24 October 2011

I love it when they get it

I introduced the Mole today in my Honors Chemistry class.  For those of you who don't remember HS chemistry, the mole is a generic term that represents a specific amount of a substance, specifically 6.02x1023 of a substance.  To put the size of this number in perspective, if you were to collect 1 mole of pennies and distribute those pennies equally to every human on the planet, each person would receive approximately one TRILLION dollars.  It's a lot of stuff.

My honors class is unlike any class I have in that they try to distract me from teaching by asking me complex questions related to the topic.  So, after I shock them with the above example, one student starts asking if you laid the pennies end to end, would it stretch around the world.  I said it would probably stretch around the world a few thousand times.  This answer was not acceptable for her so I told her to get the netbook out and look it up; Google the dimensions of a penny and the size of the Earth and figure out how many pennies you would need.  Just to prove me wrong, she rushes over, grabs the computer and is off working for the next 15 minutes.  (FYI, I was way off.  1 mole of pennies would wrap around the Earth approximately 899 TRILLION times)

After a few minutes I am talking about how to calculate the mass of 1 mole of a compound and a different student wanted to know how many moles of water are in a human being.  Not knowing how much water is actually in the human body, I told her (surprise, surprise) to Google it.  She picks up her iPhone and starts her search.  Unfortunately she ran short of time and energy before she could figure out an answer.  Turns out they only have percentages of water content listed on sites and not grams.  We needed a bathroom scale to actually measure someone's weight.  Guess what I am bringing in tomorrow!

I don't really care if they can calculate the number of moles of sodium in a sample.  What I do want is for them to be inquisitive, to know that they are free to ask questions, to know they are free to ignore me and work on something that has more meaning for them.  I want more days like today.