CTET Paper 2 में Mathematics & Science section के लिए Chemistry के basic concepts, properties, reactions और daily-life applications महत्वपूर्ण हैं। नीचे exam-oriented compact notes दिए गए हैं।
1. Matter
- Matter: जिस पदार्थ का mass हो और space occupy करे।
-
मुख्य अवस्थाएँ:
- Solid
- Liquid
- Gas
- Solid → निश्चित shape और volume
- Liquid → निश्चित volume, लेकिन shape निश्चित नहीं
- Gas → shape और volume दोनों निश्चित नहीं
2. Physical & Chemical Changes
Physical Change
- नया पदार्थ नहीं बनता।
- अक्सर reversible होता है।
- Example: Ice का पिघलना, पानी का जमना।
Chemical Change
- नया पदार्थ बनता है।
- सामान्यतः irreversible होता है।
- Example: Iron का rusting, wood का burning।
3. Elements, Compounds & Mixtures
Element: केवल एक प्रकार के atoms से बना पदार्थ।
Example: Iron, Oxygen, Gold
Compound: दो या अधिक elements का chemical combination।
Example: Water (H₂O), Carbon Dioxide (CO₂)
Mixture: दो या अधिक पदार्थों का physical combination।
Mixture Types
- Homogeneous → Salt solution
- Heterogeneous → Sand + Water
4. Atoms & Molecules
- Atom: Element की सबसे छोटी इकाई जो उसके chemical properties को बनाए रखती है।
- Molecule: दो या अधिक atoms का समूह।
- Proton → Positive (+)
- Electron → Negative (−)
- Neutron → No charge
Important
Atomic Number = Number of Protons
Neutral atom में:
Number of Protons = Number of Electrons
5. Acids, Bases & Salts
Acids
- Generally sour
- Blue litmus → Red
- pH < 7>
- Examples: HCl, H₂SO₄
Bases
- Generally bitter/soapy
- Red litmus → Blue
- pH > 7
- Examples: NaOH, Ca(OH)₂
Neutral
- pH = 7
- Example: Pure Water
Important
Acid + Base → Salt + Water
इसे Neutralization Reaction कहते हैं।
6. pH Scale
| pH | Nature |
|---|---|
| < 7> | Acidic |
| 7 | Neutral |
| > 7 | Basic |
pH value कम → Acidity अधिक
pH value अधिक → Basicity अधिक
7. Metals & Non-Metals
Metals
- Generally shiny
- Good conductors
- Malleable
- Ductile
- Generally hard
Examples: Iron, Copper, Aluminium
Non-Metals
- Generally poor conductors
- Brittle in solid state
- Generally non-lustrous
Examples: Oxygen, Sulphur, Carbon
Important Exceptions
- Graphite conducts electricity.
- Mercury is a liquid metal at room temperature.
8. Chemical Reactions
Chemical reaction में reactants बदलकर new products बनाते हैं।
Common Types
- Combination Reaction
- Decomposition Reaction
- Displacement Reaction
- Double Displacement Reaction
- Oxidation
- Reduction
Example
2H₂ + O₂ → 2H₂O
9. Oxidation & Reduction
Oxidation
- Addition of oxygen
- Removal of hydrogen
- Loss of electrons
Reduction
- Removal of oxygen
- Addition of hydrogen
- Gain of electrons
Oxidation + Reduction = Redox Reaction
10. Rusting
Iron का oxygen और moisture के presence में धीरे-धीरे rust बनाना rusting कहलाता है।
Prevention
- Painting
- Oiling/Greasing
- Galvanization
- Alloying
11. Carbon & Its Compounds
Carbon की valency → 4
Carbon की important properties:
- Tetravalency
- Catenation
Common Compounds
- Methane → CH₄
- Carbon Dioxide → CO₂
- Ethanol → C₂H₅OH
12. Separation of Substances
Important methods:
- Filtration
- Evaporation
- Sedimentation
- Decantation
- Distillation
- Centrifugation
- Chromatography
- Sublimation
Examples
Sand + Water → Filtration
Salt + Water → Evaporation
Different coloured dyes → Chromatography
13. Fuels & Combustion
Combustion
Oxygen के साथ पदार्थ की reaction जिसमें generally heat और light निकलती है, combustion कहलाती है।
Types
- Rapid Combustion
- Slow Combustion
- Spontaneous Combustion
- Explosion
Good Fuel
एक अच्छा fuel:
- High calorific value रखता है
- आसानी से available हो
- कम pollution करे
- आसानी से store और transport हो
14. Everyday Chemistry
Daily life में Chemistry के examples:
- Soap & Detergent
- Baking Soda
- Washing Soda
- Bleaching Powder
- Fertilizers
- Medicines
- Food Preservation
- Cement
- Glass
- Plastics
15. Important Chemistry Facts
| Concept | Important Fact |
|---|---|
| Water | H₂O |
| Carbon Dioxide | CO₂ |
| Oxygen | O₂ |
| Hydrogen | H₂ |
| Common Salt | NaCl |
| Baking Soda | NaHCO₃ |
| Washing Soda | Na₂CO₃·10H₂O |
| Quick Lime | CaO |
| Slaked Lime | Ca(OH)₂ |
| Ammonia | NH₃ |
| Methane | CH₄ |
16. Science & Chemistry Pedagogy ⭐
CTET में Chemistry के साथ Science Pedagogy भी महत्वपूर्ण है।
Important topics:
- Scientific Method
- Observation
- Experimentation
- Inquiry-Based Learning
- Activity-Based Learning
- Discovery Learning
- Problem Solving
- Concept Formation
- Scientific Thinking
- Misconceptions
- Laboratory Activities
- Teaching-Learning Materials
- Assessment
- Remedial Teaching
CTET Key Point
Chemistry को केवल definitions और reactions याद कराने के बजाय experiments, observation और daily-life examples के माध्यम से समझाना अधिक effective teaching approach है।
Quick Revision
Matter → Solid, Liquid, Gas Acid → pH < 7 xss=removed> 7 Acid + Base → Salt + Water Atomic Number = Number of Protons Neutral Atom: Protons = Electrons Oxidation → Loss of Electrons Reduction → Gain of Electrons Carbon Valency = 4 Water = H₂O Common Salt = NaCl Baking Soda = NaHCO₃
Important Chemistry Topics for CTET
Matter → Physical & Chemical Changes → Elements & Compounds → Atoms & Molecules → Acids, Bases & Salts → Metals & Non-Metals → Chemical Reactions → Carbon Compounds → Separation Methods → Combustion → Everyday Chemistry → Science Pedagogy
