Percent Composition Cartoon
Updated: 7/23/2020
This storyboard was created with StoryboardThat.com

By Viraj Sharma

#### Storyboard Text

• One day Mike was wondering how to calculate percent composition by mass. He decided to ask his science teacher after school to help him
• Mr. Obert, I was wondering if you could teach me how to calculate percent compositions?
• Of course! Let me give you a lesson on percent composition!
• Awesome! Thanks!
• ﻿.
• Let's look at the whiteboard here. Remember that the molar mass represents 100% of the mass of 1 mole of a substance
• I have written the formula on the board for calculating percent compositions. It's completely fine if you don't understand it the first time
• mass % = mass x 100%
• ﻿______________
• ﻿Total mass
• _________________ __________
• Next, we find the molar mass for the entire compound, so we look up the molar mass for oxygen, which is 16.000g and when added with hydrogen, the total molar mass is 18.016 g. To determine the percent of Hydrogen in water, simply divide the molar mass of hydrogen by the total molar mass of water and multiply by 100%. So, hydrogen makes up 11.19 percent of water
• We first look at hydrogen on the periodic table. The molar mass for hydrogen is 1.008g. However there are 2 atoms of hydrogen, so the total molar mass is 2.016.
• ﻿.
• To calculate the % composition, we calculate the percentages of each element in the compound by mass