Chemistry: Post your doubts here!

[shazmina]

http://maxpapers.com/wp-content/uploads/2012/11/9701_w12_qp_41.pdf
Can any1 help me with Question no 1 Part b (vi) .... i dont get from where they are getting 0.045 mol of Cu...
Please help .....

 

[farhan980]

can someone help me with this ? thanks in advance

 

[danial 234]

http://maxpapers.com/wp-content/uploads/2012/11/9701_w12_qp_41.pdf
Can any1 help me with Question no 1 Part b (vi) .... i dont get from where they are getting 0.045 mol of Cu...
Please help .....

moles of Fe3+ in 100 cm3 of partially used solution=0.15-0.06=0.09 moles
As two moles of Fe3+ react with one mole of Cu.
So, 0.09 moles of Fe3+ will react with 0.045 moles of Cu.
Mass of Cu=Moles * Ar

 

[Awesome12]

Why is option 1 only correct?

 

[fantastic girl]

Assalamu Alaikum.
http://www.studentbounty.com/pastpa.../Chemistry (9701)/2010 Nov/9701_w10_qp_43.pdf
Can someone plzz tell me how to do Q2 c :'(
i just did till finding concentration of copper.....i dont get the last step :/ how can mass become the % ? :S

 

[princessnoor]

How to draw structures like these? Nov/14/41

they are very simple look in the marking scheme
In pcl4+ 4 covalent bonds of cl with p and + charge on p
And 6 covalent bonds of p with cl with - charge on p since it had gained electrons

 

[shazmina]

moles of Fe3+ in 100 cm3 of partially used solution=0.15-0.06=0.09 moles
As two moles of Fe3+ react with one mole of Cu.
So, 0.09 moles of Fe3+ will react with 0.045 moles of Cu.
Mass of Cu=Moles * Ar

Thank you soo much Daiyya broh
JazakAllah khairan

 

[NIM]

Guyzz!! How was Chem paper 42???

 

[princessnoor]

Guyzz!! How was Chem paper 42???

A little hard

 

[_Ahmad]

can anyone please explain Q2 (e) of this paper
http://onlineexamhelp.com/wp-content/uploads/2015/02/9701_w14_qp_52.pdf

 

[forever_chocoholic]

what are construction lines?

 

[forever_chocoholic]

can anyone please explain Q2 (e) of this paper
http://onlineexamhelp.com/wp-content/uploads/2015/02/9701_w14_qp_52.pdf

(
( 2x27/( 2x27 + 3x16) ) x 1.50 = 0.794

 

[_Ahmad]

(
( 2x27/( 2x27 + 3x16) ) x 1.50 = 0.794

Can you please elaborate it and explain part (f) too

 

[NIM]

A little hard

2nd last question was kinda tricky!!

 

[Sahan27]

how to find the other element

View attachment 53315

Its Bromine
Cos M+2 peak and M peak are of the same height
if the ratio between the M+2 and the M peak are the same its always Bromine

 

[princessnoor]

2nd last question was kinda tricky!!

The organic one? Yh

 

[Suchal Riaz]

You can try viewing it from the end on the left side. Then visualize them as clock faces, using references with H and CH3 at the 12 o'clock positions.

View attachment 53391

oh that makes it much easier. I had no teacher so i deduced that method of mine myself.

 

[_Ahmad]

can anyone please explain Q2 (e) and (f) of this paper
http://onlineexamhelp.com/wp-content/uploads/2015/02/9701_w14_qp_52.pdf

 

[Ch.Walid]

Here's a great video explaining trends in the periodic table.

Trends in the periodic table

 

[randomcod]

w09 qp 5
If anyone can have a look at it... From what point do we consider it to be 'higher temperature', and from what point do we consider it 'lower temperature'?