Biology; Chemistry; Physics: Post your doubts here!

[ZaqZainab]

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what is the answer C or D ?

c

 

[sourov97]

c

why?

 

[TheLeagueofShadows]

View attachment 26553
option A is correct but isn't option D correct too?

Option O is correct, but not D. The formula which is displayed in the question is not a structural formula, rather, it is a displayed formula. The structural formula would have been CH3OH, without any bonds shown between them.

 

[ZaqZainab]

why?

because alkali metals are group 1 so they have low density

 

[ZaqZainab]

View attachment 26559
answer pls!

A is it?

 

[asma tareen]

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answer pls!

A cux i guess its photosynthesis

 

[sourov97]

Option O is correct, but not D. The formula which is displayed in the question is not a structural formula, rather, it is a displayed formula. The structural formula would have been CH3OH, without any bonds shown between them.

the structural formula is given in D...the problem is that it is not the FULL structural formula (OH should be O-H)

 

[TheLeagueofShadows]

the structural formula is given in D...the problem is that it is not the FULL structural formula (OH should be O-H)

As I said, this is NOT the structural formula. The formula displayed here is a DISPLAYED FORMULA.
In a DISPLAYED Formula, we show all atoms AND THE BONDS BETWEEN THEM.
In a STRUCTURAL Formula, we only show the atoms, WITHOUT THE BONDS.

H
l
H--C--OH is a Displayed formula. CH3OH is the structural formula.
l
H

 

[TheLeagueofShadows]

Don't confuse yourself that I put the bonds with H, instead of C. I made the bonds with C but when I posted them, they somehow automatically shifted. Its Carbon which has 4 valencies. And It does not matter if we write OH or O-H, both are the same.

 

[ZaqZainab]

.......H
.......l
H--C--OH is a Displayed formula. CH3OH is the structural formula.
.......l
.......H

 

[sourov97]

As I said, this is NOT the structural formula. The formula displayed here is a DISPLAYED FORMULA.
In a DISPLAYED Formula, we show all atoms AND THE BONDS BETWEEN THEM.
In a STRUCTURAL Formula, we only show the atoms, WITHOUT THE BONDS.

H
l
H--C--OH is a Displayed formula. CH3OH is the structural formula.
l
H

ohhh! that IS the STRUCTURAL FORMULA
never heard of the term DISPLAYED Formula.
but if u still want proof...

the ans is not D! i wrote D for ur definition and got it wrong!

 

[sourov97]

.......H
.......l
H--C--OH is a Displayed formula. CH3OH is the structural formula.
.......l
.......H

god CH3COOH is the molecular formula

 

[TheLeagueofShadows]

the answer will be b in my opinion^.
And why don't you understand?
You basically said yourself that ''the ans is not D''. if you read the q again, it is written: ''it can be predicted from their FORMULA''
The formula displayed is the DISPLAYED FORMULA.

 

[ZaqZainab]

god CH3COOH is the molecular formula

i know i just copied the league of shadows post and edited the formula

 

[ZaqZainab]

the answer will be b in my opinion^.
And why don't you understand?
You basically said yourself that ''the ans is not D''. if you read the q again, it is written: ''it can be predicted from their FORMULA''
The formula displayed is the DISPLAYED FORMULA.

Wait listen is it not THAT display and structure is the same

 

[sourov97]

the answer will be b in my opinion^.
And why don't you understand?
You basically said yourself that ''the ans is not D''. if you read the q again, it is written: ''it can be predicted from their FORMULA''
The formula displayed is the DISPLAYED FORMULA.

according to u both of their structural formula should be same : C4H10....but it is not. Understood?

 

[TheLeagueofShadows]

Yar why are you guys confusing different concepts?
The displayed and the structural formula of an organic compound is same.. BUTTT.. The displayed and the structural formula of isomers of a compound are different.
The q sourov just posted shows two ISOMERS. You can count the carbon and the hydrogen atoms. However, their structure is different as they are arranged differently in their displayed formulaes.

 

[ZaqZainab]

according to u both of their structural formula should be same : C4H10....but it is not. Understood?

nope?

 

[ZaqZainab]

Yar why are you guys confusing different concepts?
The displayed and the structural formula of an organic compound is same.. BUTTT.. The displayed and the structural formula of isomers of a compound are different.
The q sourov just posted shows two ISOMERS. You can count the carbon and the hydrogen atoms. However, their structure is different as they are arranged differently in their displayed formulaes.

this is killing my brain what am i doing here i am an IGCSE student

 

[usama321]

Just copying what the examiner report has to say about that structural formula question

"
In a fully displayed structural formula, all the bonds between the atoms are shown. The bond between the O and the H in option D was missing and the correct answer was
A"
Guess i was right in the start