Valence electrons are the one present in the outer most shell of an atom. Therefore, in case of transition metals the valence electrons are present in the outer shell and that's the 4s and 3d shell. And it won't be adsorption because in adsorption a substance is interacting physically with a solid surface. Whereas here, the substance is chemically interacting with the solid. Thus chemisorption. Hope this helps

The video is in English

I know this reply is very late but I do OCR B Salters aswell and barely any other sixth forms do it - my sixth form is the only one in the area which is so annoying! Also, I hope you did well in your exam!

Yes - pretty much everything is still necessary for the reformed specification.

Make a more expressive one - we'd love to post it for the benefit of all :)

its only AS I guess so maybe you don't need that much detail

No, the water is present in the reaction mixture as liquid water so the state symbol is (l). It doesn't matter that there are other things present too, the state of the water is liquid.

Normally the abundance is given as a percentage scale, so everything should add up to 100 - or something is missing. Check the question carefully to be sure you aren't supposed to assume that the rest is due to some other isotope. If the values really do add up to some arbitrary total, other than 100, then you would just divide by that total.

With all due respect, if you just want to read something I'd suggest you get a book. These videos are here for people who value some extra explanation.

i'm just giving my opinion. it's your wish idk. i was telling that as you talk explain also on paper.

you just got PARRED

@@himanshubhushan3927 Some people learn better by listening, hence why they're watching a video rather than reading straight from the textbook. If you didn't understand this you probably learn differently and shouldn't be using videos, but rather something else.

Hi Trevor, the videos are made for students studying the OCR B A' level Chemistry course. The new specification no longer requires them to know how the mass spectrometer works. In fact I think AQA is the only course left that still includes this. If you're not doing the AQA course, check that your teacher has read the new spec :)

You need to know how to interpret the spectra that mass spec produces, but you don't need to know how the machine works. Look at the current specification if you don't believe me. It used to be in EL before the change to linear A' levels a couple of years ago, but was removed.

C: 55.81/12=4.65 O: 37.17/16=2.32 H: 7.02/1=7.02 Dividing each by the smallest gives... C = 2 O = 1 H = 3 That ratio gives the empirical formula. The molecular formula could be any multiple of the empirical formula; C2H3O or C4H6O2 or C6H9O3 etc. To decide which it is, you would need further information - e.g. the molecular mass or the number of carbons in the molecule etc.

+Ikeoluwa Olagunju From lowest to highest, the order will be B-C-A. 'Substance A' will have the highest boiling point out of the three as it is the longest (6 carbons) and straightest out of the carbon chains shown. This gives the most opportunity for instantaneous dipole - induced dipole intermolecular bonds to form between the molecules of 'substance A'. As a result, more energy will be needed to break the intermolecular bonds between the molecules when 'substance A' moves from the liquid state to gas state than will be required for either substance B or C. B and C both have 4 carbons, but C is a straight chain whereas B is branched. This means molecules of C will pack more closely, allowing stronger instantaneous dipole - induced dipole intermolecular bonds to form between the molecules of 'substance C' (compared to B). As a result, more energy will be needed to break the intermolecular bonds between the molecules when substance C moves from the liquid state to gas state than will be required for substance B.Hope that makes sense.

We've been developing these videos for a few years now, so mostly they have their origin with the old course. However there hasn't been a lot of change with the new course, and we are adding, changing and removing things as we go along to make sure they reflect any differences as far as possible. There are still more to make, but life is busy.

+Chemistry QMC Ok Thanks

+TheStereo941 This was one of my first videos, done before somebody pointed out that going really slowly was unnecessary as it is quite easy to go rewind and watch again if something doesn't make sense! The pace is way too slow - but the content is fine, so I'm leaving it as it is for the moment.

Yup really great 🤠👍