Chemistry | Acids and Bases | Calculations

[@VuyokaziNgwane]

even in 2024 blessing you are thank you sir

[@MlungisiNkosi]

Thank you 🙏🏾

[@rudzanivincent2289]

Thanks you so much sir.. You make things easier... if you can be a teacher your children will always get 100% you make everything easy in both physics and chemistry.. thanks a lot

[@inspiringlounge3784]

That's what I also realized

[@MlungisiNkosi]

Thank you... I already am a teacher 😊

[@FellangMolefe-j2r]

​​@@MlungisiNkosiwhere do you teach I want to join your class

[@attiyahmemela7428]

😭😭😭Life saver.. Perfect timing.. Thank you sir

[@MlungisiNkosi]

You're welcome

[@mihlaliguga1698]

Keep doing the good work sir, this is very helpful as I prepare for the final exams❤

[@ofentseshilos5133]

Thank you so much Mr Nkosi, with your efforts we believe.....

[@MlungisiNkosi]

You're welcome Ofentse

[@amyy101k2]

You helped me for physics final and now ur helping me for the chemistry final (which I write tomorrow 😵) thank you so much!!!🤩

[@marypoppins9318]

Same lol

[@sazisomnyandu9546]

You're life saver Mr Nkosi, please keep them coming

[@MlungisiNkosi]

You're welcome. I will most definitely 😊

[@ThobaneMotlala]

sir..during neutralisation..are there any limiting and exceess reagent ..

[@phutireinette6581]

hi sir. what is the function of that burette?

[@rishongileshikwambani8215]

Sir why didn't you round off the value? 17:02

[@HomieIe-q9g]

Are we allowed to use ratio when we have concentration

[@okuhlenkosi6881]

Thank You So Much Sir. Your Efforts Are Really Appreciated.

[@MlungisiNkosi]

You're most welcome Okuhle

[@dineokatlego1712]

Thank you for your help, we would appreciate if you would make a video on auto-ionisation of water.

[@MlungisiNkosi]

I did touch on it a bit to explain Kw on acids and bases. Great suggestion nonetheless

[@FellangMolefe-j2r]

Is water a strong or a weak base

[@betfootballmastera2764]

Why do we always start to understand the work when we write the next day wow groot man you the best ❤ I appreciate it I know I'm gonna pass tomorrow 🎉

[@MlungisiNkosi]

That is awesome

[@jesykaob]

At 31:40, is it correct if H2SO4 could be broken down to: H2SO4➡H3O+ + HSO4- ? then we can the calculate the pH...

[@awolspizza]

nope, H2SO4 is diprotic. So it always donates 2 Hydrogens unless stated otherwise

[@ntethelelohlatshwayo6907]

You are the best sir

[@maokotokulogo866]

Siyabonga. Helpful

[@kaylasbeau6942]

I don’t understand the whole of question 8 on 8.1 on how you were working out the reactants it’s quite confusing. Is the any basic topic I can refer to and then come back to how you came about working all the reactants?

[@MlungisiNkosi]

Yes… Please check out the Playlist on Stoichiometry.

[@roshaanghani1709]

Sir at 1:15:47 why can’t we use the mass of 0.4 to get moles

[@MlungisiNkosi]

Because not all of the 0.4 grams is pure... The pure amount is the one that will participate in the reaction.

[@Asra_Fareed]

Hi! Great video😊 i would like to ask, at the time stamp of 30:05. Why didnt you round off your answer to 10,03% as it said so on the calculator, and dont the marking guidelines instruct that final answers should be rounded of to TWO DECIMAL places? Hope to hear soon What a great video 😍

[@MlungisiNkosi]

You’re right… Yes I should’ve neh.

[@noxolofarrar7381]

You really helping me as I'm about to write my finals thank you 🙏

[@MlungisiNkosi]

Super... I'm so grateful to hear that 😊

[@tamikharamchurran5740]

For the last question I used stoichiometry by using the mole ratio of H2SO4 and KOH then I calculated the no. of moles of KOH and used this to find the volume in dm3.

[@MlungisiNkosi]

That works very well 👌🏾

[@magautaraphahlelo9384]

Right in time 💃🏻thank u for deliverying

[@MlungisiNkosi]

Call me Mr Delivery 😂

[@magautaraphahlelo9384]

🤣🤣🤣🤣🤣🤣Ubereats

[@noluthandokhumalo8510]

Please help us with maths. Namely, trigonometry, euclidean geometry (part 2), financial maths and probability

[@MlungisiNkosi]

I wish you could've joined my online classes this past week. You may still join for the month though. Please send an email to [e-mail]

[@realsteez891]

At the last question you can also calculat the percentage purity then minus it from 100%, what remains will be your percentage impurity

[@MlungisiNkosi]

Correct ✅

[@MamudulaGhatsheni-vh1ms]

Why should we minus the impure and pure mass?

[@zaneleprincess333]

Thank you so much. You make every lesson easy

[@MlungisiNkosi]

You're welcome Zanele

[@neoKing01]

Very helpful video,,,, big thank you sir 🙏❤️

[@MlungisiNkosi]

You're most welcome

[@YtYt-x5k]

Sir. In the flask , there is 100cm3 of NaOH and only a little bit is neutralized..Would the solution still change colour even if all of it is not neutralized?

[@mahlatseagnes1534]

Sir plz fix the issue of the camera 😭😭😖we can't see the clearly

[@MlungisiNkosi]

This was recorded back in 2020 when I didn't have fancier equipment. Askies neh

[@KhozaSiyabonga-hn7kg]

Thanks Malume for the lessons 🤟🏼📚❤️

[@MlungisiNkosi]

My pleasure!

[@MamudulaGhatsheni-vh1ms]

Why did we subtract the pure mass from impure whereas from Rates we dont subtract ?Is it treated differently?

[@MlungisiNkosi]

The nature of the question required it…

[@MamudulaGhatsheni-vh1ms]

@@MlungisiNkosi Can you make me understand because I don't or is it because not all of the mass is bieng titrated hence you substruct?From the impure since since some in the impure is pure ?

[@dikeledisompane8900]

Is this question of calculations of ph part of gr 11 work 😅 or...

[@ian_sambo04]

16:58 sir i got number of moles as 3.3135x10^-3. is that correct or what?

[@MlungisiNkosi]

I think that’s fine

[@ian_sambo04]

@@MlungisiNkosi thank you sir.

[@dieumelamwenyi4762]

Thank you so much ❤

[@oneyy6165]

Oh so hydrolysis falls under the lowry bronstead theory?

[@MlungisiNkosi]

Yes it does

[@AndiswaShongwe-xm3fh]

Why do we change colume to Dm cubed if both volumes are in the same unit which is cm cubed?

[@AndiswaShongwe-xm3fh]

Volume *

[@lenanmalebana]

Thank you sir

[@godwillmbatha9248]

Thank u sir! Why did I've see this page now. Sir you don't say in class u have a youtube channel ! But thank u so much

[@MlungisiNkosi]

I did... Perhaps you were not there.

[@keirareddy84]

Heyyy can you please do a review of organic molecules before tomorrows paper

[@MlungisiNkosi]

I will do that soon

[@nomfundopearl4519]

Sir do you have a video for Ka and Kb❤

[@MlungisiNkosi]

Not yet… I will record it

[@lesegolekoko9203]

What if the ratio was 2:1 what would be the number of moles of the weak acid?????

[@MlungisiNkosi]

You would use the ratio to find the moles

[@sibusisoandile2597]

Eiii sir , can you also open a maths channel

[@MlungisiNkosi]

Will do...

[@mphonkwe2279]

this is ✨

[@MlungisiNkosi]

Awesome... I'm glad you found it helpful

[@tselamashinini1450]

Good day sir If u Said for 7.4) poH =-log(OH) =-log(0.11) =0.9586 PH +poH =14 PH=14-0,9586 PH =13.04

[@MlungisiNkosi]

Perfect 🤩

[@isabel.maredi]

Thank you so much

[@MlungisiNkosi]

You're most welcome. All the best for your exam tomorrow

[@phuti3031]

Sir I used the pure mass percentage then minused it from a 100 and got the same answer is that okay to do??

[@MlungisiNkosi]

That’s perfect

[@tlhokmokoena5396]

Hi sir when we write down the equations in an exam.Is it still right if we write down the arrow of the reaction without it being reversible like you didn

[@TshiamisoMaine]

Malume Mlungisi would I be wrong for 8.1 if I say Ph=-log[2H3O]?

[@MlungisiNkosi]

Yes it would be incorrect

[@nenekazimdluli9442]

So if I use the formula: pH= 14 + log [OH-]. Will I be penalised?

[@nonzukisobest3239]

YOUR HELP IS HIGHLY APPRECIATED .

[@MlungisiNkosi]

It is y absolute pleasure.

[@Roberto97810]

Meneer can you please try if you have some time to touch Doppler Effect and Rate and extent of reaction

[@MlungisiNkosi]

I've already covered Doppler Effect. Rate of Reaction is coming up next

[@Roberto97810]

@@MlungisiNkosi Dankie meneer big love for you sir

[@MlungisiNkosi]

@@Roberto97810 thank you

[@YtYt-x5k]

Sir please help me understand 1 thing. Does neutralization have levels? For example in a reaction , reactants need activation energy to react. Once they're past that level they have chances at colliding effectively. So for neutralization, if 15 cm3 of H2SO4 was added to neutralize an unknown volume of NaOH . If more than 15 cm3 was added , maybe 35 cm3 of H2SO4 , would there be more SALT and more volume of NaOH neutralized? And would the solution be darker in colour because a higher ratio is now neutralized? If you help me with this , my understanding would be 10× better .🙏🙏

[@MlungisiNkosi]

Please watch the acids and bases playlist…

[@kundaimaiwasha7391]

❤️

[@MlungisiNkosi]

That favourite heart ❤️

[@mamellothulo4603]

Sir can you please do Question 7 the chemical equilibrium questions 49:00

[@ndozadeswayersa607]

can you do Question 7 physical science p2 September 2020 Eastern Cape

[@MlungisiNkosi]

Noted

[@zanelemofokeng1119]

Thank you.

[@MlungisiNkosi]

Wola MaZ

[@liyemasibizo3529]

sad for me just saw the video now at 11:30

[@MlungisiNkosi]

You're on time... 😊

[@kiaranandkumar7726]

Me at 2:27am 💀😂💔

[@tshifhiwanems29]

@@kiaranandkumar7726 me at 04:37

[@thapelomorake8686]

- I'm still stuck on calculating the percentage of ethanoic in the vinegar 😭😭💔 I tried rewinding but still... 😪

[@MlungisiNkosi]

It is not an easy question this

[@oneyy6165]

That was a very tricky question 😂

[@nokhutulamadekufamba634]

Just on time thank you so much ✨

[@MlungisiNkosi]

You are so welcome

[@yofq4891]

I'm confident to walk on my chemistry exam tmr morning first thing

[@MlungisiNkosi]

I’m quite sure that you’ll do well…

[@2kaay_946]

shout out to those writing this tomorrow🤣🤣

[@MlungisiNkosi]

Woop Woop 🙌🏾

[@lulamalurh6112]

5.35 let say it's an acid that's strong and base is weak how it'll be?

[@MlungisiNkosi]

Please check under acids and bases, I covered that scenario already

[@taskeenhussain6304]

Life saver

[@MlungisiNkosi]

You are most welcome

[@Siphesihle_Dlamini]

I wish I found you earlier 😩

[@MlungisiNkosi]

Thank you for joining us eventually...

[@tjatuuapoleandritjikaka8082]

Thanks you sir but i can't see clearly 🙏🙏

[@MlungisiNkosi]

Sorry for that... Try to play the video at a higher resolution.

[@mahlatseagnes1534]

Ur camera sir 😭

[@MlungisiNkosi]

Askies what’s wrong?

[@mahlatseagnes1534]

@@MlungisiNkosi I cnt see...plz fix de issue of camera