Activity 1 1-18-11 Burning Candle Observations

What is burning? Show the chemical formula and an image of the structure.
Gases our burning. Our butane, CH3CH2CH2CH3, once given a spark will ignite and turn to flame if it has oxygen to burn. Then after you have your butane fire you turn it towards the wood and begin to try and start that on fire. It won't light at first because it is not hot enough to burn wood off turning it into a gas, as illustrated below.

 So only gases burn, and to get wood on fire you have to get it hot enough so that the wood starts to turn to gas, just like when you boil a pot of water to a certain heat and it starts to turn into a gas as parts of the water go shooting out of the pot into the air.

Write the chemical reaction.

 

So you take your fire, which in our case is C4H10 and not CH2O, but we are still burning a gas to make fire.

 

C₂₅H₅₂ + O₂ → CO₂ + H₂O

You burn the candle wax, which is the farthest to the left, and the burning also consumes oxygen. Water and carbon dioxide are both burned off from the fire and they are what is left.

Write the balanced chemical reaction.

 C₂₅H₅₂ + O₂ → CO₂ + H₂O unbalanced

C₂₅H₅₂ + 38 O₂ → 25 CO₂ + 26 H₂O balanced

I added 25CO2 to balance for the carbon on the left. I also had to add 26 H2O to the right to balance out for the H on the left. Then I added 38O to the left side to balance out for the new C and the new H to the left side, and now we have a balanced equation where we burn off as much stuff as we put in, because matter just doesn't disappear.

This is the balanced chemical reaction for when you burn butane.

2C4H10 + 13CO2 --> 10H2O + 8CO2

 

 I added a 2 to the first C4H10 because when balancing I would have been left with a half, which isn't possible, and I added a 2 so the half would become a whole.