The Student Room Group

OCR B Salters Chemistry 2014 - F332

Scroll to see replies

Reply 40
For the frequency question the way I remember it; i do this
Eg 367J
Always multiply by a 1000 producing 367000
Then 367000/6.02x10^23
For part b
Get the answer of part a and divide it by 6.63x10^-34
This will always be the question. They won't change it.


Posted from TSR Mobile
What are the main concepts that the advanced notice is based on ? Thanks in advance.
When it talks about 2/5 parts per trillion in corked wine, is it american trillion or uk trillion? (So is 1000 billions a trillion?)
Reply 43
Original post by Sycopation
When it talks about 2/5 parts per trillion in corked wine, is it american trillion or uk trillion? (So is 1000 billions a trillion?)

Yeah that is right it goes up in 1000 so 1000- thousands 1,000,000- million 1,000,000,000- billion 1,000,000,000,000- trillion
Original post by BrokenS0ulz
Energy needed to break one bond of X:

(bond enthalpy (in kJ) x 1000) / Plank's constant

Frequency needed for this:

v=E/h

= answer to last question / Plank's constant

I love these questions they are a free 5 marks :smile:


These questions are so good!! I am dreading if we get asked about skeletal formula eg for isomerism or a bromine reaction dont get that haha
Anyone else retaking from last year?

I got a D in this exam last year, I got an A in the other and should get an A this year, no idea what happened last time! Except the fact that I did zero revision
Original post by Tiam.N
Do we need to know batch vs continuous processes? Or do we get given information on them in the test and ask to evaluate it? Haven't seen it crop up in papers that much.


A question that seems to pop up quite often is why would a firm choose to set up business near to an existing plant.

Can someone please list all the reagents and conditions eg chloroalkane to alcohol is aqueous NaOH under reflux? I know its long but I can't put it all together!!!

Also how are we meant to know the strongest sort of bonds that can form? eg PVC, chloroethane
(edited 9 years ago)
Reply 47
Does anyone know how to answer questions that ask e.g. why is does carbon have a delta positive charge ?
Original post by Mubarak1
Does anyone know how to answer questions that ask e.g. why is does carbon have a delta positive charge ?


Because the atom it is attached to is more electronegative so it pulls the electrons in the bond towards it, making the carbon atom delta +ve and the more electronegative element delta -ve
Original post by Mubarak1
Does anyone know how to answer questions that ask e.g. why is does carbon have a delta positive charge ?


It's related to electronegativity. In a C-Br bond for example, Bromine is more electronegative than Carbon, which means that the electron density shifts towards Bromine, making Bromine partially negative (and thus Carbon is partially positive).
Guys can you give me the types of colour changes and reagents that we need to know in identifying certain products like use of potassium VI dichromate in identifying tertiary alcohol and use of bromine in identification of alkenes.
image.jpg Whats the name of this compound?
Reply 52
Original post by qivo
i don't think we need to know anymore than they both contain hydrogen bonds and that a hydrogen bond is an electrostatic attraction between two partial charges caused by the greater electronegativity of either a nitrogen, oxygen or fluorine compared to a hydrogen. I think the spec just means we need to know they are both examples of hydrogen bonding. But one think that can catch people out is when you draw a hydrogen bond in water that the hydrogen is attracted to one of the lone pairs of electrons around the oxygen and then likewise in similar examples. hope this answers your question


Thanks and I just found in the revision guide that solid ice forms a very open structure and this is due to the oxygen atoms being arranged tetrahedrally with two covalent bonds to hydrogen and two hydrogen bonds to neighbouring water molecules


Posted from TSR Mobile
Original post by Turtlefushsia
image.jpg Whats the name of this compound?


3,7-dimethyloct-3-ene
Reply 54
Original post by BrokenS0ulz
Because the atom it is attached to is more electronegative so it pulls the electrons in the bond towards it, making the carbon atom delta +ve and the more electronegative element delta -ve


Cheers!
Page 1 of this thread contains posts on the reagents etc.
Original post by Totally1337
Guys can you give me the types of colour changes and reagents that we need to know in identifying certain products like use of potassium VI dichromate in identifying tertiary alcohol and use of bromine in identification of alkenes.


Uhm not entirely sure what you mean but for oxidisation of alcohols the colour change is orange to green. And adding bromine to alkenes is brown/orange to colourless.
hey guys I need some help on jan 10 f332 paper question 3aii and 4C for 3aii it is a addition react how ever it says there are 2 different monomers joining together (that's the first thing I don't get) then you have to name it, it is propene from the mark scheme but how did they get that from the co-polymer A confuses me :-/ helppp and for 4C I get phosphoric acid from alkene to alcohol but why is it heat under reflux concentrated and where is the steam???
(edited 9 years ago)
I mean like are there any other reactions that we need to know, where it may ask you to state colour changes.
Original post by chemistrykid123
hey guys I need some help on jan 10 f332 paper question 3aii and 4C for 3aii it is a addition react how ever it says there are 2 different monomers joining together (that's the first thing I don't get) then you have to name it, it is propene from the mark scheme but how did they get that from the co-polymer A confuses me :-/ helppp and for 4C I get phosphoric acid from alkene to alcohol but why is it heat under reflux concentrated and where is the steam???


Co-polymer A is made from butene and propene. When you look at a polymer chain, remember that one monomer will consist of no more than two carbons bonded together - the rest of the chain will be attached as CH3 for example.
So, the first C-C bond is attached to two CH3s, meaning this is butene.
The next C-C bond, however, is attached to 3 hydrogens and only one CH3, so this is propene.
This is why when you draw the repeating units (monomers), you only show one C-C bond, and attach the rest as CH3 for example.
(Tell me if this doesn't make sense)
(edited 9 years ago)

Quick Reply