Today was a hard day.
I was not a good teacher for my second year chem class. For some reason, my brain hit a wall when trying to describe a concept (relative rates of reaction) and I just could not come up with a good explanation. They're confused, frustrated, and tired. So am I. That's not a good mix.
This class waits for me to explain every single thing. Many have waited too long to start their final assignment and it's all hitting the fan with a test looming.
Are you looking for solidarity or suggestions?
We've all been there. I have suggestions, but maybe you just want to vent.
@MCDuncanLab I always have ears for suggestions 🙂
I've got some new models ready for tomorrow, but we're also going to have a talk about how to pace out work so it's not all happening at the end. They were given their practice set 10 days ago, many didn't take it out until today and felt stuck. One even criticized the class saying "nothing is connected and it's all just numbers."
That stung. But I reminded them that they waited until the day before a deadline to even look at the problems.
I think this is the first real unit where students feel truly challenged by chemistry. Bonding is hard because you have to memorize a bunch of stuff. Stoichiometry is hard because of procedures and math. Kinetics is hard because you need to know how everything _relates_ in a chemical system and use the math to back up claims about reaction mechanisms.
They'll be fine - but it is going to be a tough test for many and I wish today had gone better to help them prepare is all.
@brianb Kinetics is one of those topics I love teaching about in Gen Chem 2 at college, but I think it is the toughest topic for my students to master
I’ve been reading about your Iodine clock xpt - we used to do that, but I gave up 15yo and switched over to crystal violet & OH-. They still find it hard, but it seems to be more doable plus I like having them learn Excel and making the graphical plots that test 0, 1-, and 2-order kinetics.
I feel your pain but love your enthusiasm!
@QuantumDot2 this iodine clock works really well and gives reliable rate orders. I need to write up the procedure.
They're really struggling with relative rates of reaction. The biggest frustration is that they can't conceptualize why a higher stoichiometric coefficient leads to a lower rate when compared to others. Any tips?
For something like A --> 3B I'm going to try the language of "A is consumed at 1/3 the rate that B is formed" to see if that helps.
@QuantumDot2 I think the misconception is that they think that B is only 1/3 the rate of A and not the other way around.
@brianb My go to analogy is getting dressed:
2 socks + 1 pair of underwear —> …
And tell them that the socks get used up twice as fast as the undies in the morning. 😊 Ha ha - this stuff is just hard to wrap brains around without doing some hard thinking. Instant understanding is much rarer in this unit.
@brianb that you’re retrospecting this deeply after the fact is all I need to know. Your students will be alright. 👍
