Chemistry Subject Expert
Specialized knowledge for chemistry studying, problem-solving, and note creation.
Topic Coverage
mindmap
root((Chemistry))
Organic
Functional Groups
Reaction Mechanisms
Nomenclature
Inorganic
Periodic Trends
Coordination Chemistry
Main Group Elements
Physical
Thermodynamics
Kinetics
Equilibrium
Analytical
Titrations
Spectroscopy
Separations
Quick Reference Links
Diagram Patterns
Molecular Structure (ASCII)
H H
\ /
C = C
/ \
H H
(Ethene)
Reaction Mechanism (Mermaid)
flowchart LR
A[Substrate] -->|Nucleophile attacks| B[Transition State]
B -->|Leaving group departs| C[Product]
Electron Configuration
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶
Problem-Solving Patterns
Stoichiometry Problems
- Write balanced equation
- Convert given to moles (using molar mass or molarity)
- Use mole ratio from balanced equation
- Convert to requested units
pH Calculations
| Type | Formula |
|---|
| Strong acid | pH = -log[H⁺] |
| Strong base | pOH = -log[OH⁻], pH = 14 - pOH |
| Weak acid | pH = ½(pKa - log C) |
| Buffer | pH = pKa + log([A⁻]/[HA]) |
Redox Balancing (Acidic Solution)
- Separate into half-reactions
- Balance atoms except O and H
- Balance O with H₂O
- Balance H with H⁺
- Balance charge with e⁻
- Multiply to equalize electrons
- Add half-reactions
Common Notation
| Symbol | Meaning |
|---|
| (aq) | Aqueous solution |
| (s) | Solid |
| (l) | Liquid |
| (g) | Gas |
| ⇌ | Reversible reaction |
| → | Forward reaction |
| Δ | Heat applied |
| ↑ | Gas evolved |
| ↓ | Precipitate formed |
Lewis Structure Steps
- Count total valence electrons
- Draw skeleton structure (central atom)
- Place bonding pairs
- Distribute remaining electrons as lone pairs
- Check octets (or duets for H)
- Form multiple bonds if needed