Pentane: Formula, Structure & Uses

Lesson Transcript
Instructor: Danielle Reid

Danielle has taught middle school science and has a doctorate degree in Environmental Health

Pentane, an organic compound, is commonly used to power vehicles. Explore the structure and formula of pentane and learn about its typical sources and uses. Updated: 11/02/2021

What Is Pentane?

This is an organic compound that gives power to cars and helps make polystyrene foam (those foam peanuts found in your favorite package). I am referring to our friend pentane. Pentane is an organic compound in the alkane functional group with 5 carbon atoms bound to each other with single bonds. The molecular formula for pentane is C5H12. Alkanes consist of only carbon and hydrogen atoms with single bonds linking them together. As an alkane member, pentane has the distinguished honor of being a simple organic molecule.

When you see the liquid form of pentane you may mistake it for water—that is until you smell it! Pentane is a colorless liquid that has quite the offensive smell. It has a melting point of -129.8º C and boiling point of 36.1º C. With such a low boiling point, pentane is able to evaporate (poof!) into a vapor very easily at room temperature. A highly flammable compound, if it mixes with air as a vapor it can be explosive. These extreme personality traits of pentane place it in the category of being volatile. In fact, because of these volatile outbursts pentane is classified as a volatile organic compound.

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Capillary Action of Water: Definition & Examples

You're on a roll. Keep up the good work!

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 0:00 What Is Pentane?
  • 1:23 Structure & Formula of Pentane
  • 3:26 Sources & Uses of Pentane
  • 4:20 Lesson Summary
Save Save Save

Want to watch this again later?

Log in or sign up to add this lesson to a Custom Course.

Log in or Sign up

Speed Speed

Structure and Formula of Pentane

As mentioned previously, the molecular formula for pentane is C5H12. Here are representations of the pentane molecule.

Pentane Stick Model

Pentane Model

The carbon skeleton looks like a stick drawing, and the 3-D image is show as different sized balls connected by sticks. As you can see, those 5 carbon atoms are present in a straight chain fashion. Remember, the single bonds linking carbon atoms to each other is what makes pentane an alkane.

Pentane has three different structural isomers. In other words, pentane has the awesome ability of camouflaging itself (without changing its molecular formula) into different structures. It can change into any three of these structural isomers or exist as a mixture of them. Those three isomers are n-pentane, 2-methylbutane (or isopentane), and neopentane (or 2-ethylpropane or dimethyl propane). Also, contrary to popular belief, cyclopentane does not have the distinct honor of being an isomer of pentane. This is due to the fact that the molecular formula cyclopentane is C5H10 which means that is has 2 fewer hydrogen atoms than pentane.

Now why would these structural isomers be important to remember? Believe it or not, physical properties such as melting and boiling point change from isomer to isomer. Would chemical properties of pentane change? I know you guessed this right; the answer is no. Remembe,r pentane's isomers only affect the arrangement of those carbon atoms. The arrangement does not change the number of carbon atoms or kind of atoms present in pentane.

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it now
Create an account to start this course today
Used by over 30 million students worldwide
Create an account