Edexcel CHEMISTRY DOUBTS!!!!

[Amelia]

From an Infrared spectrum  how to deduce where the intensity of a peak is broad,weak, medium,strong, varibale and sharp?
Can any one label it on a spectrum to make it clear?

see if these help - http://www.knockhardy.org.uk/sci_htm_files/ir2.pdf
                         http://www.chemguide.co.uk/analysis/ir/interpret.html

[**RoRo**]

How do you balance the following redox equation? :/

MnO₄^- + Fe²⁺ -----> Mn²⁺ + Fe³⁺

[elemis]

How do you balance the following redox equation? :/

MnO₄^- + Fe²⁺ -----> Mn²⁺ + Fe³⁺

Are you sure the equation is correct ?

[Amelia]

I think its something like this :

1. Write the half reactions:

Fe2+(aq)  Fe3+(aq) (oxidation)

MnO4-(aq)  Mn2+(aq) (reduction)

2. Balance each half reaction:

Fe2+(aq)  Fe3+(aq) + e-

MnO4-(aq) + 8H+(aq) + 5e-  Mn2+(aq) + 4H2O

3. Combine the half reactions to give the overall reaction:
5Fe2+(aq)----->  5Fe3+(aq) + 5e- MnO4-(aq) + 8H+(aq) + 5e---->  Mn2+(aq) + 4H2O

 5Fe2+(aq) + MnO4-(aq) + 8H+(aq)  5Fe3+(aq) + Mn2+(aq) + 4H2O

[**RoRo**]

I think its something like this :

1. Write the half reactions:

Fe2+(aq)  Fe3+(aq) (oxidation)

MnO4-(aq)  Mn2+(aq) (reduction)

2. Balance each half reaction:

Fe2+(aq)  Fe3+(aq) + e-

MnO4-(aq) + 8H+(aq) + 5e-  Mn2+(aq) + 4H2O

3. Combine the half reactions to give the overall reaction:
5Fe2+(aq)----->  5Fe3+(aq) + 5e- MnO4-(aq) + 8H+(aq) + 5e---->  Mn2+(aq) + 4H2O

 5Fe2+(aq) + MnO4-(aq) + 8H+(aq)  5Fe3+(aq) + Mn2+(aq) + 4H2O

Thanks Amelia!

[The Golden Girl =D]

secret : look at the atoms

ex:how many Fe are in both sides and balance it and

then the Oxygens ; by adding water molecules.

then the hydrogens ; by adding H + molecules *we're assuming it's in an acidic solution*

and then the electrons ; by adding electrons -gain -> reduction.

It's confusing but u'll get the hang of it with practice =]

[Amelia]

Thanks Amelia!

You are welcome.

GG's tips are gonna help.

[**RoRo**]

secret : look at the atoms

ex:how many Fe are in both sides and balance it and

then the Oxygens ; by adding water molecules.

then the hydrogens ; by adding H + molecules *we're assuming it's in an acidic solution*

and then the electrons ; by adding electrons -gain -> reduction.

It's confusing but u'll get the hang of it with practice =]

Alright, I'll try getting more equations and work on them, thank you!!

[The Golden Girl =D]

Your most welcome *welcomo *

[**RoRo**]

Guys, I want to ask if anyone has got answers for the Review Questions in the AS Chemistry textbook [Edexcel Chemistry for AS by Graham Hill and Andrew Hunt]? There's a CD that came with the textbook and it only has answers for the 'Test Yourself' questions but not the 'Review Questions', so I was wondering if anyone could be having answers to them, if yes, please let me know!!

[EMO123]

secret : look at the atoms

ex:how many Fe are in both sides and balance it and

then the Oxygens ; by adding water molecules.

then the hydrogens ; by adding H + molecules *we're assuming it's in an acidic solution*

and then the electrons ; by adding electrons -gain -> reduction.

It's confusing but u'll get the hang of it with practice =]

thanx this is also helpfull for my as levels thanxx GG

[The Golden Girl =D]

Your Welcome

[xim7007]

How do you identify different proton environments, when a displayed structure of a compound is given. For example propan-1-ol

[Amelia]

How do you identify different proton environments, when a displayed structure of a compound is given. For example propan-1-ol

Propan-1-ol - CH₃-CH₂-CH₂-OH
There are four different proton environments.
3H's in CH₃ environment.
1H in OH environment.
2H's in each CH₂

While using the Low NMR spectra.
When studying low-resolution proton NMR there are two things to look out for:
• The number of peaks, which gives the number of different proton environments.
• The area under each peak, which gives an idea of the number of protons (hydrogens) in each environment.

[xim7007]

Thanx a lot Amelia...How do we know whether a particular group of hydrogen is a different proton environment?