Chemistry: Post your doubts here!

[Jinosupreme]

Which statements are true for an SN2 reaction?
1 One bond is broken as another bond is formed.
2 The formation of a transition state involves the collision of two molecules or ions.
3 A carbon atom in the transition state is bonded, either fully or partially, to five other atoms.

Answer is 1,2,3. Anyone can explain?

 

[periyasamy]

Guys another question here.Thanks .Ans for this is b.What is meant by the sentence"in which process is a transition element compound used rather than the element itself"

 

[periyasamy]

Which statements are true for an SN2 reaction?
1 One bond is broken as another bond is formed.
2 The formation of a transition state involves the collision of two molecules or ions.
3 A carbon atom in the transition state is bonded, either fully or partially, to five other atoms.

Answer is 1,2,3. Anyone can explain?

Yeah boss should be all 3.The sn 2 mechanism is substitution bimolecular whereby bond break and form at same time.So,unlike sn1 it occur at 1 go as both molecules collide at same time n this also causes the formation of 5 bonds(2 partially bond ,one that is going to break and another that is going to form.Look at the notes of halogenoalkane,it is sure explained better.

 

[snowbrood]

Can someone explain these three questions to me pleaseeee :/

 

[snowbrood]

Can someone explain these three questions to me pleaseeee :/

 

[snowbrood]

Guys another question here.Thanks .Ans for this is b.What is meant by the sentence"in which process is a transition element compound used rather than the element itself"

for A and D we use platinium for C we use Iron but for B we use vanadium oxide rather than vanadium so hope this answers ur question

 

[periyasamy]

u rock man......

 

[periyasamy]

Need more help here.
Thanks a lot guys for always helping.All of u r sure always in my prayers .Lets succeed our goal together.
Ans for question 22 is c.

 

[Isaac CKR]

October/November 2011 (Variant 3), Question 33.
How do I do this question?

 

[periyasamy]

U s

October/November 2011 (Variant 3), Question 33.
How do I do this question?[/quote
Boss,this is like a fact H2so4 act as a reducing agent to both br2 and i2 but not cl2.I think that is what they want.Answer should be option 1 and 2.

 

[snowbrood]

Need more help here.
Thanks a lot guys for always helping.All of u r sure always in my prayers .Lets succeed our goal together.
Ans for question 22 is c.

for q22
a free radical ? well it would be one less hydrogen atom right ?
rule 1 take hydrogen from primary carbon atoms only as the secondary ones are stable very much stable than primary ones
u can take an hydrogen from ethyl group
from 3 methyl groups
so it would be 4 but the answer says 3?
well if u take hydrogen from the methyl at top or bottom it would still be same thing
so there are 3 different forms

 

[periyasamy]

for q22
a free radical ? well it would be one less hydrogen atom right ?
rule 1 take hydrogen from primary carbon atoms only as the secondary ones are stable very much stable than primary ones
u can take an hydrogen from ethyl group
from 3 methyl groups
so it would be 4 but the answer says 3?
well if u take hydrogen from the methyl at top or bottom it would still be same thing
so there are 3 different forms

Thank u.

 

[Isaac CKR]

U s

TYVM

 

[snowbrood]

Thank u.

we dont know the reactions of D will be same as that of H(hydrogen ) as the number of electrons and protons is still the same
so lets consider NH4cl+Cao u do know that it will form
CaO(s) + 2 NH4Cl(s) 2 NH3(g) + H2O(g) + CaCl2(s)
D is no exception here so 1 is correct
for option 2
we know that hydrolysis of cyanide gives an carboxyllic acid and ammonia
here is a base hydrolysis we have same number of D atoms as we would have expected for H atoms

for question 3

NH4+ yields NH3
but we dont have 4D atoms here we have only 1D so it is not possible
since 1 and 2 are correct option B seems the right option
i

 

[periyasamy]

Guys,I dont really get this question.anyone have a clue?

 

[periyasamy]

we dont know the reactions of D will be same as that of H(hydrogen ) as the number of electrons and protons is still the same
so lets consider NH4cl+Cao u do know that it will form
CaO(s) + 2 NH4Cl(s) 2 NH3(g) + H2O(g) + CaCl2(s)
D is no exception here so 1 is correct
for option 2
we know that hydrolysis of cyanide gives an carboxyllic acid and ammonia
here is a base hydrolysis we have same number of D atoms as we would have expected for H atoms

for question 3

NH4+ yields NH3
but we dont have 4D atoms here we have only 1D so it is not possible
since 1 and 2 are correct option B seems the right option
i

Thanks man.

 

[periyasamy]

we dont know the reactions of D will be same as that of H(hydrogen ) as the number of electrons and protons is still the same
so lets consider NH4cl+Cao u do know that it will form
CaO(s) + 2 NH4Cl(s) 2 NH3(g) + H2O(g) + CaCl2(s)
D is no exception here so 1 is correct
for option 2
we know that hydrolysis of cyanide gives an carboxyllic acid and ammonia
here is a base hydrolysis we have same number of D atoms as we would have expected for H atoms
for question 3

NH4+ yields NH3
but we dont have 4D atoms here we have only 1D so it is not possible
since 1 and 2 are correct option B seems the right option
i

Boss,sorry but what do u mean by that here is a base hydrolysis we have same number of D atoms as we would have expected for H atoms.

 

[Isaac CKR]

Need help with this question . Thank you in advance.

 

[periyasamy]

Need help with this questionView attachment 33027 . Thank you in advance.

I got to go out know.But generally what u need to do is this.First form a half equation for for pb ion n bromide ion.U will then get the ratio.So then u find the mole of pb ion using the mass given.Finally with the ration value,u can get the value of bromine.

 

[Jessie N.]

Thank you so much ( *｀ω´)