Chemistry: Post your doubts here!

[Awesome12]

princess Anu:

If by any chance you don't get what I have just wrote, then here is a simpler explanation

As we go down the group, the size of the atoms increases right? Thus the outer valence electron goes farther away from the nucleus (the nucleus is at the center). Metallic bonding involves the attraction between the valence of electrons and the nucleus. Since the valence electrons are farther away, there will be less attraction between the nucleus and the electrons. Kinda like a magnet and a strip of iron. The farther you take the strip from the magnet, the weaker the attraction. Since the attraction is weaker, less energy is required to overcome the forces of attraction.

 

[MarcoReus]

So, you people did start studying A Levels in the holidays. :v

 

[Awesome12]

So, you people did start studying A Levels in the holidays. :v

No we didn't. It was just an O level concept.

 

[umer salman]

can any one help me i want chemistry alevel cie papers , all for them combined <latest pastpapers> mcqs,theory and practical

 

[MarcoReus]

How many years?

 

[muhammadali233]

How many years?

ap ka kya haal hai?

 

[MarcoReus]

Fit. Agye humare exclusive past paper compiler.

 

[muhammadali233]

Fit. Agye humare exclusive past paper compiler.

Haan chalein me kuch hoon,ap ka plan tu fail ho gya,khair choren purni baton ko,parhai kaisi ho rahi hai?

 

[umer salman]

at-least 5 years

 

[umer salman]

How many years?

around 5 years .plus it would be good if u get me the physics ones too
but thank u for replying

 

[Uchiha-Sasuke]

The structure already shows CH3 and H.
You need to complete it using the following:
H2N
HO2C
H
OH

kasmay? XD

princess Anu:

If by any chance you don't get what I have just wrote, then here is a simpler explanation

As we go down the group, the size of the atoms increases right? Thus the outer valence electron goes farther away from the nucleus (the nucleus is at the center). Metallic bonding involves the attraction between the valence of electrons and the nucleus. Since the valence electrons are farther away, there will be less attraction between the nucleus and the electrons. Kinda like a magnet and a strip of iron. The farther you take the strip from the magnet, the weaker the attraction. Since the attraction is weaker, less energy is required to overcome the forces of attraction.

adding to what he said ^ atomic size decreases left to right in the peri table (that's why group 1 elements have bigger sized atoms comparatively)

 

[MarcoReus]

kasmay? XD

adding to what he said ^ atomic size decreases left to right in the peri table (that's why group 1 elements have bigger sized atoms comparatively)

Your avatar is awesome. So much win!

I so loved how he put Kakashi through 3 days of illusioned pain and then said "Only 71 hours, 59 minutes and 59 seconds to go".

 

[Uchiha-Sasuke]

Your avatar is awesome. So much win!

I so loved how he put Kakashi through 3 days of illusioned pain and then said "Only 71 hours, 59 minutes and 59 seconds to go".

<----bruv it's sasugay not itachi

 

[MarcoReus]

Sorry. I meant signature. :/

I thought I edited that - probably didn't process or something.

 

[ismaiiil]

Help,
are the bonds in MnO4- dative covalent bonds or simply covalent bonds???
if ever you've got the structure give a link please...

 

[ismaiiil]

Why does CN- have a strong electrical field but I- a weak electrical field, such that CN- causes the d orbitals to split more than the I-???

 

[ShreeyaBeatz]

In chemistry do we have to learn the reaction of ethene being converted to epoxyethane in presence of oxygen?
http://www.chemguide.co.uk/organicprops/alkenes/epoxyethane.html

Havent seen this rxn in my copy yet!

 

[Lucy Black]

hey...can somebody help me out with dis...
its urgent...

 

[♣♠ Magnanimous ♣♠]

hey...can somebody help me out with dis...
its urgent...

7a i) General formula : CnH(2n+1) OH
Now for verifying it that this formula is correct or not let's take example ---> Ethanol which is two carbon alcohol so now put it into formula --> C2H([2*2]+1)OH ===> C2H5OH which means it is correct

ii) To find it's molecular formula we have to calculate emplerical formula mass --> CH3OH --> 12+3+16+1 => 32
Now, mass of 1 mole/emperical formula mass ====> 116/32 ---> 3.625 which is equal to 4
now multiply this number with emperical formula --> 4(CH3OH) ==> C4H7OH

Can you check this second one answer I am not sure fully

 

[♣♠ Magnanimous ♣♠]

Help,
are the bonds in MnO4- dative covalent bonds or simply covalent bonds???
if ever you've got the structure give a link please...

It has Dative bond