Rate Determining Step and Reaction Mechanisms 1

[@HemZi123]

Thanks alot sir, I'd give you the nobel prize if I had one.

[@sarahkekeli]

Hello

[@HemZi123]

@@sarahkekeli hi

[@sarahkekeli]

@@HemZi123 any questions (examples) aside the ones he thought?
Even a video

[@HemZi123]

@@sarahkekeli sorry i can't even remember how to do these its been a long time

[@HemZi123]

@@JC-ij4kf almost finished :)

[@shazkhan5392]

Couldn't be more clear. Awesome clarity in your explanations. Thanks a lot.

[@binlo9959]

Wow, I've struggled with this all year but you've explained it so well that I've got it, thank you so much!

[@reizelangela]

thank youu!! please keep making videos! you're saving my dumb ass haha

[@zannatul23]

+Reizel Quiachon trust

[@cloudqbaby3101]

here in 2023, and thank you so much i swear you're a lifesaver

[@ummewaseem5983]

Would this be correct?NO2+NO2->NO+NO+O2 O2+CO+NO->CO2+NO2 overall: NO2+CO->CO2+NO

[@dobbythe1st]

thank you for these videos! would this be correct?
RDS- NO + NO ==> N2 + O2
OTHER - N2 + 2O2 ==> 2NO2
?

[@JimJam-ju6vn]

i got that, i wonder if it was correct

[@manalcheema8075]

This video is a gem thank you

[@MaChemGuy]

Very kind of you to say so :)

[@Charlotte-hf5jz]

in my answer, do i cancel out too or do i have to leave them in for the examiner?

[@cutieepie757]

wow excellent video

[@MaChemGuy]

cutiee pie Thanks!

[@omgoswamy9762]

Fantastic clarity

[@harveylloyd-williams3382]

you are a legend... 2020

[@MaChemGuy]

Harvey Lloyd-Williams I’ll take that. Thanks, very kind.

[@flowerpower487]

MaChemGuy
Sir please respond, can I have 1/2 N2 instead of just N?
Thank you for doing these videos.

[@thejibbos]

Yes, it's the same thing. Good luck for tomorrow.

[@flowerpower487]

thejibbos
Thanks brah, same to you of course, and thanks for clearing it up. :)
btw MaChemGuy is a king for doing this!

[@thejibbos]

Yeah he is the true MVP. How did you find the exam?

[@flowerpower487]

thejibbos
Easier paper than normal imo.
Got one exam left. wabu?

[@thejibbos]

I finished yesterday with f215. I thought this exam was 'easy' but it did have a lot of tricks in it.

[@alichopping2703]

Ok, so I've got r = k[NO2]^2, and the net equation is: 3NO2+O2 --> N2 + NO + 3.5O2.
"Propose a mechanism for this reaction"
Finding this example really hard, any chance you could shed some light on it?

[@MaChemGuy]

See my Twitter page. Two followers have answered it for you

[@Wallow28]

+MaChemGuy
This is my go as I don't have twitter.
NO2 + NO2 > NO3 + NO
NO3 + 2O2 > 0.5N2 + 3.5O2
0.5N2 + NO2 > N2 + O2
Cancelling out gives the overall equation of
3NO2 + O2 > N2 + 3.5O2 + NO
Out of interest, how difficult would you say this question is compared to the average past paper question of its kind?

[@sujata8957]

All makes sense now, you are the best!

[@nickeshaburke9836]

thanks a million, really helpful!!!!!!

[@nidhi_prem]

Thanks

[@RuhabDabeer]

I don't what is a rate determining step and how to figure it out

[@omgoswamy9762]

You make hard concepts easy

[@itsConnor28]

for the last why cant i have 2NO --> N2 + O2 & 2O2 + N2 --> 2NO2 ?

[@amirahrafique9408]

That's what I did too!

[@user-fn3up7rg6o]

Me three!

[@talhabashir873]

Me 4

[@belindamary7816]

Me 5?

[@a.a1061]

thank you so much

[@tahahussain5439]

sorry, just got a question in the first question example you said that the numbers present behind the reactant determine there order in the rate=k() however in the example of no2 you wrote second order whereas in the overall equation it is 1? can you please explain this to me? any one can answer!!!!! thanks

[@MaChemGuy]

The order tells you the number of molecules involved in the RDS not the overall reaction equation.

[@tahahussain5439]

@@MaChemGuy cool thank you very much and I love you videos sir keep up with the good work

[@ivanbliminse4325]

Thanks. Great video

[@theosims-woodhouse2446]

Would it be fine to write the N in the last mechanism as 1/2N_2?

[@MaChemGuy]

That would be OK

[@alevelsdemystified3410]

Awesome video.

[@zannatul23]

which method is better?

[@akifrahman]

for the RDS for the 1st one, cant you have NO2+NO2---> N204 instead of NO + NO3?

[@MaChemGuy]

JitteryRobin990 Yes as long as you cancel it in step 2

[@akifrahman]

@@MaChemGuy Thank you sir.

[@hxvoc_7708]

can you write 2NO2 instead of two separate NO2

[@MaChemGuy]

That’s fine 👍

[@rhenaldiwijaya7778]

Why cant the rate determining step be just 2NO2 rather than NO2 + NO2

[@chaabansa712]

Thanks boss man

[@Fienemien99]

How do you know what the RDS is?

[@MaChemGuy]

It's the slowest step and contains the chemicals that appear in the rate equation (nb if order 2 there will be 2 moles of them etc)

[@Fienemien99]

I realised that, but what if the rate isn't given? Than how can you tell which concentration (of which molecule) determines the speed of the reaction? Or is the rate always given?

[@MaChemGuy]

+Josefien Berg Never seen that before at A level

[@Blaze-ls3zw]

Josefien Berg I'm pretty sure the rate has to be given in a question, because rate can only be worked out through experimental data. It can't just be worked out theoretically. So you'll always have some rate measurements to start with, and then from that you can work out order, rate equation and etc...

[@pirlogarcia7091]

how come in the rate equations vid you said the coefficient isn't determined by the order but here it is

[@MaChemGuy]

pirlo garcia You’re mixing up the overall equation with the rate determining step equation.

[@thomashe529]

Who's watching in 2019

[@zahramalik7364]

bless u

[@khalidsamer2991]

bro can you come to his

[@khalidsamer2991]

EIS* (my school)