HS2 Physics Chapter 5 MAGNETISM AND MATTER : Experiments

 

Experiment: Study of a Magnetic Dipole in a Uniform Magnetic Field

Objective:

To study the behavior of a bar magnet (or magnetic needle) placed in a uniform magnetic field and determine the torque and potential energy associated with different orientations.

Apparatus Required:

• Small bar magnet or magnetic needle

• Uniform magnetic field source (Helmholtz coil or Earth’s magnetic field with orientation aid)

• Stand and pivot for suspension

• Protractor or angle measurement setup

• Stopwatch (if oscillations are to be studied)

• Magnetic field measuring device (optional)

Theory:

A magnetic dipole in a magnetic field experiences a torque given by:

$$\vec{\tau} = \vec{m} \times \vec{B}$$

Where:

• $\vec{m}$ is the magnetic moment of the magnet

• $\vec{B}$ is the magnetic field vector

• $\theta$ is the angle between $\vec{m}$ and $\vec{B}$

The potential energy $U$ of the dipole in the field is:

$$U = -\vec{m} \cdot \vec{B} = -mB \cos \theta$$

This implies:

• Minimum energy when $\theta = 0^\circ$ (aligned)

• Maximum energy when $\theta = 180^\circ$ (anti-aligned)

Procedure:

1. Suspend the bar magnet or magnetic needle freely such that it can rotate in a horizontal plane.

2. Align the setup so the needle/magnet is initially in equilibrium (usually pointing along Earth's magnetic field).

3. Apply an external uniform magnetic field using Helmholtz coils or other means.

4. Vary the orientation of the magnet and measure the angle $\theta$ between the magnetic moment and the magnetic field.

5. Record the torque experienced at various angles using the torque formula.

6. Optionally, allow the magnet to oscillate and measure its oscillation period to indirectly estimate magnetic moment.

Observations:

• Angle $\theta$

• Direction of torque

• Calculated torque $\tau = mB \sin \theta$

• Calculated potential energy $U = -mB \cos \theta$

Result:

The torque and potential energy values confirm the theoretical behavior of a magnetic dipole in a uniform magnetic field.

Precautions:

• Ensure the magnetic field is uniform.

• Eliminate external magnetic interferences.

• Ensure accurate angle measurements.

HS2 Physics Chapter 4 MOVING CHARGES AND MAGNETISM : Experiments

 

Experiment: Determination of the Horizontal Component of Earth's Magnetic Field (Bh)

Objective:

To determine the horizontal component of Earth’s magnetic field using a tangent galvanometer.

Apparatus Required:

• Tangent galvanometer

• Ammeter

• Rheostat

• Key

• Battery (or power supply)

• Connecting wires

• A compass box (mounted at the center of the galvanometer)

Theory:

When current passes through the circular coil of the tangent galvanometer, it produces a magnetic field at the center. This field is perpendicular to the plane of the coil. The deflection of the magnetic needle in the compass box at the center is due to the resultant of this magnetic field and the horizontal component of Earth's magnetic field.

Using the tangent law:

$$B = B_h \tan \theta$$

Where:

• $B$ = Magnetic field due to current

• $B_h$ = Horizontal component of Earth's magnetic field

• $\theta$ = Deflection of the needle

Also,

$$B = \frac{\mu_0 n I}{2R}$$

Where:

• $\mu_0$ = Permeability of free space

• $n$ = Number of turns in the coil

• $I$ = Current through the coil

• $R$ = Radius of the coil

From this, we can derive:

$$B_h = \frac{\mu_0 n I}{2R \tan \theta}$$

Procedure:

1. Set up the tangent galvanometer with its plane in the magnetic meridian (i.e., the needle should point in the N-S direction when no current flows).

2. Connect the circuit as per the diagram (battery, key, ammeter, rheostat, and tangent galvanometer in series).

3. Adjust the rheostat to vary the current and note the deflection angle $\theta$ from the compass needle.

4. Record the current from the ammeter for different values of deflection (preferably 30°, 45°, 60°).

5. Calculate $B_h$ using the tangent law.

Precautions:

• The plane of the coil must lie exactly in the magnetic meridian.

• Avoid any nearby magnetic materials.

• Take readings in both directions of current to eliminate errors due to magnetic field asymmetry.

Result:

The horizontal component of Earth’s magnetic field $B_h$ is calculated using the measured deflection angles and current values.

HS2 Physics Chapter 3 Current Electricity: Experiments

 

Experiment 1: Verification of Ohm’s Law

Objective:
To verify Ohm's law by plotting a graph of potential difference (V) versus current (I).

Apparatus:

• Voltmeter

• Ammeter

• Resistor or resistance wire

• Battery or power supply

• Rheostat

• Connecting wires

• Switch

Procedure:

1. Set up the circuit with the resistor, voltmeter in parallel, and ammeter in series.

2. Adjust the rheostat to vary the current through the circuit.

3. For each setting, record the voltmeter and ammeter readings.

4. Repeat for at least 5 values.

5. Plot V vs I on a graph.

Expected Result:
The graph should be a straight line passing through the origin, confirming Ohm’s law.

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Experiment 2: Determination of Internal Resistance of a Cell

Objective:
To determine the internal resistance of a given cell using a potentiometer.

Apparatus:

• Potentiometer

• Cell

• Standard cell

• Galvanometer

• Resistance box

• Key

• Jockey

• Connecting wires

Procedure:

1. Connect the circuit as per the standard potentiometer setup.

2. Measure the potential difference across the cell when no current is drawn (open circuit).

3. Then measure the potential difference when the cell supplies current through a known external resistor.

4. Use the ratio of the potential differences and known resistance to calculate internal resistance using the formula:

$$r = R\left(\frac{V - V'}{V'}\right)$$

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Experiment 3: Measurement of Resistance Using Meter Bridge

Objective:
To determine the unknown resistance using a meter bridge (Wheatstone bridge principle).

Apparatus:

• Meter bridge

• Known resistance box

• Unknown resistor

• Galvanometer

• Jockey

• Battery

• Keys

• Connecting wires

Procedure:

1. Connect the known and unknown resistors on opposite sides of the meter bridge.

2. Connect the galvanometer and jockey as shown in the Wheatstone bridge setup.

3. Slide the jockey to find the null point (zero deflection).

4. Measure the lengths on either side and use:

$$\frac{R_1}{R_2} = \frac{l_1}{l_2}$$

to find the unknown resistance.

HS2 Chemistry unit 5 Coordination Compounds experiments

 

Experiment: Preparation of a Coordination Compound

Aim:
To prepare a sample of the coordination compound potassium tris(oxalato)ferrate(III), K₃[Fe(C₂O₄)₃]·3H₂O.

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Materials Required:

• Ferrous sulfate (FeSO₄·7H₂O)

• Oxalic acid (H₂C₂O₄·2H₂O)

• Potassium oxalate monohydrate (K₂C₂O₄·H₂O)

• Hydrogen peroxide (H₂O₂, 6%)

• Acetone

• Distilled water

• Beakers, glass rods, funnel, filter paper, measuring cylinders, and other standard lab apparatus

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Procedure:

1. Preparation of Iron(III) Oxalate Complex:

   • Dissolve about 5 g of ferrous sulfate in 25 mL of warm distilled water.

   • Add 3 g of oxalic acid to the solution, stir and heat gently. A greenish-yellow precipitate of ferrous oxalate will form.

   • Filter the precipitate and wash it with small amounts of cold water.

2. Formation of Potassium Tris(oxalato)ferrate(III):

   • Transfer the wet ferrous oxalate precipitate into a beaker containing 20 mL of 6% hydrogen peroxide.

   • Stir the mixture gently. The ferrous ion will oxidize to ferric ion, forming a yellow solution of ferric oxalate.

   • Add 2 g of potassium oxalate to the solution while stirring.

   • Heat the mixture slightly (not boiling) to complete the reaction.

3. Crystallization:

   • Cool the solution and add an equal volume of acetone to induce crystallization.

   • Allow the solution to stand undisturbed for 15–20 minutes.

4. Filtration and Drying:

   • Filter the crystals formed using filter paper and a funnel.

   • Wash the crystals with a small amount of acetone.

   • Dry the crystals between filter papers or in a desiccator.

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Observation:

Yellow-green crystals of potassium tris(oxalato)ferrate(III) are obtained.

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Precautions:

• Handle hydrogen peroxide with care; it's a strong oxidizing agent.

• Avoid prolonged heating to prevent decomposition of the complex.

• Use distilled water throughout to avoid contamination.

HS2 Chemistry unit 4 The d- and f Block Elements experiments

 

Experiment Title: Study of Characteristics of d- and f-Block Elements

Objective:

To observe and understand the characteristic properties such as color, oxidation states, complex formation, and magnetic behavior of selected d- and f-block elements.

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Materials Required:

• Solutions of transition metal salts (e.g., FeSO₄, CuSO₄, KMnO₄, Cr₂(SO₄)₃)

• Ammonium hydroxide (NH₄OH)

• Potassium hexacyanoferrate (K₃[Fe(CN)₆])

• Sodium hydroxide (NaOH)

• Hydrochloric acid (HCl)

• Distilled water

• Test tubes

• Dropper

• Glass rod

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Procedure:

A. Color and Precipitate Formation

1. Take about 2 mL of CuSO₄ solution in a test tube.

2. Add a few drops of NH₄OH. Observe the blue precipitate and then deep blue complex formation.

3. Repeat similar steps with FeSO₄ and Cr₂(SO₄)₃, adding NaOH to observe characteristic precipitates.

B. Oxidation States Observation

1. Take KMnO₄ and observe its intense purple color, indicating Mn in +7 oxidation state.

2. Add reducing agent (e.g., FeSO₄) and note the color change to colorless/brown indicating Mn²⁺.

C. Complex Formation

1. Take a few mL of Fe³⁺ solution.

2. Add a few drops of K₃[Fe(CN)₆]. Observe the formation of a deep blue precipitate (Prussian Blue).

D. Magnetic Properties (Demonstration/Observation based)

1. Show different salts (e.g., Cu²⁺, Fe³⁺) near a magnet and discuss their paramagnetic behavior due to unpaired d electrons.

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Observation Table:

Metal Ion	Reagent Added	Color Change / Precipitate	Inference
Cu²⁺	NH₄OH	Blue ppt → Deep blue sol.	Complex formation
Fe²⁺	NaOH	Dirty green ppt	Insoluble hydroxide
Fe³⁺	K₃[Fe(CN)₆]	Deep blue ppt	Formation of complex salt
MnO₄⁻	FeSO₄	Purple to colorless	Redox reaction

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Conclusion:

The d-block elements show variable oxidation states, complex formation, colored ions, and magnetic properties. The f-block elements (lanthanides and actinides) also exhibit similar properties but with a higher tendency for complexation and radioactive behavior (for actinides).

HS2 Chemistry unit 3 Chemical Kinetics experiments

 Based on the attached text from the "Chemical Kinetics" chapter, here's a typical experiment process to determine the rate of a chemical reaction—specifically through the hydrolysis of butyl chloride (C4H9Cl), as detailed in the textbook. This experiment is a standard in chemical kinetics and illustrates how reaction rates are studied.

📘 Experiment: Hydrolysis of Butyl Chloride

Objective:
To determine the rate of hydrolysis of butyl chloride (C₄H₉Cl) in aqueous medium and to calculate the average and instantaneous rate of reaction.

Chemical Equation:
C₄H₉Cl + H₂O → C₄H₉OH + HCl

Materials Required:

• Butyl chloride (C₄H₉Cl)

• Water (distilled)

• Stopwatch

• Titration apparatus (burette, conical flask, pipette)

• Sodium hydroxide (NaOH) solution (for titration)

• Phenolphthalein indicator

• Ice bath or temperature-controlled water bath

• Measuring cylinder or pipette

• Thermometer

Procedure:

1. Preparation:

   • Take a known concentration of butyl chloride and mix it with water in a reaction vessel.

   • Maintain the mixture at a constant temperature (preferably using a water bath).

2. Sampling:

   • At regular time intervals (e.g., every 50 or 100 seconds), withdraw a fixed volume of the reaction mixture.

3. Quenching:

   • Immediately quench the reaction by adding the sample to an ice-cold solution to stop further reaction.

4. Titration:

   • Titrate the withdrawn sample against standard NaOH solution using phenolphthalein as an indicator.

   • This determines the amount of HCl formed, which is stoichiometrically equivalent to the amount of C₄H₉Cl reacted.

5. Calculations:

   • Calculate the concentration of C₄H₉Cl remaining at different time intervals.

   • Determine the average rate of reaction over different intervals using:
     Rate = –Δ[R]/Δt

   • Optionally, plot concentration vs. time graph and draw tangents to find instantaneous rates.

6. Analysis:

   • Use the data to determine order of reaction, rate constant, and confirm if the reaction follows first-order kinetics.

Precautions:

• Maintain constant temperature throughout the experiment.

• Use freshly prepared reagents.

• Carry out titration quickly after quenching to prevent post-quench reaction.

This experiment effectively demonstrates how reaction rates are monitored, and how kinetic parameters are derived from experimental data as discussed in the textbook

HS 1st year : Chemistry chapter 2 experiments

 Experiment Script 1: Identifying Subatomic Particles

Objective: To identify and understand the properties of subatomic particles - protons, neutrons, and electrons.

Materials Required: Model of an atom (3D model or chart), Positive and negative magnets, Balloons, and Sand.

Procedure:

1. Display the model of an atom and explain that it consists of three main subatomic partic...

Experiment Script 2: Thomson’s Model of Atom

Objective: To understand and visualize Thomson’s model of the atom.

Materials Required: Plasticine (clay), Small beads or marbles, A small plastic or glass sphere.

Procedure:

1. Take a small plastic or glass sphere and fill it with plasticine.

2. Insert the beads or marbles representing electrons inside the plasticine, showing that electrons are embedded in a positive charge sphere.

3. Explain the concept using the model.

Observation: The electrons are embedded like seeds in a watermelon.

Conclusion: Thomson’s model suggests that an atom is a positively charged sphere with negatively charged electrons embedded in it.

HS 1st year : Chemistry chapter 1 experiments

 

Experiment: Law of Conservation of Mass

Objective:

To demonstrate the Law of Conservation of Mass, which states that mass cannot be created or destroyed in a chemical reaction.

Materials Required:

• A beaker

• Vinegar (acetic acid)

• Baking soda (sodium bicarbonate)

• A digital weighing balance

• A small balloon

• A conical flask

Procedure:

1. Measure the mass of the empty conical flask using the digital weighing balance.

2. Add a measured amount of vinegar (20 ml) to the conical flask.

3. Measure the mass of the balloon.

4. Add a measured amount of baking soda (5 grams) to the balloon.

5. Carefully stretch the balloon over the mouth of the conical flask without letting the baking soda fall into the vinegar.

6. Weigh the entire setup (flask with vinegar, balloon with baking soda) and record the total mass.

7. Lift the balloon, allowing the baking soda to fall into the vinegar. This will produce carbon dioxide gas, causing the balloon to inflate.

8. After the reaction is complete, weigh the entire setup again.

Observation:

• The mass of the setup (flask, vinegar, baking soda, and balloon) before and after the reaction should remain the same.

Conclusion:

• This experiment demonstrates the Law of Conservation of Mass, as the total mass remains constant before and after the chemical reaction.

HS 1st year Physics Chapter 2: Experiments

 Experiment Title: Study of Motion in a Straight Line

Objective: To study the concepts of displacement, velocity, and acceleration using motion in a straight line.

Materials Required:

• A meter scale

• A stopwatch

• A smooth straight track (or a long straight table)

• A toy car or any other object for motion

• Chalk or markers

• Graph paper

Theory: Motion in a straight line is one-dimensional motion where an object moves along a straight path. Key concepts include:

1. Displacement (x): Change in position of the object.

2. Velocity (v): Rate of change of displacement.

3. Acceleration (a): Rate of change of velocity.

Formulae:

1. Average Velocity (v) = Δx / Δt

2. Instantaneous Velocity (v) = dx / dt

3. Average Acceleration (a) = Δv / Δt

4. Instantaneous Acceleration (a) = dv / dt

5. Kinematic equations for uniformly accelerated motion:

   • v = v₀ + at

   • x = v₀t + (1/2)at²

   • v² = v₀² + 2ax

Procedure:

1. Set up the straight track and mark equal distances (0 m, 0.5 m, 1 m, 1.5 m, etc.).

2. Place the toy car at the starting point (0 m).

3. Release the car without pushing (let it roll naturally).

4. Start the stopwatch as the car begins to move.

5. Note the time at each marked distance.

6. Repeat the experiment thrice for accuracy and take the average of the time readings.

7. Record the observations in a table.

8. Plot a distance-time graph.

9. Calculate velocity and acceleration using the recorded values and the formulae.

Observations: Record the distance and time readings in a table as follows:

Distance (m)	Time (s)	Average Time (s)	Velocity (m/s)	Acceleration (m/s²)

Calculations:

1. Calculate the average time for each distance.

2. Determine the velocity using the formula v = Δx / Δt.

3. Calculate acceleration using the formula a = Δv / Δt.

Graph: Plot a distance-time graph and velocity-time graph using the values obtained.

Result:

1. The calculated average velocity is ______.

2. The calculated average acceleration is ______.

3. The distance-time graph is a straight line (if uniform motion).

Precautions:

1. Ensure the track is smooth and straight.

2. Avoid any external push to the object.

3. Start and stop the stopwatch accurately.

Conclusion: The experiment verifies the concepts of motion in a straight line and helps in understanding displacement, velocity, and acceleration practically.

HS 1st year Physics Chapter 1: Experiments

 Title: Experiment on the Heating Effect of Electric Current

Introduction: Host: Welcome, everyone! Today, we will conduct an exciting experiment to demonstrate the Heating Effect of Electric Current.

Materials Required: Host: To perform this experiment, we need:

• A nichrome wire

• A battery

• A switch

• Connecting wires

• A bulb

• A heatproof stand

Setup: Host: We will set up the circuit by connecting the nichrome wire to the battery using the connecting wires. The bulb will be placed in the circuit to indicate the passage of current.

Procedure: Host: Let’s begin!

1. Connect the nichrome wire to the battery using the connecting wires.

2. Include the bulb in the circuit.

3. Now, switch on the battery.

Observation: Host: As the current passes through the nichrome wire, the bulb glows, and the nichrome wire starts to heat up. This demonstrates the Heating Effect of Electric Current.

Explanation: Host: The heating effect of electric current occurs because the electrical energy is converted into heat energy in the conductor. The nichrome wire, being a good conductor of heat, gets heated up, and the bulb glows.

Conclusion: Host: This experiment clearly shows that when an electric current passes through a conductor, it generates heat. This is known as the Heating Effect of Electric Current.

Thank You: Host: Thank you, everyone, for being a part of this experiment. Keep exploring and learning new concepts. Have a great day!

Chemistry HS2 unit 1 Question & Answer

1. Types of Solutions

Q1. What are binary solutions?
A1. Solutions with two components are called binary solutions.

Q2. What is the difference between solid in liquid and gas in liquid solutions?
A2. In solid in liquid solutions, a solid solute dissolves in a liquid solvent (e.g., sugar in water), while in gas in liquid, a gas solute dissolves in a liquid solvent (e.g., CO₂ in soda).

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2. Expressing Concentration of Solutions

Q1. What are the different methods of expressing concentration of a solution?
A1. Concentration can be expressed as mass percent, volume percent, mole fraction, molarity, and molality.

Q2. How is molarity defined?
A2. Molarity is the number of moles of solute dissolved in one litre of solution.

Q3. What is the unit of molality?
A3. Molality is expressed in mol/kg.

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3. Solubility

Q1. What is solubility?
A1. Solubility is the maximum amount of a substance that can be dissolved in a given amount of solvent at a specific temperature.

Q2. What factors affect solubility?
A2. Solubility is affected by temperature, nature of solute and solvent, and pressure (in the case of gases).

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4. Solubility of Gases in Liquids – Henry’s Law

Q1. What does Henry's Law state?
A1. Henry’s Law states that the solubility of a gas in a liquid is directly proportional to the pressure of the gas above the liquid.

Q2. Why do scuba divers use a mixture of oxygen and helium?
A2. To avoid the toxic effects of high nitrogen concentration under pressure, helium is used to dilute the oxygen.

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5. Vapour Pressure of Liquid Solutions

Q1. What is Raoult’s Law?
A1. Raoult’s Law states that the partial vapour pressure of each volatile component in a solution is directly proportional to its mole fraction.

Q2. How does vapour pressure vary in ideal solutions?
A2. In ideal solutions, vapour pressure varies linearly with mole fraction.

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6. Ideal and Non-Ideal Solutions

Q1. What characterizes an ideal solution?
A1. An ideal solution obeys Raoult’s Law at all concentrations and shows no change in enthalpy or volume upon mixing.

Q2. Give an example of a non-ideal solution with negative deviation.
A2. A mixture of acetone and chloroform shows negative deviation due to hydrogen bonding.

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7. Colligative Properties

Q1. What are colligative properties?
A1. Colligative properties depend on the number of solute particles, not their nature.

Q2. Name the four colligative properties.
A2. Relative lowering of vapour pressure, elevation of boiling point, depression of freezing point, and osmotic pressure.

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8. Determination of Molar Mass using Colligative Properties

Q1. How can molar mass be determined using freezing point depression?
A1. By measuring the depression in freezing point and using the formula involving the cryoscopic constant.

Q2. What is the van’t Hoff factor?
A2. It is the ratio of the observed colligative property to the calculated one, accounting for dissociation or association.

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9. Abnormal Molar Masses

Q1. What causes abnormal molar masses?
A1. Association or dissociation of solute molecules in solution leads to abnormal molar masses.

Q2. How does the van’t Hoff factor correct for abnormal molar masses?
A2. It adjusts the calculated molar mass by considering the actual number of particles in solution.

Chemistry Unit 2 Electrochemistry HS 2nd year

 

Experiment 1: Construction and Working of a Daniell Cell

Objective:
To demonstrate the working of a galvanic cell using Zn and Cu electrodes and measure its emf.

Materials Required:

• Zinc rod

• Copper rod

• 1M ZnSO₄ solution

• 1M CuSO₄ solution

• Salt bridge (e.g., KCl in agar-agar)

• Voltmeter

• Wires and alligator clips

Procedure:

1. Prepare two half-cells: one with Zn rod in ZnSO₄ solution and the other with Cu rod in CuSO₄ solution.

2. Connect the two half-cells using the salt bridge.

3. Connect the zinc electrode to the negative terminal and copper to the positive terminal of the voltmeter using wires.

4. Record the emf of the cell.

Observation:
The voltmeter shows an emf around 1.1V.

Conclusion:
This cell converts chemical energy from the redox reaction into electrical energy.

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Experiment 2: Determination of Cell Potential Using Nernst Equation

Objective:
To determine the emf of a cell at non-standard conditions using the Nernst equation.

Reaction:
Zn(s) + Cu²⁺(aq) → Zn²⁺(aq) + Cu(s)

Given:

• Standard emf (E°) = 1.10 V

• [Cu²⁺] = 0.1 M, [Zn²⁺] = 1.0 M

Procedure:

1. Use the Nernst equation:

   $$E_{cell} = E° - \frac{0.059}{2} \log\left(\frac{[Zn^{2+}]}{[Cu^{2+}]}\right)$$

2. Substitute the values into the formula.

3. Calculate the emf.

Calculation:

$$E_{cell} = 1.10 - \frac{0.059}{2} \log(10) = 1.10 - 0.0295 = 1.0705\ V$$

Conclusion:
The emf decreases when the concentration of Cu²⁺ decreases.

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Experiment 3: Determination of Conductivity of an Electrolytic Solution

Objective:
To measure the conductivity of a KCl solution using a conductivity meter.

Materials Required:

• Conductivity cell

• 0.1 M KCl solution

• Conductivity meter

• Thermometer

Procedure:

1. Calibrate the conductivity cell using standard KCl solution.

2. Rinse the conductivity cell and fill with the KCl solution.

3. Measure the resistance using the meter.

4. Calculate conductivity using:

   $$\kappa = \frac{G^*}{R}$$

   where $G^*$ is the cell constant.

Observation & Conclusion:
Conductivity value is recorded. It depends on ion concentration and temperature.

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Experiment 4: Electrolysis of Copper Sulphate Solution

Objective:
To demonstrate electrolysis using CuSO₄ solution and copper electrodes.

Materials Required:

• Copper electrodes

• 1M CuSO₄ solution

• DC power supply

• Beaker, connecting wires

Procedure:

1. Fill the beaker with CuSO₄ solution and insert copper electrodes.

2. Connect the electrodes to the power supply (cathode to negative terminal).

3. Pass current for a fixed time (e.g., 15 minutes).

4. Observe deposition at the cathode and dissolution at the anode.

Observation:
Copper is deposited on the cathode, and the anode dissolves.

Conclusion:
This demonstrates Faraday’s laws of electrolysis.