My daughter is taking an on-line chemistry class and needs some help with balancing equations.

 

Here's the problem:

 

What are the coefficients needed to balance the following equation?

 

MnO2 + NH4 --------> Mn2O3 + NH3 + H2O

 

Here are the choices:

 

a. 1,3 ------> 4,1,2

b. 2,1------> 1,2,1

c. 2,2-------> 1,2,1

d. 2,4-------> 1,2,1

 

Any help is greatly appreciated.

The answer would be C.

 

2MnO2 + 2NH4 --------> Mn2O3 + 2NH3 + H2O

This chemistry teacher agrees! :thumb:

Thanks, that's what she thought but wasn't sure.

This chemistry teacher agrees! :thumb:

I flunked Advanced Chemistry. :sssh:

C2H2Cl2 + O2 ---> CO2 + H2O + Cl2

 

Thanks, BF for the edit (how did you do that?)

 

She is really confused. Can anyone help explain the process?

C2H2Cl2 + O2 ---> CO2 + H2O + Cl2

 

Thanks, BF for the edit (how did you do that?)

 

She is really confused. Can anyone help explain the process?

To make the numbers small, just highlight the number you want to "shrink." Then use the "sizes" pull-down at the top of your posting screen to set the size to 1.

 

As for the equation, the idea is to balance the number of atoms of each substance on each side of the equation. If you have 3H2 on the left side and just H3 on the right side, you would need to add a 2 multiplier to the right side to balance it out.

OK, she got the part of using the 2 multiplier to balance C, but then got stuck on how to balance O.

OK, she got the part of using the 2 multiplier to balance C, but then got stuck on how to balance O.

I'm kind of struggling with that second one myself.

Where's the chemistry teacher when you need them?

I think this balances:

 

2C2H2Cl2 + 3O2 ---> 2CO2 + 2H2O + 2Cl2

She is off to bed. I will get her back on the computer tomorrow and hopefully she can get it so she can move on in the course. Thanks for your help.

She is off to bed. I will get her back on the computer tomorrow and hopefully she can get it so she can move on in the course. Thanks for your help.

It's like a puzzle. You just have to add to each side until everything equals out.

I think this balances:

 

2C2H2Cl2 + 3O2 ---> 2CO2 + 2H2O + 2Cl2

 

 

 

I think I see an error. You have 4 Carbons on the left and only 2 Carbons on the right.

 

How about this:

 

2C2H2Cl2 +5O2----> 4CO2 +2H2O + 2Cl2

How about this:

 

2C2H2Cl2 +5O2----> 4CO2 +2H2O + 2Cl2

That works.