Methanol Composition and Properties

This video tutorial explains how to find the percent composition by mass for each element in methanol (CH3OH). It begins with calculating the molar mass of methanol, which is 32.05 grams per mole. The tutorial then details the steps to find the percent composition of carbon, hydrogen, and oxygen in methanol. For carbon, the percent composition is 37.47%, for hydrogen, it is 12.61%, and for oxygen, it is 49.92%. The video emphasizes that the sum of these percentages should be close to 100%.

What is the chemical formula for methanol?

• CH3OH

• C2H5OH

• C6H6

• CH4

What is the molar mass of methanol in grams per mole?

• 28.02

• 44.01

• 32.05

• 18.02

How many carbon atoms are present in methanol?

• 1

• 2

• 4

• 3

What is the percent composition of carbon in methanol?

• 25.13%

• 37.47%

• 49.92%

• 12.61%

How many hydrogen atoms are there in methanol?

• 4

• 2

• 3

• 5

What is the percent composition of hydrogen in methanol?

• 25.13%

• 49.92%

• 37.47%

• 12.61%

How many oxygen atoms are present in methanol?

• 3

• 4

• 2

• 1

What is the percent composition of oxygen in methanol?

• 12.61%

• 49.92%

• 37.47%

• 25.13%

What should the sum of the percent compositions of all elements in methanol be?

• 125%

• 100%

• 75%

• 50%

Who is the presenter of the video?

• Dr. A

• Dr. D

• Dr. B

• Dr. C