WJEC AS &amp; A2 Chemistry

Original post by kayla:)

Meeee

Though I can't remember much at all. I need 90% really too....Ugh

Me too! I worked out I need about 102/120 in CH4 if I have any chance of getting the A*.
CH4 is really hard :/

Reply 82

Original post by planetconwy1

Me too! I worked out I need about 102/120 in CH4 if I have any chance of getting the A*.
CH4 is really hard :/

I'm just looking for 108 in both hopefully. Saying that it sounds so hard, but with 120 and 118 second time round in AS I'm hoping it won't be too bad. Revision sucks though :frown:

I don't like how far away the exams are, cos I'm thinking, na don't need to start revising properly now, when really I do :frown:

You doing biol as well?

Reply 83

Original post by kayla:)

I'm just looking for 108 in both hopefully. Saying that it sounds so hard, but with 120 and 118 second time round in AS I'm hoping it won't be too bad. Revision sucks though :frown:

I don't like how far away the exams are, cos I'm thinking, na don't need to start revising properly now, when really I do :frown:

You doing biol as well?

Yeah i did BY4 in January and got 108, which im really pleased with, and ive just finished BY6 yesterday which i felt went really well so hopefully an A*

What about you?

Reply 84

Original post by planetconwy1

Yeah i did BY4 in January and got 108, which im really pleased with, and ive just finished BY6 yesterday which i felt went really well so hopefully an A*

What about you?

I did BY4 in jan and got 120 :colondollar:

so hopefully a* there :P
You don't include practicals in it though, only that you need an A overall, and over 90% in both modules (Y) I've been told anyway

Reply 85

Original post by kayla:)

I did BY4 in jan and got 120 :colondollar:

so hopefully a* there :P
You don't include practicals in it though, only that you need an A overall, and over 90% in both modules (Y) I've been told anyway

No, you do indeed count practicals, you need 108/120 in BY4 and BY5 and 54/60 in BY6. or just 270/300 in the A2 level. And an A in the A-Level overall.

Reply 86

Original post by planetconwy1

No, you do indeed count practicals, you need 108/120 in BY4 and BY5 and 54/60 in BY6. or just 270/300 in the A2 level. And an A in the A-Level overall.

You don't count practicals.... cos last year people in my college got c/d in prac but still got the A*....

*however, on the website it just says units, but my college say it isn't pracs too cos they did have people with c/d last year who got A* so I don't know....

(edited 13 years ago)

Reply 87

Original post by kayla:)

You don't count practicals.... cos last year people in my college got c/d in prac but still got the A*....

*however, on the website it just says units, but my college say it isn't pracs too cos they did have people with c/d last year who got A* so I don't know....

Oh well I think your College must be wrong because I spoke to WJEC about an issue a few weeks ago and the guy on the phone said then that BY6 is included so it must.

Reply 88

Original post by planetconwy1

Oh well I think your College must be wrong because I spoke to WJEC about an issue a few weeks ago and the guy on the phone said then that BY6 is included so it must.

Ugh... That's crappy. I'm okay with Chem, my tutor said I should get about 53ish, but that is subject to change. Not sure in biol though :frown:

Reply 89

Original post by kayla:)

Ugh... That's crappy. I'm okay with Chem, my tutor said I should get about 53ish, but that is subject to change. Not sure in biol though :frown:

Yeah same, I think I did quite badly in the coursework but i'm sure I will get at least enough marks in CH4 to get an A overall.

What is your chemistry teacher like? We have two in school, I dont really learn from them very much. One of my teachers is this scottish woman, and half the time i cant even understand what she is saying! :biggrin:

Reply 90

Original post by planetconwy1

Yeah same, I think I did quite badly in the coursework but i'm sure I will get at least enough marks in CH4 to get an A overall.

What is your chemistry teacher like? We have two in school, I dont really learn from them very much. One of my teachers is this scottish woman, and half the time i cant even understand what she is saying! :biggrin:

He is amazing. At first I hated him, because I didn't like his teaching methods, I like to learn things topic by topic so I can revise them easily, but he teaches everything together, and mixes everything up, so now I've not done much revision, but I'm quite confident with everything. He's strict, and you wouldn't want to get on his bad side, but he pushes you to the best of your ability. Though he won't take any recognition for it. He just wants you to do well :smile:

My favourite teacher by far!

Reply 91

Original post by kayla:)

He is amazing. At first I hated him, because I didn't like his teaching methods, I like to learn things topic by topic so I can revise them easily, but he teaches everything together, and mixes everything up, so now I've not done much revision, but I'm quite confident with everything. He's strict, and you wouldn't want to get on his bad side, but he pushes you to the best of your ability. Though he won't take any recognition for it. He just wants you to do well :smile:

My favourite teacher by far!

He sounds really cool!

You know 2,4-dinitrophenylhydrazine (Bradys Reagent)? Im really confused, does it show a positive result for Aldehydes AND Ketones?

And also is it an Orange or Yellow precipitate? I can never seem to find a definitive answer!

Reply 92

x_Melissa_x

OP

4

Original post by planetconwy1

He sounds really cool!

You know 2,4-dinitrophenylhydrazine (Bradys Reagent)? Im really confused, does it show a positive result for Aldehydes AND Ketones?

And also is it an Orange or Yellow precipitate? I can never seem to find a definitive answer!

Yeah, it shows a positive result for carbonyl groups (so aldehydes and ketones) :smile:

My teacher told us that writing "orange/yellow", "orange" or "yellow" will get you the marks :smile:

(edited 13 years ago)

Reply 93

IMGP6976 (Large).JPG102.5KB

Original post by planetconwy1

He sounds really cool!

You know 2,4-dinitrophenylhydrazine (Bradys Reagent)? Im really confused, does it show a positive result for Aldehydes AND Ketones?

And also is it an Orange or Yellow precipitate? I can never seem to find a definitive answer!

It's a positive test for Carbonyls. The NH2 group on the 24DNPH reacts with Oxygen of the Carbonyl to remove water - condensation reaction to leave water, and a 24DNPH derivative :smile:

Hope that helps :smile:

Reply 94

x_Melissa_x

OP

4

Original post by kayla:)

It's a positive test for Carbonyls. The NH2 group on the 24DNPH reacts with Oxygen of the Carbonyl to remove water - condensation reaction to leave water, and a 24DNPH derivative :smile:

Hope that helps :smile:

Your attached pic has inspired me to get back to the CH4 revision!

Might even upload a pic of my overly-colourful notes later ha! :tongue:

Reply 95

I am revising, I am revising, I am revising.... I'm also on TSR, so this isn't going very well
So I've decided I'm going to write all the identification tests we need to know for CH4 here :smile:

I'm going to attempt the practical stuff tomorrow... or maybe later today.
So right, here I go...

Phenol
+FeCl3
Pale Yellow to Violet

+Br
Pale Yellow to Cloudy (not as good but still)

Aldehydes
Fehlings
+Fehlings A and B in xs
Blue to Red/Brown

Tollens
+AgNO3 and NH3 in xs
____ to Silver Mirror (not sure what the start is, will edit if anyone knows?)

Carbonyls
+2,4 DNPH (Brady's)
Forms a Orange/Yellow(decide which you think?) ppt

Methyl Ketone/Ethanal
Iodoform Test
+Iodine and NaOH
Forms a Yellow ppt (CI3)

Carboxylic Acid
Decarboxylation
+Sodalime with Heat
Effervescence

Aromatic Amine
Azodyes
+NO2- in acid(H+) with temp <10c and Phenol - Yellow dye (Phenol can be substituted for Napthol and Dye is Red, or any other colours you've been taught :smile:

I think this is all, unless anyone can think of anything else?

Reply 96

Sara_No_H!

Original post by x_Melissa_x

Your attached pic has inspired me to get back to the CH4 revision!

Might even upload a pic of my overly-colourful notes later ha! :tongue:

Sounds like a good idea!

How about we all choose a topic each and upload something to share? :smile:

Reply 97

Original post by Sara_No_H!

Sounds like a good idea!

How about we all choose a topic each and upload something to share? :smile:

I like the sound of this - I tried to pos rep but it said 'you must rate another member before you rate this member again'..... ugh useless! :P

For CH4 we have topic wise

Spectroscopy
Aromaticity and Isomerism
Alcohols and Phenol
Carbonyls/Aldehydes and Ketones
Carboxylic Acids and Derivatives
Nitrogen containing compounds
Organic Synthesis and Analysis ( prac work mainly I reckon)

Who's in?

Reply 98

Original post by x_Melissa_x

Yeah, it shows a positive result for carbonyl groups (so aldehydes and ketones) :smile:

My teacher told us that writing "orange/yellow", "orange" or "yellow" will get you the marks :smile:

Original post by kayla:)

It's a positive test for Carbonyls. The NH2 group on the 24DNPH reacts with Oxygen of the Carbonyl to remove water - condensation reaction to leave water, and a 24DNPH derivative :smile:

Hope that helps :smile:

Thanks for the help everyone! Im really getting into the CH4 revision now!

I thought I would upload my own picture, I call it the "Nearly Absolutely Everything You Ever Need To Know About Organic Chemistry" page haha :biggrin:

Reply 99