BOOM!

Today we started off our class with Mr. Lieberman announcing that he had a demonstration for us. He filled up a can with methane gas (CH4) through a hole in the bottom and then lit it on fire through a hole in the top. We were told that the can would explode if his lovely assistant Colleen did her job right. Sadly, although Colleen did a wonderful job, Ethan was lacking in spirit and the explosion did not happen. So, Mr. Lieberman left the flame burning and continued on with his lesson.

Today's notes were on Stoichiometry. This unit combines our last two units of moles and chemical formulas and combines them. We can expect to have a quiz every day on what we learned the day before, unless Mr. Lieberman is feeling particularly generous that day.

Today's lesson, aka tomorrow's quiz topic, was about how to do the simplest kind of stoichiometric equation, in which a mole ratio is used to find out how many moles of one substance in a reaction is needed to form a certain number of moles of another substance in the reaction. To do this you must know the mole ratio of the two substances. This ratio is defined by the number of moles wanted/the number of moles given. To find these numbers, all you use is the coefficients from the molecular equation. The example we used in class was:

CH₄ + 2 O₂ → CO₂ + 2 H₂O

How many moles of methane are needed to make 13 moles of water?

To solve this you must multiply the desired 13 moles of H2O by the mole ratio of methane to water: 1 mole methane/2 moles water. The answer came out to be 6.5 moles of methane. These are the types of equations we had on our homework sheet and what we should expect to see on our quiz tomorrow...

BOOM!

I guess Ethan finally got a little faith...the paint can that most of us had forgotten about had exploded. The reason it took so long for the reaction to happen was because the can had to reach the proper ratio of methane to oxygen in order for anything to occur. Once it reached a ratio of 1 part methane for every 2 parts oxygen, it became a combustion reaction resulting in an explosion. (Sorry I didn't embed the video, I'm not great with technology.) Anyways, that was basically our day today, the homework was the sheet he gave us in class, the webassign if you have not already done it, and to be ready to take a quiz on mole ratio equations tomorrow.

ps. the next scribe is....Colleen C. Have fun!