This video is incredibly useful! My teacher has never introduced me to the ICE method, and I can't understand why - it is so much less confusing than the way I was taught! Thank you so much for the video! :)
This is an excellent method. It is logical and clear and really allows us to see the molar changes of the chemicals in order to get an answer. Thanks :)
In the first example, wouldn't CH3CH2OH also be 0.575 as the equilibrium concentration same as CH3COOH??,, beacuse both have the same equilibrium moles and divided by 0.2, so should be the same value. ?
Just a quick question, I was under the impression that liquids do not affect equilibrium like aqueous and gaseous substances do and they're therefore omitted. If that's correct, why was the H20 concentration taken into account?
Moles of atoms and hence mass have to be conserved but not moles of molecules/compounds. Found this online to help explain. If I use a dozen eggs to make an omelette, in the end I have one omelette not 12. The mass of the omelette however will be the same as the mass of the 12 eggs. Hope that helps
Water is not always neglected from the equilibrium expression. If water is a solvent in the reaction, then you can neglect the water concentration term as it's in such large excess, its concentration is effectively constant. If water is not a solvent, then water term needs to be included. In the esterification reaction, water is being created in the process. Hence you need to include it in the Kc expression.
You're right. In this case you would get the same answer but not always (if there are powers in the Kc expression). If they give you the volume, they will expect you to convert the moles at equilibrium to concentration
Told it's 20% dissociated so there will be 80% undissociated. Starting with 1.0 mol means there will be 0.8 mol undissociated at equilibrium. Hope that makes sense
this is really helpful. you have clearly put alot of effort into this and it shows! you are a really good teacher!
alex h Really appreciate your comment - thanks
very helpful guides. I did not know about the ICE method, it really simplifies the whole question down, thanks.
I listened to this at speed x2 and i could still understand what you were saying hahaha
same 🤣😆
Same 🤣🤣😂😂
same
This video is incredibly useful! My teacher has never introduced me to the ICE method, and I can't understand why - it is so much less confusing than the way I was taught!
Thank you so much for the video! :)
This is an excellent method.
It is logical and clear and really allows us to see the molar changes of the chemicals in order to get an answer.
Thanks :)
Great video. Loved it. Now I'll get in A* in my A level chemistry exam tomorrow. Love from Pakistan.
This is gem for a person who don’t understand 2020 online classes of alevels.
Glad it's helped. Keep watching 🙂
my parents pay for a ridiculously expensive chemistry tutor for me but your vid has helped me more than she ever could
You can pay me back by promoting the channel and letting me know how you do. Thanks for your lovely comment and good luck!!
okay i'm gunna share your video on facebook, i know a lot of my classmates use youtube videos as well.
Thanks! Are you on Twitter, I am
yes! what's your username?
+Harriet Nicholls machemguy of course :)
I wasn't very good at working these calculations out but your explanation was really good :)
Thanks! Hope you can do them now!!!
didn't fully understand this method, until now! Thank you so much!
I lost the count of times how your explanation has helped me doing homeworks You really are an amazing teacher
And 6 years on your a life saver to me. Thank you so kuchen for making this video, I wish you were my chemistry teacher
Hi sir. Thank you for all your lovely explanations. They really helped me. you are an amazing teacher
Very kind of you to say so :)
thank you, you are awesome
u can not imagine how helpful this was
coco chanel Glad to hear it! Thanks for the comment, means a lot :)
fantastic job
This is really helpful, Thank God I found this video!
Done revising this chapter .Thanks so much
This is very easy to understand. Thanks so much 🙏
hi just a q, why are we using H2O in the equilibrium expression considering it’s a liquid.
very helpful regarding my exam
Really great revision video
You are simply the best
Well done you helped make my life barely any times easier :@
this is so useful, thank you!
In the last question, what would you do if you were not given the volume?
Hello how many significant figures or dp would you round the answer to?
Very helpful thanks a lot
In the first example, wouldn't CH3CH2OH also be 0.575 as the equilibrium concentration same as CH3COOH??,, beacuse both have the same equilibrium moles and divided by 0.2, so should be the same value. ?
Just a quick question, I was under the impression that liquids do not affect equilibrium like aqueous and gaseous substances do and they're therefore omitted. If that's correct, why was the H20 concentration taken into account?
Sounds like you're thinking about Kstab where the water is omitted
in the second example how can you have more moles total at equilibrium (0.8+0.4=1.2) than there were initially (1) ?
Moles of atoms and hence mass have to be conserved but not moles of molecules/compounds.
Found this online to help explain.
If I use a dozen eggs to make an omelette, in the end I have one omelette not 12. The mass of the omelette however will be the same as the mass of the 12 eggs.
Hope that helps
@@MaChemGuy ah okay, makes sense, thank you
LEGEND
Why was the water concentration used for this? I thought solids and liquids weren't used in Kc calculations
Water is not always neglected from the equilibrium expression. If water is a solvent in the reaction, then you can neglect the water concentration term as it's in such large excess, its concentration is effectively constant. If water is not a solvent, then water term needs to be included. In the esterification reaction, water is being created in the process. Hence you need to include it in the Kc expression.
@@MaChemGuy Would that be when water is labelled as an aqueous solution in the equation?
Typically do you know how many marks this would get you for the OCR A Spec (2021 Exam)
Around 5
Why do you need to divide all of the equilibrium moles by 0.2? It would have still given you the same answer anyway.
You're right. In this case you would get the same answer but not always (if there are powers in the Kc expression). If they give you the volume, they will expect you to convert the moles at equilibrium to concentration
+MaChemGuy Thank you, appreciate the content and your help
At the end of the video how did u find 0.8 for N2O4
Told it's 20% dissociated so there will be 80% undissociated. Starting with 1.0 mol means there will be 0.8 mol undissociated at equilibrium. Hope that makes sense
What the point in working out the change?
Some people find it helps
MaChemGuy okay thanks 👌
Aren’t you going to convert mol to molarity ?
I do in both questions. At 4:40 and 8:00
Kc calculations is f325 but nevertheless, it's still a great revision video for f325!
Hi can you explain how you know there are no units
Julia Onyebuchi You need to work them out based on the Kc/Kp expression
thank you
I love u
What aboot kp