In short: Bihar Board Class 10 Science practical exam carries 20 marks (separate from the 100-mark theory paper). The practical is conducted internally by your school and includes one experiment from Physics or Chemistry (8 marks), one activity from Biology (5 marks), a viva voce (4 marks), and a practical record/notebook (3 marks). Most students score 15-18 out of 20 with basic preparation.
The Bihar Board Science practical exam is often overlooked by students who focus entirely on the theory paper. This is a mistake. The practical carries 20 easy marks that can significantly boost your overall Science score. While the theory paper requires deep study, the practical exam rewards basic experimental skills and proper documentation.
Bihar Board Science Practical — Marking Scheme
| Component | Marks | What Is Tested |
|---|---|---|
| Experiment (Physics or Chemistry) | 8 | Perform one experiment, record observations, calculate result |
| Activity (Biology) | 5 | Perform one activity, draw/label diagram, record observations |
| Viva Voce | 4 | Oral questions from the examiner based on your experiments |
| Practical Record / Notebook | 3 | Completeness, neatness, and regularity of your lab notebook |
| Total | 20 | Conducted by school, marks sent to BSEB |
When Is the Practical Exam Held?
The practical exam is typically conducted in January, about 4-6 weeks before the theory exam in February-March. Your school sets the exact date. BSEB provides guidelines, but the school's Science teachers act as internal examiners.
Who Evaluates the Practical?
Unlike the theory paper (evaluated by external BSEB evaluators), the practical is evaluated by:
- Your school's Science teachers (internal examiner)
- Sometimes an external examiner from a nearby school (depends on BSEB guidelines for that year)
- The practical marks are sent directly to BSEB by your school
Physics Experiments — Full List
These are the experiments prescribed by BSEB for Class 10 Science practical. Your examiner will ask you to perform one of these during the exam.
Experiment 1: Finding the Focal Length of a Concave Mirror
Procedure: Use a distant object (tree or building visible through the window). Hold the concave mirror facing the object. Place a white screen in front of the mirror. Move the screen until a sharp, inverted image forms. Measure the distance between the mirror and the screen.
| Observation | Value |
|---|---|
| Object | Distant (at infinity) |
| Image position (screen distance from mirror) | This equals the focal length |
| Nature of image | Real, inverted, diminished |
Key formula: For distant objects, image forms at the focus. So screen distance = focal length (f).
Common mistake: Measuring from the wrong surface of the mirror. Measure from the reflecting surface.
Experiment 2: Finding the Focal Length of a Convex Lens
Procedure: Similar to the concave mirror experiment. Use a convex lens instead. Place it on a stand. Move the screen until a sharp image of a distant object appears.
| Observation | Value |
|---|---|
| Lens type | Convex (converging) |
| Object | Distant (at infinity) |
| Image on screen | Real, inverted, diminished |
| Screen distance from lens | = Focal length |
Key formula: For distant objects, image forms at f. Focal length = distance between lens and screen.
Experiment 3: Verifying Ohm's Law
Procedure: Set up a circuit with a battery, ammeter (in series), voltmeter (in parallel across the resistor), a rheostat, and a known resistance wire. Vary the voltage using the rheostat. Record current (I) and voltage (V) for 5-6 readings.
| S.No. | Voltage V (volts) | Current I (amperes) | V/I (ohms) |
|---|---|---|---|
| 1 | — | — | — |
| 2 | — | — | — |
| 3 | — | — | — |
| 4 | — | — | — |
| 5 | — | — | — |
Expected result: V/I should be approximately constant for all readings. This constant = Resistance (R).
Graph: Plot V vs I. A straight line through the origin confirms Ohm's Law (V = IR).
Common mistake: Connecting ammeter in parallel or voltmeter in series. Remember — ammeter always in series, voltmeter always in parallel.
Experiment 4: Finding the Equivalent Resistance of Resistors in Series and Parallel
Series connection: Connect two known resistors in series. Measure total resistance using ammeter-voltmeter method.
- Expected: R_total = R₁ + R₂
Parallel connection: Connect the same two resistors in parallel. Measure total resistance.
- Expected: 1/R_total = 1/R₁ + 1/R₂
| Connection | R₁ (Ω) | R₂ (Ω) | Expected R_total | Measured R_total |
|---|---|---|---|---|
| Series | — | — | R₁ + R₂ | — |
| Parallel | — | — | R₁R₂/(R₁+R₂) | — |
Experiment 5: Tracing the Path of a Light Ray Through a Glass Slab
Procedure: Place a glass slab on white paper. Trace its outline. Fix two pins on one side. Look from the other side and fix two more pins aligned with the images of the first two. Remove the slab and join the pin positions to trace the refracted ray.
Observations to record:
- Angle of incidence (i)
- Angle of refraction (r)
- Angle of emergence (e)
- Lateral displacement (d)
Key result: The emergent ray is parallel to the incident ray but laterally displaced. Angle of incidence ≈ Angle of emergence.
Chemistry Experiments — Full List
Experiment 1: Identifying Acidic, Basic, and Neutral Solutions Using Indicators
Procedure: Test given solutions with litmus paper (red and blue), phenolphthalein, and methyl orange.
| Solution | Red Litmus | Blue Litmus | Phenolphthalein | Methyl Orange | Nature |
|---|---|---|---|---|---|
| HCl | No change | Turns red | Colorless | Red/Pink | Acidic |
| NaOH | Turns blue | No change | Pink | Yellow | Basic |
| NaCl | No change | No change | Colorless | Orange | Neutral |
| Vinegar | No change | Turns red | Colorless | Red/Pink | Acidic |
| Baking soda | Turns blue | No change | Pink | Yellow | Basic |
Experiment 2: Observing the Reaction of Zinc with Dilute Sulphuric Acid
Procedure: Take zinc granules in a test tube. Add dilute H₂SO₄. Observe gas evolution. Bring a burning matchstick near the mouth of the test tube.
Observations:
- Brisk effervescence (bubbles) observed
- Gas produced burns with a pop sound (hydrogen gas)
- Zinc dissolves
- Reaction: Zn + H₂SO₄ → ZnSO₄ + H₂↑
Experiment 3: Performing and Observing Types of Chemical Reactions
Test for different reaction types:
| Reaction Type | Example | Observation |
|---|---|---|
| Combination | Burning magnesium ribbon in air | Bright white flame, white ash (MgO) |
| Decomposition | Heating ferrous sulphate crystals | Green to white/brown, smell of gas |
| Displacement | Iron nail in CuSO₄ solution | Blue solution turns green, brown deposit on nail |
| Double displacement | BaCl₂ + Na₂SO₄ | White precipitate (BaSO₄) forms |
Experiment 4: Testing the pH of Various Solutions
Procedure: Use pH paper strips. Dip in each solution. Compare the color with the pH chart.
| Solution | Expected pH | Nature |
|---|---|---|
| Lemon juice | 2-3 | Strongly acidic |
| Vinegar | 3-4 | Acidic |
| Water | 7 | Neutral |
| Baking soda solution | 8-9 | Mildly basic |
| NaOH solution | 12-14 | Strongly basic |
Bihar Board Science Padhaao पर Practice करें
AI Tutor — 10 Learning Modes · Quiz, Flashcards, Exam Practice · रोज़ 3 Free Chapters
Biology Activities — Full List
Activity 1: Preparing a Temporary Mount of a Leaf Peel to Show Stomata
Procedure: Peel the lower epidermis of a leaf (Rhoeo or Tradescantia works well). Place it on a glass slide. Add a drop of safranin stain. Place a coverslip. Observe under a microscope.
Diagram to draw: Guard cells surrounding the stomatal pore. Label: guard cell, stomatal pore, epidermal cell, chloroplast.
Viva questions commonly asked:
- What is the function of stomata? (Gas exchange and transpiration)
- Why is the peel taken from the lower surface? (More stomata on lower surface)
- What stain is used? (Safranin)
Activity 2: Observing Binary Fission in Amoeba and Budding in Yeast
Procedure: Observe prepared slides under a microscope. Draw what you see.
Amoeba binary fission diagram: Show the stages — parent cell, nucleus dividing, cytoplasm dividing, two daughter cells.
Yeast budding diagram: Show parent cell with a bud forming, bud growing, bud separating.
Activity 3: Studying the Structure of a Flower (Dissection)
Procedure: Take a complete flower (hibiscus or mustard). Identify and separate the four whorls.
| Whorl | Parts | Function |
|---|---|---|
| Calyx | Sepals (green) | Protect the bud |
| Corolla | Petals (colored) | Attract pollinators |
| Androecium | Stamens (anther + filament) | Male reproductive part (produces pollen) |
| Gynoecium | Pistil (stigma + style + ovary) | Female reproductive part |
Diagram: Draw a labeled diagram of the flower showing all four whorls. Cross-section of ovary is a bonus.
Activity 4: Testing for Starch in a Leaf (Photosynthesis)
Procedure: Take a partially covered leaf (some parts blocked from sunlight for 24+ hours). Boil the leaf in water, then in alcohol (to remove chlorophyll). Wash and add iodine solution. Observe color change.
Result: Parts exposed to sunlight turn blue-black (starch present). Covered parts remain brown (no starch).
Viva Voce — Common Questions and Answers
The viva carries 4 marks. The examiner will ask 4-6 questions based on your experiment and general Science concepts.
Physics Viva Questions
| Question | Answer |
|---|---|
| What is the focal length of a plane mirror? | Infinity |
| State Ohm's Law | V = IR (at constant temperature) |
| What is the unit of resistance? | Ohm (Ω) |
| Why is an ammeter connected in series? | To measure the total current flowing through the circuit |
| What happens to current if resistance is doubled? | Current becomes half (at constant voltage) |
| What is lateral displacement? | The perpendicular distance between the incident and emergent ray in a glass slab |
Chemistry Viva Questions
| Question | Answer |
|---|---|
| What is the pH of pure water? | 7 |
| Name a natural indicator | Litmus (from lichen), turmeric |
| What gas is produced when zinc reacts with HCl? | Hydrogen gas (H₂) |
| What is a displacement reaction? | A more reactive element displaces a less reactive element from its compound |
| Why does the blue CuSO₄ solution turn green with iron? | Iron displaces copper: Fe + CuSO₄ → FeSO₄ (green) + Cu |
| What is the role of a catalyst? | Increases the rate of reaction without being consumed |
Biology Viva Questions
| Question | Answer |
|---|---|
| What is the function of stomata? | Gas exchange (CO₂ in, O₂ out) and transpiration |
| Name the stain used for leaf peel slides | Safranin |
| What is binary fission? | Asexual reproduction where one organism divides into two equal parts |
| What is the male part of a flower called? | Stamen (androecium) |
| Why does iodine turn blue-black with starch? | Iodine forms a complex with starch molecules that absorbs all wavelengths except blue |
| What is the function of the ovary in a flower? | Contains ovules; develops into fruit after fertilization |
How to Score Full Marks in the Practical Exam
Experiment Section (8 marks)
| Action | Marks Impact |
|---|---|
| Perform the experiment correctly | 3-4 marks |
| Record observations neatly in a table | 2 marks |
| Write the correct result/conclusion | 1-2 marks |
| Draw a circuit diagram or ray diagram (if applicable) | 1 mark |
Activity Section (5 marks)
| Action | Marks Impact |
|---|---|
| Perform the activity correctly | 2 marks |
| Draw a labeled diagram | 2 marks |
| Write observation and conclusion | 1 mark |
Practical Record (3 marks)
Your practical notebook should have:
- All experiments and activities completed during the year
- Each entry: date, aim, apparatus, procedure, observation, result
- Neat diagrams with labels
- Teacher's signature on each entry
Tips for the Viva (4 marks)
- Know your experiment thoroughly — the examiner will ask questions related to the experiment you performed
- Know the underlying theory — if you did Ohm's Law, know V=IR, units, and the graph
- Speak clearly and confidently — even if unsure, state what you know
- Do not bluff — if you do not know, say "I am not sure" rather than giving a wrong answer
Day-Before Checklist
- Read through all experiment procedures once
- Review the viva questions listed above
- Check that your practical notebook is complete and signed
- Carry: pencil, eraser, scale, pen, calculator (if allowed)
- Know which experiments your school has covered during the year
- Get a good night's sleep — the practical is performance-based, not memory-based
Frequently Asked Questions
How many marks is the Bihar Board Class 10 Science practical?
The practical exam is 20 marks total: 8 marks for the experiment, 5 marks for the activity, 4 marks for viva voce, and 3 marks for the practical record/notebook. These 20 marks are separate from the 100-mark theory paper.
Is the practical exam conducted by the school or by BSEB?
The practical exam is conducted by your school's Science teachers (internal examiner). BSEB may appoint an external examiner from a nearby school to observe. The marks are submitted by the school to BSEB and added to your final result.
Can I fail in the Science practical exam?
Technically you need 33% (about 7 out of 20) to pass the practical. However, since the practical is internally evaluated and most examiners are your own teachers, failing is uncommon. Students who attend the practical and make a genuine attempt almost always pass.
Do practical marks count in the final Bihar Board result?
Yes. Your final Science score is the sum of theory marks (out of 100) and practical marks (out of 20), with the total normalized appropriately for the marksheet. Practical marks are reported separately on the marksheet.
Which experiment will I get in the exam?
You do not get to choose. The examiner will assign one experiment (Physics or Chemistry) and one activity (Biology) through a chit system or rotation. However, the experiments will always be from the prescribed list, so prepare all of them.
How long is the practical exam?
The practical exam is typically 2-3 hours. This includes time for performing the experiment, the activity, recording observations, and the viva voce. You have sufficient time — do not rush.
Is there a separate practical exam for each Science subject?
No. Bihar Board conducts one combined Science practical that covers Physics, Chemistry, and Biology. You perform one Physics/Chemistry experiment and one Biology activity in the same session.
What if I miss the practical exam?
If you miss the practical due to illness (with medical certificate), most schools arrange a make-up practical exam. If you miss without a valid reason, you may receive zero practical marks, which affects your overall Science score.
Related Guides
Bihar Board Class 10 Vigyan Chapter-Wise Weightage Hindi | Bihar Board Class 10 Ganit Chapter-Wise Weightage Hindi | Bihar Board Class 10 Taiyari Hindi | Bihar Board Class 10 Objective Full Marks MCQ Strategy Hindi | Bihar Board Class 10 Ganit Important Questions Hindi | Bihar Board Class 12 Taiyari Hindi
Practice Bihar Board Science Theory on Padhaao
While the practical is hands-on, the theory behind each experiment matters for the viva and the theory exam. Padhaao covers all Bihar Board Class 10 Science chapters — Physics (Light, Electricity), Chemistry (Acids-Bases, Reactions), and Biology (Life Processes, Reproduction) — with MCQ practice matching the BSEB 50-mark objective pattern.
10 learning modes available. 3 free chapters every day. No download needed.
₹21/महीना (सालाना)
Padhaao पर Bihar Board Science के सभी Chapters
1,044 Chapters सभी Subjects में। 20 lakh+ Students। Pro सिर्फ ₹21/महीना (सालाना)।
Bihar Board Science AI Tutor से Practice करें
आपके Syllabus का हर Chapter। 10 Learning Modes। रोज़ 3 Free।
Science शुरू करें