Chemistry HW help!

[chrizcrozz]

Hello! I perfectly understand that thee "answer" is not permitted to be given to me, but any walkthrough in helping me understand the question would be greatly appreciated! I'm taking chemistry online and have to read the text and understand the chapter independently and it's quite challenging! I haven't been able to find any example of the question in the text, I swear the chapter questions were made not even based on the chapter, LOL. But I really want to learn chemistry!!! HELP!

 

Here's the ?:

 

-Nail polish remover containing acetone was spilled in a room 6m x 5m x 3m, and 3600mg of the acetone evaporated. Calculate the concentration of acetone in units of micrograms per cubic meter. ?????

THANK YOU FOR ANY HELP!

 

Chriz

[KiriKat]

multiply the dimensions: 6m x 5m x 3m = 90m³

 

since 3600mg of acetone evaporated within the given dimensions: 3600mg/(90m³ ) = 40mg/m³ acetone

*3600mg/(90m³ ) means that 3600mg of acetone evaporated in a room that was 90m³ large.

 

I hope it helps.

Edited September 26, 2012 by KiriKat

[ACUV]

Hello! I perfectly understand that thee "answer" is not permitted to be given to me, but any walkthrough in helping me understand the question would be greatly appreciated! I'm taking chemistry online and have to read the text and understand the chapter independently and it's quite challenging! I haven't been able to find any example of the question in the text, I swear the chapter questions were made not even based on the chapter, LOL. But I really want to learn chemistry!!! HELP!

 

Here's the ?:

 

-Nail polish remover containing acetone was spilled in a room 6m x 5m x 3m, and 3600mg of the acetone evaporated. Calculate the concentration of acetone in units of micrograms per cubic meter. ?????

THANK YOU FOR ANY HELP!

 

Chriz

 

I'd first like to refer you to the following. There is a good page to have a look at. Physics and Chemistry are so intertwined.

 

http://www.bipm.org/en/si/si_brochure/

 

The following page is the webpage about prefixes.

 

http://www.bipm.org/en/si/si_brochure/chapter3/prefixes.html

 

The prefix for milli is ............................. m

The prefix for micro is .............................. μ

 

I would look at the answer to this question as being an AVERAGE concentration. There is not a perfect mixture of acetone in this volume. It is unevenly distributed.

 

There are 3600 milligrams of acetone in 90 cubic metres.

 

This is an average concentration of 40 milligrams per cubic metre. You require an answer that is in micrograms per cubic metre.

 

This is an average concentration of 40 000 micrograms per cubic metre.

 

 

 

 

 

[ewmon]

the "answer" is not permitted to be given to me, but any walkthrough in helping me understand the question would be greatly appreciated!

Chriz, you certainly are correct. Here's a more appropriate idea of a walk through —

 

They've asked for concentration in the unit of micrograms per cubic meter, which in simple terms is mass per volume. Whenever you see "per", it means "for", and its math equivalent is division. When they ask for micrograms (μg) per cubic meter (m³), what will be the unit for the answer? Next, find the mass involved in terms of micrograms, and find the volume involved in terms of cubic meters. Perform the division to obtain the number part of the answer, then join the unit designation to it.

BTW Chriz, I'll bet the chapter was on unit conversions, right?