Lab 1 InLab - Reaction Stoichiometry 7/10/17, 4(29 AM
WebAssign Christopher Hill
Lab 1 InLab - Reaction Stoichiometry (In-Lab) CH 202, section 021, Summer 2 2017
Instructor: Lars Dunaway
Current Score : Due : Monday, June 26 2017 05:00 PM EDT
Override: 50
The due date for this assignment is past. Your work can be viewed below, but no changes can be made.
Important! Before you view the answer key, decide whether or not you plan to request an extension. Your Instructor may
not grant you an extension if you have viewed the answer key. Automatic extensions are not granted if you have viewed the
answer key.
Request Extension View Key
1. 4.78/5 points | Previous AnswersNCSUGenChem202LabV1 1.T.001.
Significant Figures Tutorial
Significant figures and decimal places play an important role in science because they are a proxy for
measurement precision. Chemistry, being an experimental science driven largely by precise
determinations of specific amounts, requires the use of precision in answering scientific questions.
The rules WebAssign follows are generally accepted and may even be spelled out in your textbook.
If you want to quickly go through this tutorial, use the "Skip" button at the end of each section.
However, if you use the "Skip" button you will not be able to go back and enter new or modify previous
answers.
If you want to practice a particular subject and check whether you completed the questions correctly,
use the "Submit" button at the end of each step.
Counts Have Infinite Precision
Rule 1: If you can count it, do not use significant figures or decimal places.
10 apples is exactly 10 apples, not approximately 10 apples, not 9 apples, not 11 apples.
Answering 10.0 apples is incorrect because it implies a precision that is not justified: counts have infinite
precision.
Enter the amount of apples. If you enter any value other than 10, it will be marked incorrect.
10
This question does not check significant figures. If your instructor enabled answer format tips, you saw
"Enter an exact number" when you clicked the answer box.
Check Where Needed
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, Lab 1 InLab - Reaction Stoichiometry 7/10/17, 4(29 AM
Rule 2: Significant figures are checked whenever you see the sigfigs icon .
Type "10." in the following answer box. The decimal point after the zero signifies your intent to give the
value to the ones-place. If you enter 10 or 10.0, your answer is incorrect because the question requires
you to enter your response with a precision to the ones-place (10).
(No Response)
If your instructor enabled display of the sigfigs icon, you saw beside the answer box.
If your instructor enabled it, you could click the icon to display information about Using Significant
Figures in WebAssign.
If your instructor enabled answer format tips and display of the sigfigs icon, you saw "Enter a
number with the correct number of significant figures." when you clicked the answer box.
Display of these clues is at your instructor's discretion, and none of these tell you how many significant
figures are required.
Non-Zero Digits
Rule 3: All non-zero digits are significant.
2.249 has 4 significant figures.
22.496 has 5 significant figures.
Suppose we have approximately 4.862 pounds of sugar. Enter the amount to 3 significant figures.
4.86 lbs
Enter the same amount to the tenth-place.
4.9 lbs
Zeros In Between
Rule 4: All zeros in between non-zero digits are significant.
2.049 has 4 significant figures.
20.006 has 5 significant figures.
How many significant figures are there in 58.005?
5
Leading Zeros
Rule 5: Leading zeros are not significant.
02.049 has 4 significant figures.
0.006 has 1 significant figure.
How many significant figures are in 0855?
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WebAssign Christopher Hill
Lab 1 InLab - Reaction Stoichiometry (In-Lab) CH 202, section 021, Summer 2 2017
Instructor: Lars Dunaway
Current Score : Due : Monday, June 26 2017 05:00 PM EDT
Override: 50
The due date for this assignment is past. Your work can be viewed below, but no changes can be made.
Important! Before you view the answer key, decide whether or not you plan to request an extension. Your Instructor may
not grant you an extension if you have viewed the answer key. Automatic extensions are not granted if you have viewed the
answer key.
Request Extension View Key
1. 4.78/5 points | Previous AnswersNCSUGenChem202LabV1 1.T.001.
Significant Figures Tutorial
Significant figures and decimal places play an important role in science because they are a proxy for
measurement precision. Chemistry, being an experimental science driven largely by precise
determinations of specific amounts, requires the use of precision in answering scientific questions.
The rules WebAssign follows are generally accepted and may even be spelled out in your textbook.
If you want to quickly go through this tutorial, use the "Skip" button at the end of each section.
However, if you use the "Skip" button you will not be able to go back and enter new or modify previous
answers.
If you want to practice a particular subject and check whether you completed the questions correctly,
use the "Submit" button at the end of each step.
Counts Have Infinite Precision
Rule 1: If you can count it, do not use significant figures or decimal places.
10 apples is exactly 10 apples, not approximately 10 apples, not 9 apples, not 11 apples.
Answering 10.0 apples is incorrect because it implies a precision that is not justified: counts have infinite
precision.
Enter the amount of apples. If you enter any value other than 10, it will be marked incorrect.
10
This question does not check significant figures. If your instructor enabled answer format tips, you saw
"Enter an exact number" when you clicked the answer box.
Check Where Needed
http://www.webassign.net/web/Student/Assignment-Responses/last?dep=16322173 Page 1 of 10
, Lab 1 InLab - Reaction Stoichiometry 7/10/17, 4(29 AM
Rule 2: Significant figures are checked whenever you see the sigfigs icon .
Type "10." in the following answer box. The decimal point after the zero signifies your intent to give the
value to the ones-place. If you enter 10 or 10.0, your answer is incorrect because the question requires
you to enter your response with a precision to the ones-place (10).
(No Response)
If your instructor enabled display of the sigfigs icon, you saw beside the answer box.
If your instructor enabled it, you could click the icon to display information about Using Significant
Figures in WebAssign.
If your instructor enabled answer format tips and display of the sigfigs icon, you saw "Enter a
number with the correct number of significant figures." when you clicked the answer box.
Display of these clues is at your instructor's discretion, and none of these tell you how many significant
figures are required.
Non-Zero Digits
Rule 3: All non-zero digits are significant.
2.249 has 4 significant figures.
22.496 has 5 significant figures.
Suppose we have approximately 4.862 pounds of sugar. Enter the amount to 3 significant figures.
4.86 lbs
Enter the same amount to the tenth-place.
4.9 lbs
Zeros In Between
Rule 4: All zeros in between non-zero digits are significant.
2.049 has 4 significant figures.
20.006 has 5 significant figures.
How many significant figures are there in 58.005?
5
Leading Zeros
Rule 5: Leading zeros are not significant.
02.049 has 4 significant figures.
0.006 has 1 significant figure.
How many significant figures are in 0855?
http://www.webassign.net/web/Student/Assignment-Responses/last?dep=16322173 Page 2 of 10
