| name | lab-practical |
| description | Science practical exam prep — experiments list, viva questions, lab record format. The practical component is part of the 20 IA marks. |
Lab Practical & Viva Prep
Experiment List (CBSE 2026-27)
Chemistry Experiments
1. pH determination: HCl, NaOH, ethanoic acid, lemon juice, water, NaHCO₃
VIVA: What is universal indicator? Why is pH of NaOH >7?
2. Properties of acids/bases: reactions with litmus, zinc, Na₂CO₃
VIVA: What gas evolves when acid reacts with metal? (H₂)
3. Reaction types observation:
a) Combination: CaO + H₂O → Ca(OH)₂ (exothermic)
b) Decomposition: FeSO₄ heating → Fe₂O₃ + SO₂ + SO₃
c) Displacement: Fe nail in CuSO₄ → FeSO₄ + Cu
d) Double displacement: Na₂SO₄ + BaCl₂ → BaSO₄↓ + NaCl
VIVA: How do you identify a displacement reaction?
4. Reactivity series: Zn, Fe, Cu, Al with salt solutions
VIVA: Why doesn't Cu displace Zn from ZnSO₄? (Cu is less reactive)
5. Acetic acid properties: odour, solubility, litmus, NaHCO₃ reaction
VIVA: What is the IUPAC name of acetic acid? (ethanoic acid)
6. Soap in hard vs soft water
VIVA: Why doesn't soap lather in hard water? (Ca²⁺/Mg²⁺ ions)
Physics Experiments
7. Ohm's law: V-I graph, determine resistance
VIVA: What is the slope of V-I graph? (resistance)
VIVA: Why do we use rheostat? (to vary current)
8. Series and parallel resistance: find equivalent R
VIVA: In which combination is total R less than individual R? (parallel)
9. Glass slab refraction: measure angles i, r, e
VIVA: Why is emergent ray parallel to incident ray?
10. Glass prism: trace light path, observe dispersion
VIVA: What is the order of colors in spectrum? (VIBGYOR)
11. Convex lens: image for different object distances, find f
VIVA: At what position is image same size as object? (at 2F)
Biology Experiments
12. Stomata: leaf peel mount, observe under microscope
VIVA: What is the function of guard cells? (regulate stomatal opening)
13. CO₂ in respiration: KOH experiment with germinating seeds
VIVA: Why do we use KOH? (absorbs CO₂, creates vacuum)
14. Binary fission (Amoeba) and budding (yeast): prepared slides
VIVA: Is binary fission sexual or asexual? (asexual)
15. Dicot seed: identify embryo parts (radicle, plumule, cotyledon)
VIVA: What develops into root? (radicle) Into shoot? (plumule)
Lab Record Format
For each experiment:
AIM: State clearly in one line
MATERIALS: List all apparatus and chemicals
PROCEDURE: Numbered steps
OBSERVATION: Table format (what you saw)
RESULT/CONCLUSION: One clear statement
PRECAUTIONS: 2-3 bullet points
✅ Use ruled pages, neat handwriting
✅ Draw diagrams of setup with labels
✅ Complete on the SAME DAY as the experiment
