Thanks so much sir for making these videos which are easy to understand and informative at the same time. They are not overly long and I really appreciate you cutting out the diagrams and colouring them in. That must have taken a while but it makes the question easier to understand for us. Thanks a lot.
Hello, I've literally spent all of today and yesterday watching all of your F325 videos. You've done a great job! Thank you very much. Will definitely recommend you to all my friends at school.
Hiya I have a question, at 8:32 the 6 x 10^-3 ions come from the manganate equation and not the S2O3 equation, therefore since it comes from the manganate equation you multiply by 2/5 to find the mols. If it came from the S2O3 equation, since the mols on the I2 have to remain the same, would you multiply by only 2 to get the mols of manganate? Or would you still need to multiply by 2/5, if this doesn't make sense I can reword it, I appreciate it may be a confusing read haha. Also, I have been watching you for ages, you explain everything in such an easily digestable manner! :)
Is it worth memorising all 3 redox reactions from the 3 Oxidising agents?(Cu2+, ClO- and IO3-) with Iodine ions? or will these be given in the question in the exam?
EpicEditsBySaz THIS is the question! Because if you look at the last qs on the June 2011 paper, you had to work out the ionic equation yourself- to get the stoichiometry-, and then calculate the percentage of copper in the brass.
Thank you so much! this topic has been very difficult for me but I finally understand I love your method of drawing it out to understand it easier. Thanks again! :)
@MaChemGuy Hi sir, sorry to bother you on the easter holidays but I really need help on a redox question and i cant ask my teachers since i cant email them over easter. Please can I have help. Question: To be safe, swimming pool water should contain 1grams-2grams of chlorine in every 1000dm^3 of water. In an investigation 500cm^3 sample of swimming pool water is analysed by treating it first with KI solution then titrating the liberated iodine against 1.5x10-3 moldm^-3 solution of sodium thiosulphate. 10.25cm^3 of Sodium sulphate is needed to reach end point. Would it be safe to swim in the swimming pool? And it gives you the thiosulphate ion half equation I did it and ended up with 0.7918g so not safe. But mark scheme says that its 1.09g but it has no working out to show how it got there. Please help!!
@MaChemGuy dont worry sir im an idiot and i fianlly go it after an hour of doing it. I was multipling by the wrong Mr I should be multipling by 71at the end to find the mass since its chlorine. I was using the Mr of ClO-.
I now know where I am going wrong! I also made the mistake of that molar ratio between the first equation and the second equation! I always tried to scale up the moles of I2, didn't realise it was the same.... :D
Thanks so much sir for making these videos which are easy to understand and informative at the same time. They are not overly long and I really appreciate you cutting out the diagrams and colouring them in. That must have taken a while but it makes the question easier to understand for us. Thanks a lot.
C'est Moi - You're very welcome and thanks for the kind comment, it means a lot
Best chemistry teacher on youtube !!!! Thank you so so so much!!
Eesh X Wow, that’s kind of you to say. Thanks!!
Hello, I've literally spent all of today and yesterday watching all of your F325 videos. You've done a great job! Thank you very much. Will definitely recommend you to all my friends at school.
I'm sure you get this quite a lot.
But you sir is a saviour to all Chemistry A-level students.
Please make some more videos mate!! They're proper helpful.
Hiya I have a question, at 8:32 the 6 x 10^-3 ions come from the manganate equation and not the S2O3 equation, therefore since it comes from the manganate equation you multiply by 2/5 to find the mols.
If it came from the S2O3 equation, since the mols on the I2 have to remain the same, would you multiply by only 2 to get the mols of manganate? Or would you still need to multiply by 2/5, if this doesn't make sense I can reword it, I appreciate it may be a confusing read haha.
Also, I have been watching you for ages, you explain everything in such an easily digestable manner! :)
thiosulfate titration had never been this easy. thank you so much!!!!!!!!
THE WHIK Glad you approve
Is it worth memorising all 3 redox reactions from the 3 Oxidising agents?(Cu2+, ClO- and IO3-) with Iodine ions? or will these be given in the question in the exam?
David Boakye Given in the exam 👍
MaChemGuy thank you! Your videos are such great help, they’ve made me improve so much
David Boakye That’s fantastic to hear. Thanks and good luck!!
do we need to know things like: IO3- + 5I- + 6H+ --> 3I2 + 3H20 off by heart
Thanks! When you finish the redox titration series can you do the " hard" topics please.
-_- If this isn't a hard topic I don't know what is haha.
Though I do get it now ance once you get it I suppose it's pretty simple.
Will they give us the equations? :(
EpicEditsBySaz THIS is the question! Because if you look at the last qs on the June 2011 paper, you had to work out the ionic equation yourself- to get the stoichiometry-, and then calculate the percentage of copper in the brass.
@2:53 how is the 2nd equation derived
Thank you so much! this topic has been very difficult for me but I finally understand I love your method of drawing it out to understand it easier. Thanks again! :)
Do we need to know the equations of the oxidising agents Cu2+, ClO-, IO3-????
thankss!!!! where is a good place to get questions (not p papers) for titrations?
do they give you the chemical equations in the exam?
OCR do. Not sure about other exam boards
Do you never scale between equations in redox titrations ?, do the calculated moles remain the same for the same species
Yes - mole ratios do NOT apply across different reactions.
you have taught me more in a 10 minute video than my actual teacher has this entire term , thank you 🙏
@@firminobecker7400 Too kind - it really doesn't need to be complicated. Thanks and good luck!!
Is this 100% on the new spec?
Definitely on OCR A
Thank you
Hello sir thanks for the video it really helped. Also , is the method always the same no matter what question they give you in the exam?
@MaChemGuy Hi sir, sorry to bother you on the easter holidays but I really need help on a redox question and i cant ask my teachers since i cant email them over easter. Please can I have help.
Question: To be safe, swimming pool water should contain 1grams-2grams of chlorine in every 1000dm^3 of water. In an investigation 500cm^3 sample of swimming pool water is analysed by treating it first with KI solution then titrating the liberated iodine against 1.5x10-3 moldm^-3 solution of sodium thiosulphate. 10.25cm^3 of Sodium sulphate is needed to reach end point. Would it be safe to swim in the swimming pool?
And it gives you the thiosulphate ion half equation
I did it and ended up with 0.7918g so not safe. But mark scheme says that its 1.09g but it has no working out to show how it got there.
Please help!!
@MaChemGuy dont worry sir im an idiot and i fianlly go it after an hour of doing it. I was multipling by the wrong Mr I should be multipling by 71at the end to find the mass since its chlorine. I was using the Mr of ClO-.
does the question normally give the ionic equation?
+Abul Shaher I tell my students to remember the thiosulphate equation. The other one is usually given
Is I2 moles always the same, regardless of the coefficients?
Shona Lambe Correct. Mole ratios apply across 2 equations
Do I need to know all these equation? Thanks so much for your videos. Literally so much easier than reading a textbook. You've helped me tremendously.
Tundé Sulaimon No, you'll be given them. Thanks, glad you like them :)
THANK YOU SO MUCH FOR YOUR EXERCISES!!! It helped a lot!
I now know where I am going wrong! I also made the mistake of that molar ratio between the first equation and the second equation! I always tried to scale up the moles of I2, didn't realise it was the same.... :D
very helpful thank you so much!
Thankyou soo soo much