1. Chemical Reactions and Equations
Simple Concept: Jab substances milkar naye properties wala substance banate hain.
Types of Reactions:
Combination: Do milkar ek banaye ($A + B \rightarrow AB$).
Decomposition: Ek toot kar do banaye ($AB \rightarrow A + B$).
Displacement: Zyada reactive element kam reactive ko hata de ($A + BC \rightarrow AC + B$).
Double Displacement: Ions ka exchange hona.
Redox: Oxidation (Oxygen judna) aur Reduction (Oxygen hatna) ka saath hona.
Key Effects: Corrosion (Jung lagna) aur Rancidty (Khane ka kharab hona).
2. Acids, Bases and Salts
Acids: Swad mein khatte, Blue litmus ko Red karte hain. $H^+$ ions dete hain.
Bases: Swad mein kadve, Red litmus ko Blue karte hain. $OH^-$ ions dete hain.
pH Scale: 0 se 14 tak. 7 Neutral hai, 7 se kam Acid, aur 7 se zyada Base.
Important Salts:
Baking Soda: $NaHCO_3$ (Cooking mein use).
Washing Soda: $Na_2CO_3 \cdot 10H_2O$ (Safai mein use).
Plaster of Paris (POP): $CaSO_4 \cdot \frac{1}{2}H_2O$ (Haddi jodne mein use).
3. Metals and Non-Metals
Physical Properties: Metals chamakdar aur solid hote hain; Non-metals nahi.
Chemical Properties: Metals basic oxides banate hain, Non-metals acidic.
Reactivity Series: K > Na > Ca... Gold (Au) sabse kam reactive hai.
Ionic Compounds: Metals aur Non-metals ke beech electrons ke transfer se bante hain (High melting point).
Metallurgy: Ore se shuddh metal nikalne ki prakriya.
4. Carbon and its Compounds
Covalent Bond: Electrons ki sharing se banna. Carbon hamesha 4 bonds banata hai (Tetravalency).
Allotropes: Diamond, Graphite, aur Fullerenes.
Hydrocarbons:
Alkanes: Single bond ($C_nH_{2n+2}$).
Alkenes: Double bond ($C_nH_{2n}$).
Alkynes: Triple bond ($C_nH_{2n-2}$).
Functional Groups: Alcohol (-OH), Aldehyde (-CHO), Carboxylic Acid (-COOH).
Saponification: Sabun (Soap) banane ki vidhi.
5. Periodic Classification of Elements
Dobereiner’s Triads & Newlands’ Law of Octaves: Purane classification ke tarike.
Mendeleev’s Periodic Table: Atomic mass par aadharit.
Modern Periodic Table (Henry Moseley): Atomic Number par aadharit.
Groups: 18 Vertical columns.
Periods: 7 Horizontal rows.
Trends: Left to Right jane par Metallic character kam hota hai aur Valency pehle badhti hai phir ghat-ti hai.