Redox titrations

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  • Опубликовано: 9 сен 2024
  • You really can't avoid Titrations, not even at A2 level. This video looks at the Titration involving Redox reactions and will go through a worked example of potassium permanganate oxidising iron 2+ ions of how to calculate these mega mark questions complete with props!

Комментарии • 52

  • @yasminh
    @yasminh 6 месяцев назад +10

    how did you, in 12 mins, take something so scary and intimidating and break it down into easy to understand steps that I can actually do in my exam and aaaaa my mind is blown thank you so much

  • @3lackondabeat709
    @3lackondabeat709 5 лет назад +10

    I don't understand how you were able to construct the half equation. (before doing the + H20 then + H+ etc) simply how do we know to start with Mno4- ---------> Mn 2+ and Fe2+ -------------> Fe3+

  • @user-pn6eg9dy8s
    @user-pn6eg9dy8s 2 года назад +8

    You are so awesome, I use these videos to study for Caribbean Advanced Proficient Exams, the syllabus is really similar and you're a great help

  • @tommyroberts7167
    @tommyroberts7167 7 лет назад +35

    Gosh, this topic is really tough! But with your videos I am slowly getting there! Any tips on clearing it up? Thanks!

  • @paulvu7573
    @paulvu7573 7 лет назад +10

    thank you so much this was very easy to understand and very helpful, keep doing what your doing.

  • @riyaaaa56
    @riyaaaa56 Год назад +1

    ur saving my alevels thank you

  • @ismarikapandey3370
    @ismarikapandey3370 7 лет назад +7

    Does the oxidation of Fe always goes from 2+ to 3+ if originally it was 2+ as it is with the sulphate solution? If not or in other situations where there is unknown ions, what is the procedure to work out the change in oxidation states for unknown ions which are being oxidised in order to balance the equation?

  • @zannatul23
    @zannatul23 8 лет назад +5

    Excellent Video Sir

    • @AlleryChemistry
      @AlleryChemistry  8 лет назад +3

      +zannatul Zan Thanks very much! Please share the vid.

  • @yus_hijazi1858
    @yus_hijazi1858 2 года назад +2

    legend

  • @aviadottin7607
    @aviadottin7607 6 лет назад +1

    Thank you.This was very helpful

  • @martynasradzevicius9835
    @martynasradzevicius9835 5 лет назад

    I love you, thanks for the amazing and very useful video m8!

  • @ZiftTM
    @ZiftTM 8 лет назад +14

    I have a question, if you could respond that will help me very greatly!
    How did you know MnO4- would be reduced to Mn2+ and what the half equations were? In the question it didn't state how much it got reduced. This really is the only bottleneck for me, I don't know what the half equations are since surely it could be oxidized or reduced further? Thank you for taking your time to reply back if you do so! :)

    • @AlleryChemistry
      @AlleryChemistry  8 лет назад +6

      +Zift™ I reply to all comments I get through so that's lucky heh! That is a good question too. It always reduces to Mn2+ as this is the most stable reduced form of Mn. Mn4+ can form but is readily reduced to Mn2+ with any reducing agent present. The equation is a half equation and can be balanced using water, H+ ions and electrons in the normal way. I have a video on this that may be of use - ruclips.net/video/uFNAPXQXXNc/видео.html Hope this helps!

    • @ZiftTM
      @ZiftTM 8 лет назад +5

      +A Level Chemistry Revision Videos by Allery Tutors Thank you so much! :)

    • @AlleryChemistry
      @AlleryChemistry  8 лет назад +3

      +Zift™ No problem!

  • @yasheshmalik772
    @yasheshmalik772 3 года назад +1

    great video!!

  • @vampierjosefien
    @vampierjosefien 6 лет назад

    Thank you for making this video!!

  • @yeaminories8326
    @yeaminories8326 4 года назад +1

    How do we know which is oxidised and which is reduced??

  • @andreabaer6166
    @andreabaer6166 3 года назад

    cm3 is ml and dm3 is liters. moldm-3 is mol/L or M

  • @samtran8340
    @samtran8340 8 лет назад +5

    one quick question, how do I know when to multiply the moles of chemical in flask by 10 and when not to? I know this comes up in exam questions but I never know when to multiply by 10 and when I shouldn't. Thanks

    • @AlleryChemistry
      @AlleryChemistry  8 лет назад +1

      +Sam Kvon Yes if you are working out the moles or mass or concentration of a solution that was made in a flask and a portion of this was used in the titration then you multiply up. e.g. if you titrated 25cm3 of a solution that originally came from a solution in a 250cm3 flask, you need to multiply by 10 to find out the number of moles in 250cm3.

  • @asif7240
    @asif7240 2 года назад +1

    Thanks

  • @kotheralhumaidi4731
    @kotheralhumaidi4731 8 лет назад +3

    Brilliant video!!!!!!
    sir I have a question.
    An steel wire (steel is mostly iron) of mass 3.225g was dissolved in dilute sulphuric acid and the solution made up to 250 cm3. A 25 cm3 portion of this solution was further acidified and titrated against potassium dichromate (VI) of concentration 0.031 moldm-3. The volume required was 31.0 cm3. Calculate the percentage of iron in the steel wire.

    • @AlleryChemistry
      @AlleryChemistry  8 лет назад +4

      +Kother Alhumaidi Thanks! Your answer is 99.75%. I have the working written down on paper but I can't put the image on youtube. I can share it with you on twitter if you follow me @allerytutors Cheers!

    • @kushagrasharma6541
      @kushagrasharma6541 4 года назад

      @@AlleryChemistry Hi is there a way you could show me the answer too? I would really like to know.

  • @edenkathleen4718
    @edenkathleen4718 5 лет назад

    Thanks so much I finally understand it! Subbed :)

  • @user-vq4qy2hq5i
    @user-vq4qy2hq5i 8 месяцев назад

    How would you know MnO4^- was the charge on the ion in the half equation?

  • @ahmetlushi2009
    @ahmetlushi2009 5 лет назад +1

    Are all these videos for the AQA spec?

  • @packrat3213
    @packrat3213 5 лет назад +1

    You need a bigger white board

  • @faizahbegum5257
    @faizahbegum5257 4 года назад +1

    When writing the half equation for potassium manganate why don’t we add the potassium in the equation why is it just manganate and how do we know which is getting oxidised and which is getting reduced? Thanks

    • @faizahbegum5257
      @faizahbegum5257 4 года назад

      Or is potassium manganate always an oxidising agent

  • @mithanisalim
    @mithanisalim 2 года назад +1

    Very goooood

  • @qwerttttttttttty
    @qwerttttttttttty 7 лет назад +3

    Hi, thanks for the video. How would the situation change with waters of crystallisation, because some exam qs ive seen use this, eg. FeSO4.xH20?

  • @no-wm3sl
    @no-wm3sl 4 года назад +1

    how did you get mno4-

  • @melho.martinez761
    @melho.martinez761 5 лет назад

    Thank you! :)

  • @dno.16
    @dno.16 Год назад

    how can you tell whether it is MnO42- or MnO4-

  • @darkmoon3646
    @darkmoon3646 6 лет назад

    Thankyou soo much sir

  • @LassassinX
    @LassassinX 7 лет назад

    Can you tell me why the color change for this reaction is colorless to pink ? I dont get it ...? Cause MnO4- ions are purple and they reduce to Mn2+ which is usually colorless... Am i missing something ?

  • @user-mi8hj7pk3w
    @user-mi8hj7pk3w 6 лет назад

    I am 2 years late lol , but i am confused how did you know to use manganate ion and Fe , why not work out sulphate ion and potassium ?

  • @mmuk0705
    @mmuk0705 7 лет назад +1

    Thank you, this was so helpful! Just one thing- what did you say the colour change is for this titration? I missed it

  • @MissOghezi
    @MissOghezi 7 лет назад +1

    Hey Allery thank you for your videos :) Please could you tell me if iron is the reducing agent because potassium manganate is the oxidising agent?

    • @AlleryChemistry
      @AlleryChemistry  7 лет назад

      You're welcome. Yes iron would be.

    • @alicehardie5833
      @alicehardie5833 7 лет назад

      As a follow-up question can this be used to work out the concentration of any reducing agent? Provided you know the half equations so you know the molar ratios of the Manganate with the reducing agent?

  • @abla9991
    @abla9991 7 лет назад +1

    Where did the potassium go ????

    • @AlleryChemistry
      @AlleryChemistry  7 лет назад +7

      The potassium is a spectator ion and doesn't show in ionic equations as it doesn't react in the reaction. It's chemically unchanged

  • @victoryamadi9646
    @victoryamadi9646 5 лет назад

    I really thought you'ld actually demonstrate the experiment. Still helpful though. Thanks

  • @FardinShafi
    @FardinShafi 6 лет назад +1

    are you mr.hegarty? :/