NEET · Chemistry · Amines & Biomolecules doubts
9 doubts found
Why does egg white turn solid and opaque when you cook it (or add acid)?
Egg white is mostly protein folded into a precise 3-D shape held by relatively weak bonds (hydrogen bonds, disulfide and ionic links).
Why is aniline a much weaker base than methylamine?
Basicity depends on how available the nitrogen's lone pair is to grab a proton.
How are diazonium salts used to make the bright dyes in clothes?
A primary aromatic amine treated with nitrous acid at low temperature (0–5°C) forms a diazonium salt.
Why does glucose give a positive Fehling's/Tollens' test but table sugar (sucrose) doesn't?
These tests need a free aldehyde (or α-hydroxy ketone) group that can be oxidised.
What does “Basicity of amines” actually mean in Amines & Biomolecules, and why does it matter for NEET?
amines are basic because the nitrogen lone pair can accept a proton; aliphatic amines are more basic than ammonia, aniline is less.
I keep getting “Basicity of amines” questions wrong in Amines & Biomolecules. What's the trap?
thinking aniline is more basic than an alkylamine.
What does “Reducing vs non-reducing sugars” actually mean in Amines & Biomolecules, and why does it matter for NEET?
sugars with a free aldehyde/ketone group (glucose, fructose, maltose) reduce Tollens'/Fehling's; sucrose does not.
I keep getting “Reducing vs non-reducing sugars” questions wrong in Amines & Biomolecules. What's the trap?
assuming every sugar is a reducing sugar.
What is the difference between aliphatic amine and aromatic amine (aniline)?
An aliphatic amine (e.g. methylamine) has a freely available lone pair and is more basic than ammonia; in aniline the lone pair delocalises into the ring, making it a much weaker base.