Skip to Content Go to sign in Skip to Primary Navigation Skip to Secondary Navigation Skip to Page Navigation Skip to Header Navigation Skip to Footer Navigation Read more about accessability options and our navigation

Physics Classroom is making strides to make our site accessible to everyone. Our site contains 6 navigation areas. The Primary, Secondary, and Page Level navigations have a screen reader version of their nav structure that allows using the left and right keys to navigate sibling navigation items, and up or down keys to navigate parent or child navigation items. The others can be navigated using tabs. The Primary Navigation handles the first 2 levels of site pages. The Secondary (which is not always available) handles the 3rd and 4th level of structure. The Page level navigation allows you to navigate the current page's headings quickly. The Header Navigation contains the Light/Dark Mode toggle, Search, Notifications and account login. The Breadcrumb Navigation contains the breadcrumb of the current page. If the current page has a breadcrumb, you can get to it by skipping to the content and tabbing in reverse (shift plus tab). The Footer Navigation contains links such as Privacy, Contact, about and terms. Some resources contain an Audio Player that can be activated by holding down the T key for 3 seconds, and then using K to pause and resume. While not every area of Physics Classroom is usable purely from keyboard and screen reader, we are committed to continue work on making this possible. If you have questions or need additional help, please use this link to contact us.

Return to screen reader navigation
Home Concept Builders Chemical Reactions Balancing Chemical Equations Help Help 15

Balancing Chemical Equations - Questions 15 Help

A balanced chemical equation shows the number of particles of each substance involved in a chemical reaction. Such an equation includes formulas and coefficients. The formulas include symbols for each type of atom in the substance. The coefficients are the numbers present in front of the formulas. The act of balancing a chemical equation involves selecting the lowest possible set of coefficients that would provide the same number of atoms of each element on the reactant and the product side of the equation.

There are two questions in this Question Group. The two questions are very similar or are of similar difficulty level. The question below is one of the questions.
 

Version 1:
Identify the lowest possible whole number coefficients that balance the chemical equation. Then conduct an atom count for each element.
 

CH3OH + O2 → CO2 + H2O

To be successful with this question, you need to know what a balanced chemical equation involves. You also need to have a good strategy for how to balance a chemical equation. Finally, you will need to make sure you know how to conduct an Atom Count. The two infographics below describe these three ideas. Study the graphics, giving particular attention to the Know How to Count Atoms, the Step-by-Step Balancing Method, and the Example sections in the second infographic. Some specific information regarding this question are provided after the second infographic.

 





 

Some Specifics About This Question Group

The two versions of questions in this Question Group are similar. They each involve combustion reactions. A hydrocarbon is reacted with oxygen; the products are CO2and H2O. There are three elements that must be balanced - C, H, and O. Since the element O shows up in two formulae on the product side, it would be best to start by balancing either C or H first. Balance one of these elements; then balance the other element. Once the elements C and H have been balanced, direct your attention to the balancing of O. This can be done by inserting a coeffiient in front of O2 on the reactant side. Finally, conduct an atom count to insure accuracy and completion.
Concept Builder Teacher Notes Directions