that 1, 2 and 3 refer to the 1^st, 2^nd, and 3^rd digits in your student number)

0.456 mol/L = 0.820 mol/L (this means that 4, 5 and 6 refer to the 4^th, 5^th, and 6^th digits in your student number)

7.89 x 10² mL = 8.64 x 10² mL (this means that 7, 8 and 9 refer to the 7^th, 8^th, and 9^th digits in your student

                                                                                                                                                                     number)

If you do not understand this instruction, email your instructor with your student number and the version of your assignment, and your course instructor with clarify these requirements.

 

2. For Q1, you are expected to identify at least four problem solving strategies used in arriving at your answer. The in-class problems from September 18 can be used as an example. You are not required to do this for Q2.

 

3. For Q1 you are required to identify a relevant course learning outcome. These can be found at the end of your syllabus. Please do not make up your own learning outcomes. You are not required to do this for Q2.

 

4. At the end of your assignment, you must rewrite and sign the Academic Integrity Pledge.

 

 

 

Q1) The thermite reaction has been used in welding (especially in welding railway tracks) and to isolate iron. It proceeds according to the following:

_____Fe₂O₃(s) + ____Al(s) à ____Fe(s) + ____Al₂O₃(s)

(a) Write the balanced molecular reaction. Include phases.

(b) For this reaction, at 298 K, DH^o = -852 kJ/(mol Fe₂O₃). If 4.56 g of Fe₂O₃ react with 7.89 g Al(s) at constant pressure and 298 K, how much heat is evolved? Show full work and include units with all numbers.

(c) If all the evolved heat from part (b) goes into melting solid water (ice) at 0.0 ^oC, what mass of ice can be melted? Assume that no temperature change takes place for H₂O.

 

Your student number
Problem solving strategy	Problem solving
State one learning outcome achieved from this activity.

Q1=4 points                                                                                                    Insert extra pages if required.

 

 

Q2=2.5 points                                                                         Student number:

 

Q2) (a) A gas is compressed from a volume of 9.67 L to 6.78 L by an external pressure of 3.00 atm and at the same time loses 175 J of heat. Calculate DU of the gas. 1 L atm = 101.33 J (Note that only the highlighted decimal values must be replaced with the corresponding values from your student number.)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Q2) (b) Use the standard enthalpies of formation from Appendix IIB to determine DrH^o for the complete combustion of acetone or propan-2-ol.

 

Hint: Appendix IIB has been provided under “Course Information” on MyLS. It is recommended that you follow example 6.12 in your text to show work for your solution.

 

Your compound

Formula

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Integrity Pledge

“I affirm that I have not given or received any unauthorized help on this assignment, and that this work is my own.”

Rewrite the above statement in the following box and then sign and date below.

 

__________________________________________                                    _______________________

Signature                                                                                                         Date