## How to find diameter from volume x length

Geometric formulae, word problems, theorems and proofs, etc.
macbluff619(1)
Posts: 1
Joined: Tue Feb 26, 2013 10:22 pm
Contact:

### How to find diameter from volume x length

The following question is in a chemistry textbook I have been using as a review. I'm 35 and not a student at any institution. Just trying to learn an interesting subject. I was able to answer every question from the first chapter except this one. Any help would be appreciated.

A 15.0-cm long cylindrical glass tube, sealed at one end, is filled with ethanol. The mass of ethanol needed to fill the tube is found to be 11.86 g. The density of ethanol is 0.789 g/mL. Calculate the inner diameter of the tube in centimeters.

11.86 g/0.789 g = 15.03 mL/cm^3. The length is 15 cm, how can I figure out the diameter?

Thank you.

jg.allinsymbols
Posts: 72
Joined: Sat Dec 29, 2012 2:42 am
Contact:

### Re: How to find diameter from volume x length

Maybe try first to find the radius of the cylinder.

You already found using the ethanol that the volume of this cylinder is 15.03 cubic centimeters. Using formula for volume of a cylinder,

$15.03=15*pi*r^2$

So just solve for r, and then for diameter, multiply by 2.