AQA 2.5 Transition Metals REVISION

[@racheldoran9758]

Timestamps (for revising sub-topics): GENERAL PROPERTIES OF TRANSITION METALS (2.5.1) 2:50 = intro to d-block elements 3:34 = electron configuration of d block + defining transition elements 14:15 = general properties of transition elements 19:10 = introduction to complex ions ** LIGAND SUBSTITUTION REACTIONS (2.5.2) 21:18 = types of ligands 1:00:57 = ligand substitution reactions: small, neutral ligands (NH3) 1:03:12 = ligand substitution reactions: larger, charged ligands (Cl-) 1:04:44 = relative strength of ligands + the chelate effect 31:48 = haemoglobin ** SHAPES OF COMPLEX IONS (2.5.3) 23:17 = shapes of complex ions 39:23 = stereoisomerism in complex ions ** COLOURED IONS (2.5.4) 43:41 = d-orbital splitting 47:00 = ∆E=hν 48:14 = relating frequency absorbed to colour 51:30 = factors affecting ΔE and colour 54:04 = colourimetry 16:52 = colours of different oxidation states (to learn) ** VARIABLE OXIDATION STATES (2.5.5) 29:30 = calculating oxidation states of metals in complex ions 1:10:48 = vanadium chemistry: oxidation states 1:12:19 = vanadium chemistry: REDOX reactions 1:14:40 = redox potentials 1:19:39 = Tollens’ reagent 1:21:47 = redox titrations 1:26:00 = example of redox titration with Fe2+ ions and KMnO4 ** CATALYSTS (2.5.6) 1:29:18 = types of catalyst (homogeneous/heterogeneous) 1:31:12 = heterogeneous catalysis - e.g. the contact process 1:34:38 = catalyst poisoning 1:37:09 = homogeneous catalysis - energy profiles (+ example) 1:41:53 = autocatalysis

[@Avo12349]

Omg thank you,

[@hasili4413]

god blesss youuuu

[@rohitmakhloga8772]

legend

[@user-ui5ew]

Thank you sooo much

[@jbenson9942]

An absolute life saver!!🙌

[@dynamite2236]

Best human on earth this man is.

[@Tsy172]

Best Chemistry teacher on youtube u mean

[@losasakarosa9050]

I can't believe these are free, thank you so much!

[@AlleryChemistry]

No problem! Pleased you found them useful 👍

[@shaai4227]

@@AlleryChemistry Hi sir dow wee need to know the colours states at 1:03:07 and 1:04:23 ?

[@calaca55]

​@Shaai you only have to be able to describe and explain the test tube reactions for Cu^2+, Fe^2+, Fe^3+, and Al^3+ This includes colours + observations Edit: have a look at the specification for full details

[@kenziefisher911]

This video saved me I can't lie. This topic is one of the hardest, personally, and this video makes it so simple. Thank you so much.

[@moonlightmando7163]

I agree with you. Its the hardest one by far in my opinion.

[@ratofalady8125]

last minute gang wya ??? gonna cry fr

[@eems4565]

HERE i just pulled an all nighter nd i still dont know half the shit 😭😭😭😭😭😭😭😭

[@adailyfact]

What grade did you get

[@javhus100k3]

what grade did you get @@eems4565

[@neldino1251]

@@eems4565 what did you get in the end

[@juliaraliang5083]

1 day before exam, finally finish this shxt. this video saves my life

[@Rahhma]

i feel you lool. Learning this topic for the first time the day before, did not realise how much you need to memorise fml

[@adailyfact]

What did you get?

[@adailyfact]

@@Rahhma What grade did you get?

[@ella_mcgov2013]

Same boat one year later

[@NeoUno866]

This video is so great, I appreciate the references to organic chemistry, it really helps connect the related concepts!

[@georgiapactor4790]

Thank you SO much for these videos. I honestly do not know what I would do without them. I am self-teaching whilst working full-time so these videos really are saving me! Thank you again.

[@AlleryChemistry]

You're very welcome!

[@wtina3672]

This video is fantastic! i have recommended it to my friends !!! Perfectly match with our AQA syllabus

[@wtina3672]

Thank you sooo much sir !!!

[@katheriner6456]

HOW MANY OF YOU HAVE REALISED THAT YOU ARE LATE AFTER KNOWING THE AMOUNT OF CONTENT YOU HAVE TO MEMORISE? 😭

[@stellag9593]

Starting today for Monday 👍

[@njsmp1824]

i'm cooked

[@MK-sh7ol]

@@stellag9593 me too 😢

[@dionemuparadzi4223]

@@njsmp1824 its so over

[@koshikrubamoorthy7720]

@@njsmp1824yh I’m done

[@crylexion]

How do you finish a 2 hour video in 20 minutes?

[@samiultr]

Amazing video but quick error, your ethane dioate has a double C=C bond where it should be a single C-C bond

[@rosefagan2847]

Thank you so so much! This makes sense to me! Having not being in education for over 8 years this is so helpful and getting me back in to the swing of it

[@AlleryChemistry]

You're very welcome. Pleased they are helping to get yourself back up to speed. 😀

[@arnoacorhe6029]

Honestly this has helped me so much, was picnicking about how to revise properly and gather info for my revision, and your videos are the perfect tool for this, thank you so much for all of your videos, they really helped me out! 😁

[@AlleryChemistry]

You're welcome!

[@himikotoga8007]

POV: The night before the real exam be like:

[@Naomi.c773]

What did u get

[@lL-ci6kw]

What did you get

[@zn2319]

Me Rn!!

[@c00ldude94]

Ermm

[@adailyfact]

What did you get?

[@rosalina6677]

33:00 Those 4 Nitrogens come from a tetradentate ligand called porphyrin. If you say "haem" - that's the whole complex, not the ligand. As usual, your videos are super-useful! Perfect for a final cram for a topic test :)

[@antonia5565]

Thanks!

[@lexoticstudios5669]

almost like it doesn't make a single difference for the exam!

[@lorettakurtz1731]

Thankyou so much sir. Your videos are concise and very informative and the fact that you are actually enthused about the subjects (Contact process and autocatalysis...😀) makes them so much more interesting to watch!

[@AlleryChemistry]

Heh! I'm easily excited!

[@jameswhyte3834]

at 22:22 , the ethanedioate has a double bond between the carbons which i dont think should be there

[@archisketch6420]

The structure of Ethanedioate shouldn't have a double bond. 22:27

[@hannahmoomba5078]

none at all?

[@jafwonta]

@@hannahmoomba5078 c=c should be c-c. thats it

[@rv9051]

the main character in all of our stories

[@behappy1452]

ok...

[@FS-me8mj]

physics student must be feeling like a boss in this chapter

[@ahmedel-banhawy3169]

Why

[@bhavyaatibrewal5365]

@@ahmedel-banhawy3169 we do E = hf in physics

[@phillipschristian2]

At 1:22:50 you say that we're looking for the concentration of the reducing agent Fe2+, but then in the blue box you say we're looking for the concentration of the MnO4-? So which concentration are we looking for and were do we put that solution, and which one of the two is the reducing agent? (edit: think you just meant to switch around the MnO4- in the blue box and the Fe2+ so that it says "we look at finding the conc. of Fe2+ by titrating against an oxidising agent like MnO4-" ?)

[@ruthie1562]

I’m confused about this too!! I think we are finding out how much oxidising agent is needed

[@phillipschristian2]

Also, how do you know at 1:27:00 that Fe2+ is going to be the reducing agent and how do we know that Fe3+ is the ion of the Fe element that is going to form? Is that just something you have to learn or is that a part of just looking at the reaction and seeing what it's reacting with?

[@khash48]

Fe 2+ is a reducing agent, therefore it will get oxidised (loses electron) so it will go from a 2+ to a 3+ charge

[@Jaffa1002]

u have just clutched up and saved my alevel

[@SnowflakeMCPE]

To my future self: Revisit catalyst examples, colours of ions and the ligand types!

[@LeoAbraham-t9g]

At 26:21 arent the square brackets meant to cover the entire coordination complex instead of just the ligands

[@ruthie1562]

At 1:29:05 , I was confused as to where the 5 in the Fe2+ came from??

[@amyclabon4869]

You have to multiply it up to balance out the electrons

[@sarah5138]

at 31:21 how to we work on it the oxidation states of the ligands water or ammonia ??????????

[@yasminmohamed2674]

18:29 do we have to actually memorise the colours of all of these ions?

[@naomisimmons6512]

at 16:44, how come titanium isn’t in the table? Is there a chemical reason for this? Thank you :)

[@AlleryChemistry]

I assume you are referring to the colours.... If so then it's because you don't need to know about it for AQA.

[@naomisimmons6512]

Allery Chemistry okay great thanks so much!

[@mariammajid58]

at 1:27:02 how do you know how to balance the equation like that

[@krishthanki7777]

trust me fam

[@godislove.7421]

Too well explained 💕💕. Thank you!

[@AlleryChemistry]

You're very welcome! 😀

[@mnamna9039]

These are so helpful really appreciated

[@AlleryChemistry]

Glad you like them!

[@jpc47_13]

Its three days before paper 1 am i cooked?

[@shush6798]

just started today im finished

[@ethanl829]

im here the night before 🙃

[@Mmusa409]

Nope

[@lumosv1014]

Nah g still better than me

[@Apsjbfkks]

Lads 30 minutes until paper 1 let’s gooo

[@mrspedrix1858]

Do you need to know all the colours eith thr metals

[@Tristilax]

Great video- are we expected to memorise any equations for the catalysis section of the topic eg Contact process, Manganate autocatalysis, or the Iodide peroxodisulphate one ?

[@chunkyboimadu]

everything 😔

[@unimous]

Yes

[@asif7240]

This is amazing! Thank you!!

[@nafisac116]

I love you Mr. Harris

[@doseofpineapples1379]

Hi sir, thank you for making these videos. Is it a requirement that we memorise the colours of all the transition ions?

[@zek520]

Yes it could be beneficial knowing them

[@medicusv61]

22:59 Multidentate ligands shouldnt we define them as having more than 2 coordinate bonds so they are not mixed up with bidentate ligands?

[@winniethepooh8766]

bidentate ligands are multidentate ligands.

[@khash48]

hello, are we supposed to learn all the oxidation states and colours? thanks

[@AlleryChemistry]

Yes you need to be familiar with them

[@hannahrafique9537]

1:13:33 im confused about the equation to reduce vo2+, what acid is used, how come its 2h2o, and not just h2o and 2h+ on the left? please answer

[@xjn0177]

4 oxygens on the left and 4 oxygens on the right, its 2H20 to balance it out

[@smiles9882]

Thank you, genuinely thank you so much, I'm so tired, thank yoy

[@AlleryChemistry]

You're so welcome!

[@Mrh.h4ckz]

Damn, I live in the garage tho :(

[@devnayee]

Thank you for this video!

[@AlleryChemistry]

Glad it was helpful!

[@sharmi716]

Hi i would like to confirm at 43:28 if it's actually meant to be the 2 same ligands opposite to each other is a trans isomer, not 2 different ligands.Thank you.

[@lol.1296]

confused by that too

[@lol.1296]

ive already forgotten all I learnt so back and confused by that again😃

[@ImranAwan-n9s]

Do we need to remember the autocatalysis reaction examples?

[@saaemraza3934]

Plugged me nicely

[@iren6019]

quick question, in the redox titration questions in the exam, would we be given the equation for the reaction or o we have to work it out ourselves? Brilliant video, thank you so much for the revision !

[@MM-user2]

Sometimes they give it, sometimes they don’t. So it’s best to learn it

[@cecylishilling6837]

is there a mistake at 22 mins 58 seconds. the ethanedioate ion seems to have formed 5 bonds

[@MA-yu2ss]

Do we need to know about haemoglobin for this topic?

[@seray6942]

never seen a question on it, could come up tho

[@variant_1909]

the morning right before the real exam...

[@beezoid2479]

nice one mate

[@AlleryChemistry]

Thanks 👍

[@miinziiiiiii]

will we be given the delta E equation in the exam or do we have to memorise it?

[@ImranAwan-n9s]

Which of the reactions with colour changes are we meant to memorise?

[@ethangolin1289]

Ive heard that scandium actually is a transition metal becuase its atom has an incomplete d-subshell. Can anyone confirm what we need to know for AQA?

[@ImranAwan-n9s]

For the coloured ions in solution do we need to know all the colours, or just for vanadium?

[@nafeesa9098]

this was amazing thank you!

[@AlleryChemistry]

You're so welcome!

[@MohammedHussain-ss6kj]

how are you supposed to remember all of these chemical equations is there some sort of logic behind it where u can work out the products or is just something you have to memorise for example the variable oxidation state reaction for vanadium

[@MK-sh7ol]

Guys are we expected to know the colours at 1:04:20?

[@MK-sh7ol]

I thought we only needed to know the colours for the metal aqua ions

[@barnabasfuto7391]

Yes😢

[@User-t7i5z]

transition metals and aqueous ions are like the worst chem topics ;-;

[@missvardanyan1323]

Great vid but water is not replaced with oxygen. It’s gas exchange, it’s CO2 that is replaced

[@SJ_1970]

Actually he is correct. The AQA chemistry textbook says the same. The oxygen molecule replaces / substitutes the water ligand on the haemoglobin to from oxyhaemoglobin. When the oxygen reaches a place where it is needed, a water molecule replaces it and the process starts again. It's true that CO2 is lost in gas exchange, but this is specifically talking about the haemoglobin. CO2 doesn't bind to haemoglobin at any point. Hope that helps 😊

[@daniellenederpel916]

bookmark 34:00

[@mr.r2207]

doesnt haemoglobin bind to co2 instead of water?

[@mr.r2207]

Guys I just realised co2 binds to another part of haemoglobin which changes its tertiary structure to reduce affinity for o2, but you don’t need to know this for chem

[@fiya4444]

gl yall..

[@Masowe.]

anyone with an acronym for all these colours 19:15 ?

[@salmanamal2099]

53:19

[@ik5377]

Hi Sir, when writing the complex ion down, there are times where you put the transition metal in square brackets and other times where you do not. How do you know when to put the TM in square brackets and when to leave it outside?

[@cy5aAaAaA]

I'm pretty sure it has to be in brackets when the whole complex (metal+it's ligands) still have an overall charge that is not 0 so it's still a solution (aqueous). When the complex has a charge of 0 it's now a solid so you write it without brackets.

[@ik5377]

@@cy5aAaAaA 26:32 if what you're saying is the case, shouldn't the complex on the left have cobalt in brackets (since water is a neutral ligand)?

[@nasarafarah8966]

only put square brackets when the ion has an overall charge

[@p.n.archana2835]

YOU'RE THE BEST

[@whoneedsapillowwhenjinshou2660]

thanks for the vedio,i purple youuuuuuuuuuuuuuuuu

[@AlleryChemistry]

No problem 😊

[@amidiqbal7129]

From what minute does variable oxidation states start. Quick replies are appreciated please. Many thanks

[@Avo12349]

29:30

[@BotanTechHelp]

Do we need to know about Cobalt within transition metals for AQA?

[@Prashant-pm7iz]

no you don't need to know about cobalt chemistry. if you're still in doubt check the spec

[@456-s9j]

@@Prashant-pm7iz how about chromium?

[@BotanTechHelp]

@@Prashant-pm7iz Thanks a lot Prashant. Would you mind sending me the link to find the spec? I just want to be sure i'm looking at the correct thing. Thanks a lot

[@vishnumistry9098]

@@BotanTechHelp Section 3.2.5.2: Substitution reactions Substitution reactions involving Cobalt (II) were previously required knowledge under the old A-level Chemistry specification (2420). These reactions and the colours of the solutions and products are no longer required knowledge for the current A-level Chemistry specification (7405) - This was taken from an AQA sheet titled, Reactions of metal ions in aqueous solution

[@user-le3oy9gd2f]

Kinda confused on the colour part So when the light is absorbed the electrons excite then when they de-excite they release frequencies giving the substance colour. But then u also said that the light energy that is not absorbed is transmitted and gives colour So which one gives the colour? Thanks

[@seray6942]

all you need to know is that: the ion absorbs light energy/visible light the light that is reflected is the colour of the ion

[@aaimakhan224]

do we need to know the colours for all the transition metals??

[@calaca55]

Only conplexes of Cu^2+, Fe^2+, Fe^3+, and Al^3+ Edit: you need to know the colours of the vanadium ions and compounds too iirc Definitely check the spec for full details tho

[@haniahaq2827]

Hi Sir, thank you so much for the videos, they're so incredibly helpful. I just have a question about triangleE at about 46 minutes in: In the formula, triangleE represents the change in energy when light is absorbed right (I'm assuming, because data regarding light absorption is used)? But on the previous slide, triangleE represented the energy gap when ligands join. Are they the same thing (in which case I'm very confused) or does triangleE just represent two different things? If it's the latter, how do I differentiate between them? Please advise. Thanks again! Hania :)

[@danielwalsh.3835]

The energy gap is equivalent for both. If a ligand joins, the d subshell will split into two energy levels; I.e they have a difference in energy. The light energy required to move a ground state electron to the excited state is the same as the energy gap. By the way, for future reference, the triangle sign is delta, and just means a change in. Thanks, Dan.

[@sarimiari1389]

Legend

[@yaseen4878]

The goat

[@georgeashby4852]

Thanks

[@aaronferguson3749]

keep going!

[@abigailwright7251]

the square brackets are in the wrong place in octahedral complex shapes section (still good video though)

[@sarah5138]

what is it meant to be?

[@milanxoxoxo]

i love you

[@fortunateandinda5128]

Thanks sir for good work done

[@AlleryChemistry]

Most welcome

[@kayzi1757]

my goat

[@Utd101]

2.5.1 done 2.5.2 done 2.5.3 next

[@jennaaa-21]

anyone else cramming !!!!!

[@kingdomcitizen-4l]

the plug

[@aliciab385]

surely we don''t need to know cobalt or chromium colours and ligand substitution reactions ahh

[@Zen_Zen_Zense]

nahhh only the V ones

[@MA-yu2ss]

@@Zen_Zen_Zense do we need to know about haemoglobin for this topic?

[@lol.1296]

@@MA-yu2ss late but yes its on the spec

[@willollier8845]

anyone here the day before...

[@wooooo0oo]

ah im screwed

[@oo-mt5dc]

52:39