CHEM P42 GT and paper discussion

[A*(a*)]

when Nh3 was added it acted like a base neutalising the Cl- ions in the solution so the green colour faded and a light blue solution of Cu(h2o)6 was formed. then adding more NH3 precipitated it out Cu(OH)2 and then the Cu(NH3)4(H2O)2 complex forming dark plue solution

but i guess we are not adding water, we are adding nh3. so would it not directly displace the cl ions? forming ppt without formation of cu(h20)6?

 

[Malik777]

what were two reactions in organic chemistry question
one was electrophillic substitution wat was other ??

electrophilic adition

 

[A star]

but i guess we are not adding water, we are adding nh3. so would it not directly displace the cl ions? forming ppt without formation of cu(h20)6?

it clearly said THREE ions THREE colours. and it said NH3(aqueous) so it had water. specificaly mentioning acting as a base meant to provide a clue

 

[A*(a*)]

I wrote this answer,
cl ions are displaced by OH ions in aq NH3 forming (Cu(OH)2(H2O)4)2+ which upon addition of excess ammonia forms dark blue sol (Cu(NH3)4)2+ is responsible for this. displaced Cl ions react with the complex forming green sol (this was really a fluke in the end) (Cu(NH3)4)Cl2.
How much marks out of 5 will I get, pleaseee tell me.

 

[A star]

I wrote this answer,
cl ions are displaced by OH ions in aq NH3 forming (Cu(OH)2(H2O)4)2+ which upon addition of excess ammonia forms dark blue sol (Cu(NH3)4)2+ is responsible for this. displaced Cl ions react with the complex forming green sol (this was really a fluke in the end) (Cu(NH3)4)Cl2.
How much marks out of 5 will I get, pleaseee tell me.

idk prolly 1 for naming the ion but your ans is confusing. no more than 1 cause other than naming one ion partilly corect and that a precipitate forms you have jumbled it up

 

[A*(a*)]

it clearly said THREE ions THREE colours. and it said NH3(aqueous) so it had water. specificaly mentioning acting as a base meant to provide a clue

I even wrote ppt that i forgot to mention in the earlier msg

 

[A*(a*)]

idk prolly 1 for naming the ion but your ans is confusing. no more than 1 cause other than naming one ion partilly corect and that a precipitate forms you have jumbled it up

what's so confusing?

 

[A*(a*)]

I wrote blue ppt -1
then ion responsible for it -1
then blue sol -1
then ion responsible for it -1
Can't I get 4 marks for it? This is what I expected

idk prolly 1 for naming the ion but your ans is confusing. no more than 1 cause other than naming one ion partilly corect and that a precipitate forms you have jumbled it up

 

[A star]

I wrote blue ppt -1
then ion responsible for it -1
then blue sol -1
then ion responsible for it -1
Can't I get 4 marks for it? This is what I expected

thats cause you mixed up the colours

 

[A*(a*)]

thats cause you mixed up the colours

naii yar, I wrote blue ppt for cuoh2 h204 and darkblue for (Cu(NH3)4)2+ . This is what i wrote, is this wrong :O

 

[A star]

naii yar, I wrote blue ppt for cuoh2 h204 and darkblue for (Cu(NH3)4)2+ . This is what i wrote, is this wrong :O

yes its Cu(Oh)2 and Cu(NH3)4(H2o)2

 

[Malik777]

What was the major force holding those chains? :S
I wrote Vander walls in first one & Hydrogen bonding in the second :S
True?

 

[A*(a*)]

yes its Cu(Oh)2 and Cu(NH3)4(H2o)2

jee you can also write Cu(OH)2(H2O)4 instead of CuOH2 I've seen in every ms. Now how much marks should I get?

 

[A star]

jee you can also write Cu(OH)2(H2O)4 instead of CuOH2 I've seen in every ms. Now how much marks should I get?

if yes then may 3 or 4

 

[A*(a*)]

if yes then may 3 or 4

PEACE

 

[itallion stallion]

What was the major force holding those chains? :S
I wrote Vander walls in first one & Hydrogen bonding in the second :S
True?

What if u write covalent in the first part will it be wrong.

 

[A star]

What if u write covalent in the first part will it be wrong.

yes cause covalent bonds are within the chains. you need to tel about inter molecular forces of attraction

 

[Musab100]

What was the major force holding those chains? :S
I wrote Vander walls in first one & Hydrogen bonding in the second :S
True?

yes i also wrote this !! its correct

 

[Musab100]

yes cause covalent bonds are within the chains. you need to tel about inter molecular forces of attraction

vander waal forces are also inter-molecular forces and they always act between non polar compounds like hydrocarbon chains

 

[A star]

vander waal forces are also inter-molecular forces and they always act between non polar compounds like hydrocarbon chains

yesh the answer was vanderwaals and hydrogen/ionic bonding