Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012
Chemistry exam discussion - share revision tips in preparation for GCSE, A Level and other chemistry exams and discuss how they went afterwards.
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Re: Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012yh lol...the thing is, sometimes i feel i have learnt a topic but then i get killed by the past papers(Original post by scorpio22)
Haha .Agreed
F321 has finally been learnt and i just need to improve minor areas
F322 is just not happening with me.I know everything individually but i'm not getting my marks on the PPQ
Im supposed to go away for a weekend ,train tickets & outfits sorted.I doubt I'll be leaving my room any time soon.
100 marks :0
over an hour and a half ;(
btw what r u planning to get >
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Re: Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012the thing is...examiners tend to focus on module three for f321 the most
so anything else "doesnt count"....
im gonna have to focus a bit more on that.....
PLUS...they test application of knowledge rather than what you just know....
any one think the exam (f321) is gonna be hard ??
fingers crossed -
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Re: Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012what should we do in case we get some weird structures and asked to find bong angle like in jan 2012 there was find bong angle of H-N-H? and do u think the grade boundaries for june will be higher than this jan paper?(Original post by Man-Utd)
the thing is...examiners tend to focus on module three for f321 the most
so anything else "doesnt count"....
im gonna have to focus a bit more on that.....
PLUS...they test application of knowledge rather than what you just know....
any one think the exam (f321) is gonna be hard ??
fingers crossed -
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Re: Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012I wasted so much time because of that question as it was one of the last ones.(Original post by otrivine)
what should we do in case we get some weird structures and asked to find bong angle like in jan 2012 there was find bong angle of H-N-H? paper?
I got told to look at how many lone pairs and bonding pairs surrounding the central atom and using my previous knowledge of angle to apply it. -
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Re: Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012(Original post by Man-Utd)
yh lol...the thing is, sometimes i feel i have learnt a topic but then i get killed by the past papers
100 marks :0
over an hour and a half ;(
btw what r u planning to get >
I have started with the 2002 PPQ as they are easier lool.
I have built up my technique/knowledge as it's literally the same questions repeated but they get harder over the years.
(you know how you have said to focus on module 3 ...what's that topic as my teacher only talks and gives booklets with everything compacted and assignments we do not use books in lesson)
And I plan on getting an A fingers crossed.I have 8 exams but I am only revising for for 2 x chemistry 2x biology, my 2x business will get revised in my free periods as my sciences just dominate my time lol..you? -
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Re: Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012I'm so scared for this exam, but more so for unit 2...I know next to nothing! :O
Ok, let's start posting questions. I'll start
Sodium reacts with Chlorine, forming Sodium Chloride. Describe the bonding in Na, Cl2 and NaCl. -
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Re: Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012The bonding within Cl2 molecules is covalent and intermolecular forces between Cl2 molecules are Van der Waals forces.(Original post by PrincessMedic)
I'm so scared for this exam, but more so for unit 2...I know next to nothing! :O
Ok, let's start posting questions. I'll start
Sodium reacts with Chlorine, forming Sodium Chloride. Describe the bonding in Na, Cl2 and NaCl.
The bonding in NaCl is ionic due to the electrostatic attraction between the positive Na+ cation and the Cl-anion. -
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Re: Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012im getting from 44-48 can we aSK EACH OTHER questions?(Original post by scorpio22)
what marks/grades is everyone getting in their ppq practice?
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Re: Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012CORRECT!(Original post by Natalie21)
The bonding within Cl2 molecules is covalent and intermolecular forces between Cl2 molecules are Van der Waals forces.
The bonding in NaCl is ionic due to the electrostatic attraction between the positive Na+ cation and the Cl-anion.
Ah, I always fail with the past papers! I learn the topics and think I have them in my knowledge, but once I do a past paper...the knowledge just disappears(Original post by scorpio22)
what marks/grades is everyone getting in their ppq practice?
Ok, next question...describe how van der Waals forces arise. -
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Re: Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012van der waals forces arise due to movement of electrons and unbalances the distribution of charge and an induce dipole forms and instantaneous dipoles forms between molecules and arises to van der waals forces(Original post by PrincessMedic)
CORRECT!
Ah, I always fail with the past papers! I learn the topics and think I have them in my knowledge, but once I do a past paper...the knowledge just disappears
Ok, next question...describe how van der Waals forces arise. -
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Re: Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012CORRECT(Original post by otrivine)
van der waals forces arise due to movement of electrons and unbalances the distribution of charge and an induce dipole forms and instantaneous dipoles forms between molecules and arises to van der waals forces
NEXT QUESTION: State and explain the trend in the boiling points of Chlorine, Bromine and Iodine. (3 marks) -
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Re: Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012as you go down the group the boiling point increases because increase number of electrons and more van der waals forces are present and therefore more energy needed to break the bonds.(Original post by PrincessMedic)
CORRECT
NEXT QUESTION: State and explain the trend in the boiling points of Chlorine, Bromine and Iodine. (3 marks)Last edited by otrivine; 13-04-2012 at 21:59. -
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Re: Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012Right again(Original post by otrivine)
as you go down the group the boiling point increases because more van der waals forces are present and therefore more energy needed to break the bonds.
*NEXT QUESTION:* The properties of Graphite are: Good conductor, soft and high melting point.
a) Describe the bonding and structure in Graphite.
b) Explain, in terms of bonding and stucture, the properties of Graphite listed above.
(5 marks) -
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Re: Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012a) graphite are hexagonal shaped and have weak layers and they are held by covalent bond.(Original post by PrincessMedic)
Right again
*NEXT QUESTION:* The properties of Graphite are: Good conductor, soft and high melting point.
a) Describe the bonding and structure in Graphite.
b) Explain, in terms of bonding and stucture, the properties of Graphite listed above.
(5 marks)
b) high M.P because there are strong convalent bond between molecules and more energy needed to break bonds. Soft because the layers are weak and can slide over each other. Good conductor because the outer electron is delocolised and can move throughout the structure. -
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Re: Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012You have good answers,have you learnt this or your looking at notes?(Original post by otrivine)
a) graphite are hexagonal shaped and have weak layers and they are held by covalent bond.
b) high M.P because there are strong convalent bond between molecules and more energy needed to break bonds. Soft because the layers are weak and can slide over each other. Good conductor because the outer electron is delocolised and can move throughout the structure. -
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Re: Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012haha me too(Original post by PrincessMedic)
Ah, I always fail with the past papers! I learn the topics and think I have them in my knowledge, but once I do a past paper...the knowledge just disappears
I have spent 2 weeks just on chemistry..I know my content i just need to remember them too.I forget all the time.I'm getting 75%
Since i have started revising f322 ,f321 has become so much easier.but the is so much more improve on f322 lool.
I happen to have the whole stage of it contracting on my wall.The joy of sticky notes 
