Today we’ll be covering the last topic of unit 2, Thermochemistry. Yes, it is exactly what it sounds like… Sort of. Thermochemistry may sound like its all about temperature, but really it’s more about the transfer of energy, specifically heat.
After today you will be able to calculate the amount energy (in the form of Calories or Joules) absorbed or lost when transferring energy, specifically heat. In order to do this, all you need to remember is a little song. Ahem…
“q” equals M-C-Delta t, M-C-Delta t. “q” equals M-C-Delta t, M-C-Delta t….
you get the point. The formula
q= m x C x /\t
is the formula for calculating transfer of energy.
- q is heat calculated in Joules or Calories
- m is the mass of the substance
- C is the specific heat (the amount of energy, in Joules or calories, it takes to raise the temperature of 1g of substance 1 degree Celsius) of the substance
- /\t is the change in temperature (t*final – t*initial)
The formula can be rearranged, like in math class, to get any of the variables alone to calculate one.
We’ll be starting some practice problems in class, then working on the rest tonight, and finishing up in class tomorrow before we start to review. The Answers can be found on the Semester 1 Docs Page.