Biological, Industrial and Environmental Chemistry
Complete Formula Sheet & Shortcut Bible · BITSAT 2026
CrackIt
Carbohydrates: Structures & Tests
Monosaccharides
Glucose: Aldohexose
Fructose: Ketohexose
Formula: C₆H₁₂O₆
Fructose: Ketohexose
Formula: C₆H₁₂O₆
Glucose and Fructose are functional isomers.
Disaccharides
Formula: C₁₂H₂₂O₁₁
Sucrose → Glucose + Fructose
Lactose → Glucose + Galactose
Maltose → Glucose + Glucose
Sucrose → Glucose + Fructose
Lactose → Glucose + Galactose
Maltose → Glucose + Glucose
Polysaccharides
Formula: (C₆H₁₀O₅)ₙ
Starch: Polymer of α-glucose
Cellulose: Polymer of β-glucose
Starch: Polymer of α-glucose
Cellulose: Polymer of β-glucose
Humans can digest starch but not cellulose.
Reducing Sugars
Have a free hemiacetal group.
All monosaccharides, Lactose, Maltose.
Non-reducing: Sucrose
All monosaccharides, Lactose, Maltose.
Non-reducing: Sucrose
Tollen's Test
Reagent: [Ag(NH₃)₂]⁺
Positive Test: Silver mirror
Tests for aldehydes & reducing sugars.
Positive Test: Silver mirror
Tests for aldehydes & reducing sugars.
Fehling's Test
Reagent: CuSO₄ + Rochelle salt
Positive Test: Red-brown ppt (Cu₂O)
Tests for aliphatic aldehydes.
Positive Test: Red-brown ppt (Cu₂O)
Tests for aliphatic aldehydes.
Proteins & Nucleic Acids
Amino Acids & Zwitterion
Structure: R-CH(NH₂)COOH
At isoelectric point (pI), exists as a dipolar ion (zwitterion) with net charge zero.
At isoelectric point (pI), exists as a dipolar ion (zwitterion) with net charge zero.
Peptide Bond
Amide linkage: -CO-NH-
Formed by condensation reaction between two amino acids with elimination of H₂O.
Formed by condensation reaction between two amino acids with elimination of H₂O.
Nucleic Acid Components
Pentose Sugar + N-Base + Phosphate
DNA: Deoxyribose, A, G, C, T
RNA: Ribose, A, G, C, U
DNA: Deoxyribose, A, G, C, T
RNA: Ribose, A, G, C, U
Base Pairing Rules
Adenine (A) = Thymine (T) (2 H-bonds)
Guanine (G) ≡ Cytosine (C) (3 H-bonds)
In RNA, A pairs with U.
Guanine (G) ≡ Cytosine (C) (3 H-bonds)
In RNA, A pairs with U.
Important Polymers & Monomers
Polyvinyl Chloride (PVC)
Monomer:
Vinyl Chloride
(CH₂=CHCl)
Vinyl Chloride
(CH₂=CHCl)
Teflon (PTFE)
Monomer:
Tetrafluoroethene
(CF₂=CF₂)
Tetrafluoroethene
(CF₂=CF₂)
Nylon 6,6
Monomers:
Hexamethylenediamine
+ Adipic acid
Hexamethylenediamine
+ Adipic acid
Bakelite
Monomers:
Phenol + Formaldehyde
(Thermosetting)
Phenol + Formaldehyde
(Thermosetting)
Natural Rubber
Monomer:
Isoprene
(cis-polyisoprene)
Isoprene
(cis-polyisoprene)
Buna-S
Monomers:
Buta-1,3-diene
+ Styrene
Buta-1,3-diene
+ Styrene
BITSAT Polymer Hacks
Focus on monomers! Most questions ask to identify the monomer of a given polymer.
Remember key classifications: Nylon is a polyamide, Terylene is a polyester, Bakelite is thermosetting.
Biodegradable Polymers are hot topics: PHBV and Nylon 2-Nylon 6 are crucial.
Vulcanization involves heating rubber with sulfur to improve its properties by forming cross-links.
Addition vs. Condensation: Addition polymers have the same empirical formula as their monomer (e.g., polyethene).
Chemistry in Everyday Life
Analgesics (Painkillers)
Non-Narcotic: Aspirin, Paracetamol
Narcotic: Morphine, Codeine
Narcotic: Morphine, Codeine
Aspirin also has anti-blood clotting action.
Antacids
Neutralize stomach acid.
Examples: Mg(OH)₂, Al(OH)₃, Ranitidine, Cimetidine.
Examples: Mg(OH)₂, Al(OH)₃, Ranitidine, Cimetidine.
Antibiotics
Bactericidal (kill): Penicillin
Bacteriostatic (inhibit): Erythromycin, Tetracycline
Bacteriostatic (inhibit): Erythromycin, Tetracycline
Antiseptics vs Disinfectants
Antiseptic: On living tissues (Dettol)
Disinfectant: On non-living objects (Phenol 1%)
Disinfectant: On non-living objects (Phenol 1%)
Artificial Sweeteners
Saccharin: 550x sweeter than sucrose
Aspartame: 100x (unstable at cooking temp)
Alitame: 2000x (high potency)
Aspartame: 100x (unstable at cooking temp)
Alitame: 2000x (high potency)
Environmental Chemistry
Acid Rain
pH of rain water < 5.6
Caused by oxides of Nitrogen (NOₓ) and Sulphur (SOₓ).
Caused by oxides of Nitrogen (NOₓ) and Sulphur (SOₓ).
BOD vs COD
BOD: Biochemical Oxygen Demand
COD: Chemical Oxygen Demand
Higher value = More water pollution
COD: Chemical Oxygen Demand
Higher value = More water pollution
Ozone Layer Depletion
Main cause: Chlorofluorocarbons (CFCs)
Active species: Chlorine free radical (Cl•)
Cl• + O₃ → ClO• + O₂
Active species: Chlorine free radical (Cl•)
Cl• + O₃ → ClO• + O₂
Greenhouse Gases
Major contributors to global warming.
Key gases: CO₂, CH₄, N₂O, CFCs, Water Vapour.
Key gases: CO₂, CH₄, N₂O, CFCs, Water Vapour.
Vitamin Classification
| Property | Fat-Soluble Vitamins | Water-Soluble Vitamins |
|---|---|---|
Vitamins Included | A, D, E, K | B complex, C |
Solubility | Soluble in fats and oils | Soluble in water |
Storage in Body | Stored in liver and adipose tissues | Not stored (regular supply needed) |
Deficiency Example | A: Night blindness, D: Rickets, K: Delayed blood clotting | B₁: Beri-beri, C: Scurvy |