Chemistry: Post your doubts here!

[Thought blocker]

In which species does the underlined atom have an incomplete outer shell?
A - Al2Cl6 (Al underlined)
B - CH3+ (C underlined)
C - Cl2O (O underlined)
D - H2ClC (Cl underlined)
M/J/12(12) Q.4
Answer is B, how?

how many electrons does C have in CH3+ ?

 

[phanttasy]

In which species does the underlined atom have an incomplete outer shell?
A - Al2Cl6 (Al underlined)
B - CH3+ (C underlined)
C - Cl2O (O underlined)
D - H2ClC (Cl underlined)
M/J/12(12) Q.4
Answer is B, how?

 

[Raja2396]

Can anybody help me, if one has these components in Chem 9701 P1 B P2 A P3 B P4 A P5 C, what grade should he expect B or A?

 

[Raja2396]

Hi everyone, AsSalamoAlaikum Wr Wb..

To get things organized in a better way, I am making this thread. As othewise, some queries remain unanswered!

So post your CHEMISTRY doubts in this thread. InshaAllah members around will help you.

Any Chemistry related notes and links will be added here in this post. Feel free to provide the links to your notes around the forum, or any other websites!

Chemistry Notes:


http://www.chemguide.co.uk This is the website, which contains almost everything classified according to the syllabus.

Tips for solving chemistry MCQs 9701/01

Chemistry P5 Tips and Notes

Some links & Notes - by 'destined007'

Chemistry worksheets Link shared by hassam

Chemistry Application Booklet: Mistakes and Corrections!

Calculations for A level Chemistry, author E.N. Ramsden third edition ebook download.


Regards,
XPC Staff.

Can you provide me notes for A2 organic chemistry new syllabus notes? any mind map for organic reactions?

 

[Thought blocker]

Can you provide me notes for A2 organic chemistry new syllabus notes? any mind map for organic reactions?

Check the first link in BLUE below this post in my signature. Check there in chemistry module. ^_^ And do like and vote if u think that notes helped u

 

[Thought blocker]

Can anybody help me, if one has these components in Chem 9701 P1 B P2 A P3 B P4 A P5 C, what grade should he expect B or A?

It depends on what B's and C's u get, if both are higher then u get A if lower then B

 

[Robert Flockhart]

Can someone please with Q.3(b)(i)

 

[kungfuPanda]

Hi guys ,Can anyone tell me Is it permissible for rough work that includes underlining statements of questions ,I do that because it helps me understand questions better,So can we do excessive rough work? I mean its not like excessive excessive just like underlining statements or a simple cut when solving an answer here and there.
is it allowed?

 

[My Name]

Hi guys ,Can anyone tell me Is it permissible for rough work that includes underlining statements of questions ,I do that because it helps me understand questions better,So can we do excessive rough work? I mean its not like excessive excessive just like underlining statements or a simple cut when solving an answer here and there.
is it allowed?

Hey
I do the same.I've never been told that it's a bad thing so it's alright.

 

[sharukh45]

help plz
Hydrogen bonding can occur between molecules of methanol, HCHO, and molecules of liquid Y. What could liquid Y be? A. CH3OH B. CH3CHO, C. CH3COCH3 D. CH3CO2CH3

 

[The Godfather]

https://www.xtremepapers.com/community/threads/skype-a-level-math-tuition-paper-1-2-3-6-7.44001/
Please help me.

 

[ali danish]

can anyone explain why benzene does not undergo nucleophillic addition ????

 

[sharukh45]

HELP PLZZZZZZ
Which physical properties are due to hydrogen bonding between water molecules?
1 Water has a higher boiling point than H2S
2 Ice floats on water
3 The H-O-H bond angle in water is approximately 104

 

[Thought blocker]

can anyone explain why benzene does not undergo nucleophillic addition ????

https://www.quora.com/Why-doesnt-Benzene-undergo-addition-reactions

Hope this makes ur thinking crystal clear

 

[ali danish]

https://www.quora.com/Why-doesnt-Benzene-undergo-addition-reactions

Hope this makes ur thinking crystal clear

yep it helped a lot thanks alot

 

[Thought blocker]

yep it helped a lot thanks alot

Anytime

 

[Saad the Paki]

help plz
Hydrogen bonding can occur between molecules of methanol, HCHO, and molecules of liquid Y. What could liquid Y be? A. CH3OH B. CH3CHO, C. CH3COCH3 D. CH3CO2CH3

Ans is A because hydrogen bonding occurs when hydrogen is bonded to a highly electronegativexperienced atom like N,O,F etc. So only a will fulfill that condition.

HELP PLZZZZZZ
Which physical properties are due to hydrogen bonding between water molecules?
1 Water has a higher boiling point than H2S
2 Ice floats on water
3 The H-O-H bond angle in water is approximately 104

1 and 2 are correct. 3 is wrong.
1 is true as H2O has hydrogen bonding which is stronger than Van der walls forces in H2S so it'll have a higher boiling point.
2 is true as ice forms a widely spaced lattice due to hydrogen bonding making it less dense than water (hence ithe floats).
3 is wrong as bond angles are not related to intermolecular forces.

 

[Thought blocker]

notes on organic synthesis?

 

[ronaldokalaveri]

Chemistry a levels ocr active book anyone?

 

[studentagakhan]

7. Use of the Data Booklet is relevant for this question. In an experiment, the burning of 1.45g (0.025mol) of propanone was used to heat 100g of water. The initial temperature of the water was 20.0°C and the final temperature of the water was 78.0°C. Which experimental value for the enthalpy change of combustion for propanone can be calculated from these results? A –1304kJ mol–1 B –970kJ mol–1 C –352kJ mol–1 D –24.2kJ mol