I love your videos, they are so helpful! But when you recommend watching a previous video before hand, please can you link it in the description, it would make finding it so much easier
wow this is so helpful your work is just amazing you teach me more in these 4 minutes than my teacher that teaches for an hour . keep up the good work your amazing ! quick question by when will all the paper 2 videos be done
I don't understand why you need the other known food coloring that the unknown sample might contain in the first place - I mean, in both scenarios, whether we add the known food coloring or not, we still measure the Rf factors to find which substances the unknown food coloring sample contains. What am I missing? (Btw, great videos, extremely informative and to the point).
So yeah just had an idea to comment on a video I just got back from school kinda tired got my new phone.anyways come back when it's Yr gcse remember I was in this moment
I'd be surprised if it wasn't given in the exam but the honest answer is that they could expect you to remember it. Remember that it cannot be greater than 1.
Idk if this will help u but the Unknown substance separated into three dots and each of the spots line up with the spots at A, C and D therefore it is likely that the unknown substance contains the pure substances A, C and D of course we don’t know for sure because they could be coincidentally the same and be different substances so you can check they are the same substances by testing it with different solvents and calculating the rf value Hope this helps!
Hi. That's the chromatography video for paper 1 (in Separating Mixtures). The chromatography video for paper 2 is in the Chemical Analysis playlist. You'll see that includes the stationary and mobile phases.
If it only has one colour after chromatography then it is pure. Pencil does not dissolve because it is made of graphite which is a giant covalent molecule and is insoluble in water.
In this example since the unknown substance splits into substances that line up with A, C and D we can work out that the unknown substance contains A, C and D
@@Freesciencelessons I dont get this. if we remove the chromatography paper when the solvent is around 3/4 up the paper, wouldnt it affect our Rf value. Because if we wont always be dividing the distance travelled by the substance by the same value, (if we can decide when we stop the experiment), wouldnt the Rf value change?
so say we remove the paper when the solvent has travelled 10cm, and repeat the another group removed the paper after the solvent has travelled 15cm, wouldnt the Rf value be different.
Despite of the crisis of Coronavirus, I am here to revise on the bright blue screen. 👌
U yr 11 or 10?
If i get one more head space advert I’m going to uninstall my GCSE’s
ikr, same ad every vid
ps: nice profile pic, mine is the same but zoomed in
adblock works on youtube
@@Motherforker-c2o ikr it's the best thing on the planet
@2-0 u still get those they are SO annoying
Simplypiano TOO MUCH SIMPLY PIANO
This guy just needs to replace all my teachers
So true
Sean>reading through year 10 exercise books
I love your videos, they are so helpful! But when you recommend watching a previous video before hand, please can you link it in the description, it would make finding it so much easier
true i was looking for a comment like this lol
@@Nilashaaaaa he tells you the playlist - you can find it on the front page
@@dmf19 i cant fid it please link it
year 10 mocks tomorrow... had to get some revision in and this wonderful man is coming in clutch again!
hows year 11 going
hows year 12 going
hows year 13 going
How's life going
how's uni goinggg
Only reason I didn’t fail my biology exam is because of this channel.
Chief K no
@@isaacbarnett3179 yess this channel is awesome
g this chemistry
@@ayuba3282 im dead
@@ayuba3282 Sean is so smart that his chemistry videos will help you ace Biology.
Hi I’m just wondering why don’t you do the smile any more
Wolf Meister's 100 things are serious
these days
Things are real serious now, less than 2 months left, aaahhh!
thx for this my gcse is tmrw
wow this is so helpful your work is just amazing you teach me more in these 4 minutes than my teacher that teaches for an hour . keep up the good work your amazing !
quick question by when will all the paper 2 videos be done
how did gcses go lol
@@rossjago2381 🤣🤣🤣🤣
Very convenient as this channel helps me to create my revision cards. thank you.
hey thanks for the video my exam is in ten minutes at it helped me so much ! you are a legend sir
2024 anyone?
Late revision, gcse chemistry exam in 2 hours 😂
And you're still writing and checking comments instead of revising🤣...(the comment 2 years ago but anyway..curiosity)😂
It’s 1 am and it’s Monday I have a test tomorrow I am just revising before sleep 01:00
@@sassy__diaryrose3067 you think he past
exam in 40 mins good luck those in 2020
this aged well 😳 howd it go ??
Last chemistry video ever, thank you sir 🙌
2019 anyone?
Nah I’m from 2067
Jacob Dobrin Urm hour before the exam?
Jacob Dobrin today😂😂
Jacob Dobrin oh shit he we go again
2022
holy... tysm I never understood chromatography at school
your greenscreen is really good
My chem exam is today, hoping it goes well 😊
THANK YOU MR SCIENCE MAN!
Very helpful, many thanks!
Freesciencelessons, hi sir just wanted to know what you would say the IV, DV and CV are in this experiment or if anyone else knows. Cheers.
Certain practicals do not have IV, DV and CVs. I would say that includes this one.
Independent variable: ink used
dependant variable: distance moved by substance and distance moved by solvent
a control variable: amount of ink used
I don't understand why you need the other known food coloring that the unknown sample might contain in the first place - I mean, in both scenarios, whether we add the known food coloring or not, we still measure the Rf factors to find which substances the unknown food coloring sample contains. What am I missing? (Btw, great videos, extremely informative and to the point).
Last minute revision for 2019 chemistry paper2
Us this required practical on chemistry paper 2 higher combined aqa??
yes it is also on AQA's adance topic information notice as a required practical
Thank you so much kindly Sir! I have my Chemistry Paper 2 tomorrow. Anyone else like me?
watching this before the chemistry gcse tomorrow
thanks you are the best teacher ever there should be an award
do we need to know the equation if you're doing foundation
did u need to know it in the end?
Last minute required practical revision right here
3:38 will this equation be given or do we need to know it?
Need to know it g
Freesciencelessons do we have to remember everything word for word to learn the practical
So yeah just had an idea to comment on a video I just got back from school kinda tired got my new phone.anyways come back when it's Yr gcse remember I was in this moment
Banger vid bro 💪💪👍👍🔥🥶🥵🥶🥵
If you were trying to find out the Rf value of an impure substance, which spot would you look at to find the distance travelled by substance?
You'd need to do it for each spot and identify each substance.
It's worrying how there aren't many comments from people from 2019.
this channel has saved me idec
Please do a video about acids and bases
Nice tie
is the Rf value given in the paper or will i have to learn it?
you calculate it by using the equation he gave
You need to know how to calculate RF value which is distance traveled by spot/ distance traveled by water.
sometimes AQA gives it to us but perhaps try to learn it before today's exam
Are required practicals the same for all exam boards?
You can find your exam board’s required practicals in the spec
Is the Rf value always calculated in mm? Or in cm too?
as long as both the top and bottom values are both mm or both cm not a mix.
Do we need to know the Rf equation or are we given that in the exam?, Love your vids btw!
I'd be surprised if it wasn't given in the exam but the honest answer is that they could expect you to remember it. Remember that it cannot be greater than 1.
Thank u. U helped me alot
hi can i ask an a level question? what are bicomposite materials?
Awesome work, really helpful! Keep it up!
better late then never 💪🏽
2:48 someone help i dont understand this part
Idk if this will help u but
the Unknown substance separated into three dots and each of the spots line up with the spots at A, C and D therefore it is likely that the unknown substance contains the pure substances A, C and D of course we don’t know for sure because they could be coincidentally the same and be different substances so you can check they are the same substances by testing it with different solvents and calculating the rf value
Hope this helps!
How can you tell whether a substance is pure or not?
Sir when will you make the practical video of water purification ?
Do we need to know this method because in the revision guide there isn’t a method
Yes definitely. It's a required practical and I use the method described by AQA in its required practical handbook.
Freesciencelessons Thank you xx
Hello sire, are the 5 dots pencil or a colour cos u said pencil in video and then colur
No the line is in pencil. The dots are ink.
2023 gang who’s here ?
Yep
Chen today 😭
*chem
@@samirmaharaj5917 chem p2 tmrw
Meee
How would the water move up all the way there
If a mixture is made up of more than one chemical, how do you calculate the overall rf value of the mixture (e.g. a spot of ink)?
If the questions asks to find the Rf value to the furthest dot just do what Mr Shaun did
Dear Sir, you have missed the stationary and mobile phase in this chromatography video!
Hi. That's the chromatography video for paper 1 (in Separating Mixtures). The chromatography video for paper 2 is in the Chemical Analysis playlist. You'll see that includes the stationary and mobile phases.
Love this mate
absolute mad lad
Shaun Donnelly for Smash Bros. Ultimate
Sir if the substance has only one colour then is it pure or not? Also why does pencil not dissolve thx
If it only has one colour after chromatography then it is pure. Pencil does not dissolve because it is made of graphite which is a giant covalent molecule and is insoluble in water.
WHAT CAN U SAY ABOUT THE SUBSTANCES BASED ON THE DISTANCE THEY TRAVEL UP THE SOLVENT?
If they move less, then they have a strong attraction to the paper. vice versa
In this example since the unknown substance splits into substances that line up with A, C and D we can work out that the unknown substance contains A, C and D
If they are better at dissolving in solvent or not
Time wise, how long would you leave the paper in the beaker before analysing the result?
You leave it until the solvent is almost but not quite at the top. Usually 30 minutes is enough.
Thank you.
Night before paper 2, 2019 yay
I don't get it. Isn't the same stuff covered in C2? Why do we need to learn this again
It's covered in two parts of the spec.
What does it mean by unit?
For example cm, kg etc. The Rf value does not have a unit.
@@Freesciencelessons Thank you!
How to calculate the Rf value of the unknown substance U?
divide the distance the spot is away from the pencil line by the distance the water went from the pencil line
Is there just two practicals for paper 2 ??
there are 4: Practical 5,6,7,8
thank u bestie
Is this for higher
good luck for tomorrow
Thank you soo much
do we need to memorise the Rf formula
Jamie Wardle what is the rf formula?
@@georgeosborn421 distance travelled by compound/distance travelled by solvent
ur da bomb!!!
CHEMISTRY GANG
HE DIDN'T SMILE AT THE END!!!!!
!!!!!!
Day before the exam loll
Why do we leave the solvent to travel up to 3/4 of the chromatography paper?
Because the solvent must not reach the top of the paper otherwise we would not be able to calculate the Rf value (as the solvent has ran off).
@@Freesciencelessons I dont get this. if we remove the chromatography paper when the solvent is around 3/4 up the paper, wouldnt it affect our Rf value. Because if we wont always be dividing the distance travelled by the substance by the same value, (if we can decide when we stop the experiment), wouldnt the Rf value change?
so say we remove the paper when the solvent has travelled 10cm, and repeat the another group removed the paper after the solvent has travelled 15cm, wouldnt the Rf value be different.
nice one sir
top guy
very interesting
Argggg I hate chromatography with a passion not even our hero could save me should I be concerned 😫
you are 𝙩𝙝𝙚 bossman
last min revision anyone?
Exam tommorow...
January exams anyone??
lol whos here in lockdown 3
mock gang wya
a level biology hehe👁👅👁
can he just do my science homework? i don’t feel like it.
Dr Donnelly doesn't do homework, he assigns it.
Nice work!! ^^
Do u have to know about gas chromatography
Kamran Ashraf you just need to know that it is a qualititative analyses
What
saving my ass
good luck today guys :)
Come on lad get in there
Leckie Gang exam in 5 hours🤣
gracias ñery
Last minute squad?
I’m a bit late but yeah
Right who else had got 7 hours till there exam lmao
2026 GCSE anyone?
So peng