CALCULATE THE MASS OF ARBON (IV) OXIDE FORMED WHEN 3.0g OF CARBON ARE BURNT (C=12, O=16)

Question

YOU ARE TO CALCULATE THE MASS OF CARBON (IV) OXIDE FORMED WHEN 3.0g OF CARBON ARE BURNT HERE IS THE FORMULAR (C=12, O=16)

Answer 1

1) Write a chemical equation:

 

C + O2 → CO2  ( know this formula because O = -2 and 2 x -2 = -4, and -4 + 4 = 0, so it is CO2, not CO)

 

2)Balance the equation:

 

C + O2 → CO2  It is balanced.

 

3) Use this equation to derive the mole ratio required to perform the problem.

 

4) Begin with the given:

 

3 g C

 

5) transform g to moles using the molar mass from the PT:

 

3 g C x 1 mole C/ 12 g C

 

6) You are at moles!!!!  Ready for the mole ratio from the balanced equation:

 

3 g C x 1 mole C/ 12 g C x 1 mole CO2/1mole C

 

7) You are at moles of CO2!!!  Almost there!  transform mole to grams using the molar mass:

 

3 g C x 1 mole C/ 12 g C x 1 mole CO2/1mole C x 44 g CO2/1 mole CO2

 

8) You have arrived at the answer!  Solve for the final unit and number!

 

3 g C x 1 mole C/ 12 g C x 1 mole CO2/1mole C x 44 g CO2/1 mole CO2 = 11 g CO2

 

Answer 2

C + O₂ ==>CO₂ (note: CO2 is the same as carbon(IV) oxide)

moles of C used = 3.0 g x 1 mole/12 g = 0.25 moles C

Assuming there is sufficient oxygen (O₂) for complete combustion, i.e. that O₂ is not limiting, then...

moles CO₂ formed = 0.25 moles (there is a 1:1 mole ratio of C to CO₂ in the balanced equation)

mass of CO₂ from = 0.25 moles CO₂ x 44 g/mole = 11 grams