## Exam

ran2000
Posts: 66
Joined: Fri Sep 28, 2018 12:15 am

### Exam

How do we determine the number of significant figures to use in the exam?

Lynsea_Southwick_2K
Posts: 55
Joined: Fri Sep 28, 2018 12:25 am

### Re: Exam

You look at the givens and determine the one with the least amount of sig figs. Your answer should reflect that number of sig figs.

Ex: givens 5.12345, .00000023, and .12.
The least amount of sig figs is 2 in .12
So your answer should have 2 sig figs.

Hope this helps.

904983525
Posts: 17
Joined: Fri Sep 28, 2018 12:26 am

### Re: Exam

Lynsea_Southwick_3F wrote:You look at the givens and determine the one with the least amount of sig figs. Your answer should reflect that number of sig figs.

Ex: givens 5.12345, .00000023, and .12.
The least amount of sig figs is 2 in .12
So your answer should have 2 sig figs.

Hope this helps.

Thank you for this. It really helped.

Henri_de_Guzman_3L
Posts: 88
Joined: Fri Sep 28, 2018 12:25 am

### Re: Exam

Dr. Lavelle has a great resource for sig figs on the class website. Here it is: https://lavelle.chem.ucla.edu/wp-conten ... OUT_SF.pdf

Chloe Likwong 2K
Posts: 70
Joined: Fri Sep 28, 2018 12:23 am

### Re: Exam

To provide more clarification:

Addition/Subtraction : The answer should have the "smallest number of decimal places."
For example: 10.2 + 1.005 + 2.35 = 13.555 = 13.6. (10.2 has one decimal present, thus, we "follow" it)
4.505 - 2.3 = 2.205 = 2.2

Multiplication/Division : One picks the least amount of significant figures.
For example: 2.3 x 3.570 = 8.211 = 8.2
1.3006 x 3.6 = 4.68216 = 4.7

As mentioned before, to acquire more info, just visit this : https://lavelle.chem.ucla.edu/wp-conten ... OUT_SF.pdf

Nina Do 4L
Posts: 61
Joined: Fri Sep 28, 2018 12:27 am

### Re: Exam

From my understanding, we will use the smallest amount of significant figures that is used in the problem for example, if the question gives us a velocity of 3.00x10^3 and energy of 1.2x10^-10, the smallest amount of sig figs would be 2 because 1.2 has two significant figures. Therefore, our answer should have 2 significant figures even though the 3.00 has 3 significant figures.

Nawaphan Watanasirisuk 3B
Posts: 58
Joined: Tue Nov 28, 2017 3:03 am

### Re: Exam

The "everything you need to know about SigFigs" section on Lavelle's website is really clear and helpful you should definitely check it out!