ASSIGNMENT

ANALYTICAL METHODS IN CHEMISTRY

Course Code: BCHET-141

Assignment Code: BCHET-141/TMA/2024
Maximum Marks: 100

Note: Attempt all questions. The marks for each question are indicated against it.

Par A (50 marks)

1 Writ the procedure for the collection and preservation of water samples. (5)
2 Define Indeterminate errors. How we can reduce them. (5)

3 What is significance of t-test? Explain using a suitable example. (5)

4 Which reagents are used for extraction by solvation? Give suitable examples. (5)

5 Briefly explain the extraction by chelation. Also give some examples of the chelating (5)
agents used.

6 Explain continuous extraction with the help of a suitable diagram. Which factors govern (5)
the efficiency of such extractions?

7 Draw a flow chart for the classification of various types of chromatographic techniques. (5)

8 List different criteria for choosing the mobile phase used in paper chromatography. (5)

9 Discuss the principle of coloumn chromatography illustrating the experimental setup. (5)

10 Briefly explain various types of capacities associated with ion exchangers. (5)

Par B (50 marks)

11 Discuss the factors which limit the accuracy of pH measurements. (5)

12 Discuss design and working of silver-silver chloride electrode. (5)

13 How the conductance is varies with concentration? Explain with the help of (5)
suitable examples.
14 Explain ionic nobilities and transport number. (5)
15 Taking suitable examples explain the effect of furnace atmosphere on TG curves. (5)
16 An impure sample of CaC2O4  H2O is analyzed using TGA technique. TG curve (5)
of the sample indicates the total mass change from 85 mg to 30.7 mg when this
sample was heated up to 1173 K. calculate the purity of the sample.
17 Write the shortcomings of wave model of electromagnetic radiation. Describe the (5)
model that was able to explain these shortcomings.
18 Write the expression of Lambert’s and Beer’s law. List the factors responsible for (5)
the deviation from Beer-Lambert’s law.
19 What is the necessary condition for observing IR spectrum? Describe in brief the (5)

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 types of vibrations for a polyatomic molecule.
20 How are the signals in an atomic spectrum characterized? Illustrate your answer. (5)

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BCHET-141
SOLVED ASSIGNMENT 2024

Q.1 - Writ the procedure for the collection and preservation of

water samples.
ANS.- Collecting and Preserving Water Samples: A Precise Procedure
Proper collection and preservation are crucial for accurate water analysis. Here's a general procedure,
but always consult specific requirements for your analysis parameters:
1. Preparation:
 Gather tools: Choose appropriate sample bottles based on analysis needs
(e.g., glass/plastic, volume). Ensure cleanliness and pre-rinse with distilled water if
necessary. Pack coolers with ice packs and a thermometer. Wear gloves and safety glasses.
 Identify sampling site: Select a representative location free from potential contamination
sources. Note weather conditions, time, and any relevant details.
2. Sample Collection:
 Surface water: Submerge the bottle just below the surface, facing the current (if any). Avoid
surface film or bottom sediments. Fill completely, leaving minimal headspace.
 Groundwater: Use dedicated well pumps or bailers to avoid disturbing sediments. Collect from
several locations within the well for a composite sample.
 Other sources: Adapt the approach based on the source (e.g., using sterile syringes for sediment
porewater).
3. Preservation:
 Temperature: Immediately chill samples on ice to 4°C (ideally) or below to slow biological activity.
 Chemical: Depending on analysis, add specific preservatives (e.g., acids for metals, bases for
organics) as per lab instructions. Wear appropriate personal protective equipment while handling
chemicals.
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 Light: Protect samples from sunlight to prevent degradation of certain analytes.

4. Labeling and Transportation:
 Label each bottle clearly: Include date, time, location, sample type, preservative used (if any), and
your name. Use waterproof ink.
 Maintain chain of custody: Document sample handling (e.g., temperature log).
 Transport promptly: Deliver samples to the lab within the recommended timeframe (usually
within 24-48 hours).

Q.2- Define Indeterminate errors. How we can reduce them

ANS.- Indeterminate errors, also called random errors, are like whispers in a crowded room - small,
unpredictable fluctuations that make your measurements deviate from the true value. Unlike their systematic
cousins, these whispers have no consistent pattern, making them difficult to isolate and eliminate.
They arise from numerous sources, often uncontrollable: slight variations in temperature, instrument
noise, even a shaky hand while pipetting. These whispers tend to average out with repeated
measurements, but can still create a hazy outline around your true result.
So, how to silence these whispers? Here are some tips:
 Repeat, repeat, repeat: The more measurements you take, the more likely the random whispers
cancel each other out, revealing a clearer picture of the true value.
 Control the controllables: Minimize known sources of variation by calibrating
instruments, maintaining constant temperatures, and using proper technique.
 Statistical magic: Tools like standard deviation help quantify the "fuzziness" of your
measurements, giving you an idea of their reliability.
Remember, even with our best efforts, some whispers will always linger. But by employing these
strategies, we can turn the crowded room into a quiet corner, revealing the true voice of our data.

Q.3 - What is significance of t-test? Explain using a suitable

example.
ANS.-
Here's the significance of t-tests, illustrated with an example:
T-tests are invaluable statistical tools that assess whether the means of two groups differ significantly.
They provide evidence for making informed decisions in various fields, including research, medicine,
business, and education.
Significance:
1. Hypothesis Testing: They rigorously test assumptions about populations using sample
data, guiding conclusions and actions.
2. Measuring Treatment Effects: They evaluate the effectiveness of interventions, therapies, or
programs.
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3. Comparing Groups: They illuminate differences between groups, identifying potential

relationships or disparities.
4. Data-Driven Decisions: They promote evidence-based decision-making, ensuring sound choices in
various domains.
Example: Evaluating a New Drug:
 Research Question: Does a new drug effectively lower blood pressure compared to a placebo?
 T-test Setup:
o Null Hypothesis (H₀): The drug has no effect on blood pressure (means are equal).
o Alternative Hypothesis (H₁): The drug lowers blood pressure (mean blood pressure in the
drug group is lower).
 Data Collection: Measure blood pressure in two groups: one receiving the drug and one receiving
a placebo.
 T-test Calculation: Compute the t-statistic and p-value, quantifying the difference between the
means and its likelihood of occurring by chance.
 Interpretation:
o If the p-value is below a significance threshold (e.g., 0.05), reject H₀ and conclude the drug
likely lowers blood pressure.
o If the p-value is above the threshold, fail to reject H₀, suggesting insufficient evidence to
support the drug's effectiveness.
T-tests provide a cornerstone for statistical inference, enabling researchers and professionals to draw
meaningful conclusions from data and make informed decisions that impact various aspects of life.

Q.4- Which reagents are used for extraction by solvation? Give

suitable examples
ANS.- The reagents used for extraction by solvation depend on the target molecule and the solvent chosen.
However, some general groups of reagents play frequent roles:
1. Acids & Bases:
 For metal ions: Acids like hydrochloric acid can protonate and solubilize metal ions in aqueous
solutions, making them easier to extract into organic solvents. Conversely, bases like amines can
bind and complex certain metal ions, enhancing their solubility in organic solvents.
 For organic molecules: Acids and bases can adjust the pH to promote protonation or
deprotonation of target molecules, altering their polarity and facilitating extraction into specific
solvents.
2. Salting-out agents:
 Highly soluble salts like sodium chloride can increase the ionic strength of the aqueous
phase, "salting out" polar molecules from the water and driving them into the organic phase. This
is particularly useful for extracting proteins and other biomolecules.
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3. Complexing agents:
 Crown ethers, cryptands, and other specialized ligands can selectively bind and "encapsulate"
specific target molecules, enhancing their solubility in chosen organic solvents. This is widely used
in the separation and purification of pharmaceuticals and other high-value compounds.
Examples:
 Uranium extraction: Tributyl phosphate (TBP) in kerosene extracts uranium(VI) ions from nitric
acid solutions through complexation.
 Caffeine extraction: Dichloromethane readily extracts caffeine from acidic coffee solutions due to
its neutral polarity and caffeine's amphoteric nature.
 Protein purification: Polyethylene glycol (PEG) can be used to "salt out" proteins from aqueous
solutions in a controlled manner, facilitating their isolation and purification.
These are just a few examples, and the specific reagents used will vary greatly depending on the target
molecule and desired outcome.

Q.5 - Briefly explain the extraction by chelation. Also give some

examples of the chelating agents used.
ANS.- Extraction by Chelation: Selective Grabbing with Claws
Chelation extraction is a technique that uses chelating agents to selectively bind and extract specific
metal ions from a mixture. Imagine the chelating agent as a crab-like claw, firmly grasping its target
metal ion in a stable hug. This "hug" is formed through strong bonds between the agent's donor atoms
(typically nitrogen, oxygen, or sulfur) and the metal ion's empty orbitals.
The Key Steps:
1. Choose your chelating agent: Different agents have different preferences for specific metal
ions. Common examples include:
o EDTA (ethylenediaminetetraacetic acid): A versatile claw with six "arms" for strong
binding to various metals.
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EDTA chelating agent

o Dithiocarbamates: Effective for extracting heavy metals like copper and mercury.
Dithiocarbamate chelating agent
o Crown ethers: Ring-shaped agents with specific size and charge for selective binding.

Crown ether chelating agent

2. Mix it up: Add the chelating agent to the solution containing the desired metal ion.
3. The chelation dance: The agent binds to the target metal ion, forming a stable complex.
4. Separation stage: This can involve various techniques like solvent extraction, precipitation, or
filtration, depending on the chosen agent and solution properties.
Benefits of Chelation Extraction:
 High selectivity: Targets specific metal ions, leaving others behind.
 Efficiency: Effective at low metal ion concentrations.
 Versatility: Applicable to various metals and solutions.
Applications:
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 Metal recovery: Extracting valuable metals from ores and industrial waste.
 Pollution control: Removing toxic metals from wastewater.
 Medicine: Chelation therapy for treating heavy metal poisoning.
By understanding the "clawing" power of chelation, we can harness this technique for various purposes,
from environmental cleanup to targeted medical interventions.

Q.6- Explain continuous extraction with the help of a suitable

diagram. Which factors govern the efficiency of such extractions?
ANS.- Continuous Extraction: A Flowing Journey to Enhanced Yields
In contrast to batch extraction, continuous extraction boasts superior efficiency and throughput. This
dynamic process continuously feeds and processes the mixture, maximizing target compound recovery.
Imagine a cascading counter-current flow, akin to a multi-tiered waterfall. The feed mixture descends,
while the extraction solvent ascends, encountering each other at each stage for optimal extraction.
Schematic:

Efficiency Drivers:
 Stage number and contact time: Increasing the number of stages (rungs) enhances contact
between solvent and target compound, leading to higher yields.
 Flow rate ratio: Optimizing the flow rates of feed and solvent ensures efficient mass transfer
within each stage.
 Solvent selectivity: Choosing a solvent with high affinity for the target compound maximizes
extraction while minimizing co-extraction of impurities.
 Thermo-dynamic control: Precise temperature and pressure control can significantly influence
solubility and mass transfer, impacting overall efficiency.
 Mixing intensity: Thorough mixing at each stage ensures complete interaction between the feed
mixture and solvent, maximizing extraction potential.
Continuous extraction's advantages are numerous, including reduced solvent consumption, improved
product purity, and real-time process monitoring. By meticulously controlling the efficiency-governing
factors, this technique can be optimized for diverse applications in various industries, from
pharmaceuticals to food processing.
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Q.7 - Draw a flow chart for the classification of various types of

chromatographic techniques.
ANS.- Chromatographic techniques encompass diverse methods like Gas Chromatography (GC), Liquid
Chromatography (LC), Thin-Layer Chromatography (TLC), and High-Performance Liquid Chromatography
(HPLC). These techniques separate compounds based on their interactions with the mobile and
stationary phases. GC separates volatile compounds, LC separates non-volatile substances, TLC employs
a thin adsorbent layer, and HPLC offers high resolution and sensitivity in separating components.

Q.8- List different criteria for choosing the mobile phase used in
paper chromatography.
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ANS.- Continuous Extraction: Streamlining Efficiency

In contrast to batch methods, continuous extraction employs a counter-current flow system for
unparalleled efficiency and yield. Imagine a multi-stage apparatus where the feed mixture descends like
a cascade, meeting an ascending stream of extraction solvent at each contact point. This maximizes
interaction and optimizes mass transfer, resulting in cleaner separation.
Key Efficiency Drivers:
 Staggered Counter-Current Flow: Higher stage numbers increase contact between solvent and
target compound, promoting thorough extraction.
 Flow Rate Optimization: Balancing feed and solvent flow rates ensures optimal residence time
within each stage, maximizing extraction at each level.
 Solvent Selectivity: Choosing a solvent with high affinity for the target compound while
minimizing interaction with undesired components allows for cleaner extracts.
 Thermo-dynamic Control: Tuning temperature and pressure influences solubility and mass
transfer, impacting extraction efficiency.
 Enhanced Mixing: Efficient mixing within each stage ensures all feed components come into
contact with the solvent, further improving yield.
Continuous extraction boasts several advantages, including minimized solvent consumption, improved
product purity, and real-time process monitoring. By optimizing the key factors affecting its efficiency,
this powerful technique can be tailored for diverse applications across various industries.

Q.9 - Discuss the principle of coloumn chromatography illustrating

the experimental setup.
ANS.- Column chromatography is a separation technique based on differential partitioning of compounds
between a stationary phase and a mobile phase. The setup typically involves a vertical glass column filled with a
stationary phase, often silica or alumina.
The experimental setup begins by packing the column with the stationary phase, which is often pre-
treated and filled uniformly to ensure proper separation. A slurry of the stationary phase in a suitable
solvent is prepared and poured into the column. This is followed by the addition of a small amount of
sand or cotton to create an even surface.
The sample mixture, dissolved in the mobile phase (solvent), is then carefully loaded onto the top of the
column. As the mobile phase percolates through the column, compounds within the mixture interact
differently with the stationary phase based on their affinities, leading to separation.
The elution process involves passing the mobile phase through the column, collecting fractions
containing separated compounds. The components with higher affinity for the stationary phase elute
later, while those with less affinity elute earlier, resulting in the isolation of different compounds based
on their partitioning behavior.
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Q.10- Briefly explain various types of capacities associated with

ion exchangers.
ANS.- Ion exchangers exhibit diverse capacities crucial in various processes:
1. Exchange Capacity: It denotes the quantity of ions an exchanger can adsorb or exchange. It's a
fundamental measure indicating the exchanger's ability to swap ions.
2. Total Capacity: This refers to the maximum number of ions an exchanger can hold when
completely saturated. It accounts for all available binding sites.
3. Selectivity: It defines the preference an ion exchanger shows towards specific ions during the
exchange process. Some exchangers favor certain ions over others based on size, charge, or
chemical properties.
4. Loading Capacity: It signifies the actual quantity of ions currently present on the exchanger. It's
crucial in practical applications where controlling the amount of exchanged ions is necessary.
5. Regeneration Capacity: It pertains to the ability to restore the ion exchanger's functionality after
saturation by removing the adsorbed ions, enabling its reuse.
Understanding these capacities aids in optimizing ion exchange processes for various applications like
water treatment, chemical purification, and more.

PART B
Q.11 - Discuss the factors which limit the accuracy of pH
measurements.
ANS.- The accuracy of pH measurements can be compromised by several factors, both related to the
instrument and the sample itself. Instrument limitations include:
 Temperature: pH electrodes are sensitive to temperature changes, requiring calibration
adjustments or built-in compensation for accurate readings.
 Electrode condition: Contamination, aging, or damage to the glass membrane or reference
electrode can alter the measured potential.
 Calibration: Improper calibration using expired buffers or buffers with incorrect ionic strength can
skew the entire measurement range.
Sample-related factors include:
 Ionic strength: High salt concentrations can interfere with the electrode's response, requiring
specialized electrodes or ionic strength adjusters.
 Redox potential: Strong oxidizing or reducing agents can influence the electrode
potential, making accurate readings difficult.
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 Viscous liquids: Thick samples can clog the reference junction, leading to unstable readings.
 CO2 interference: Dissolved carbon dioxide in water can affect acidic readings, requiring
degassing or special electrodes.
Minimizing these limitations involves proper instrument calibration and maintenance, careful sample
preparation, and choosing electrodes suitable for the specific sample matrix.
By understanding these factors and implementing proper procedures, we can ensure accurate and
reliable pH measurements.

Q.12- Discuss design and working of silver-silver chloride

electrode.
ANS.- The silver-silver chloride electrode is a crucial component in electrochemical measurements, particularly
in pH determination and other analytical applications. Its design involves a silver wire coated with silver chloride.
This electrode operates on the principle of the reversible redox reaction between silver and silver chloride.
The electrode's working involves establishing equilibrium between the silver and silver chloride, creating
a stable potential. When in contact with a chloride-containing solution, a layer of silver chloride forms on
the electrode's surface due to the reaction between the silver and chloride ions. This formation
maintains a constant chloride concentration at the electrode surface, ensuring stable potential.
The electrode's potential remains stable because of the equilibrium between the silver ions from the
electrode and the chloride ions from the solution. This stability allows for precise and consistent
measurements in various electrochemical processes, making the silver-silver chloride electrode a
fundamental tool in analytical chemistry.

Q.13 - How the conductance is varies with concentration? Explain

with the help of suitable examples.
ANS.-
Conductance, the ability of a material to conduct electricity, changes significantly with concentration in electrolytic
solutions. In general, as concentration increases, conductance also increases. This seems intuitive, as more ions
are present to carry the current. However, the relationship isn't linear.
Strong electrolytes, like NaCl, fully dissociate into ions even at low concentrations. Increasing
concentration initially boosts conductance linearly due to more charge carriers. However, at higher
concentrations, ion crowding and interionic interactions hinder movement, causing conductance to rise
slower or even plateau.
Weak electrolytes, like acetic acid, partially dissociate into ions. With increasing concentration, the
dissociation degree initially increases, leading to higher conductance. However, beyond a certain point,
further concentration increases mainly affect undissociated molecules, not contributing to conductance.
This results in a non-linear rise and eventually a plateau.
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Examples:
 Seawater: High salt concentration makes it a good conductor.
 Battery acid: Dilution reduces its conductivity, impacting its efficiency.
 Blood: Its plasma's electrolyte balance is crucial for proper nerve transmission.
Understanding how conductance varies with concentration is crucial in various fields, from designing
efficient batteries to studying biological processes.

Q.14- Explain ionic nobilities and transport number.

ANS.- Ionic nobilities refer to the inherent tendency of ions to migrate towards electrodes in an electrolyte
solution under the influence of an electric field. Each ion possesses a specific mobility or ionic nobility, which
dictates its speed and ease of movement in the solution. The nobility of an ion depends on factors such as its size,
charge, and the viscosity of the medium.
Transport number, on the other hand, relates to the fraction of the total current carried by a specific ion
in the electrolyte solution. It signifies the efficiency of an ion in conducting electricity within the solution.
The transport number is a crucial parameter in understanding the individual contribution of ions to the
overall conductivity of the solution. It is determined experimentally and helps predict the behavior of
ions in various electrochemical processes, including electrolysis and battery operation.

Q.15 - Taking suitable examples explain the effect of furnace

atmosphere on TG curves.
ANS.- The furnace atmosphere can dramatically alter the shape and information gleaned from thermo
gravimetric analysis (TGA) curves. Let's explore this through two examples:
1. Calcium carbonate decomposition: In an inert atmosphere like nitrogen, calcium carbonate
decomposes to calcium oxide and carbon dioxide around 800°C, causing a single mass drop on the TG
curve. But introduce air (containing oxygen), and the story changes. Calcium oxide can further react with
CO2 to form calcium carbonate again, leading to a plateau or even a mass gain at higher temperatures.
This reveals the complex interplay between decomposition and re-formation in oxidizing environments.
2. Polymer oxidation: Consider a polyethylene sample. In air, the TG curve will show a sharp mass loss
starting around 350°C due to rapid chain scission and oxidation. However, in an inert atmosphere like
helium, degradation occurs much slower and at higher temperatures. This showcases the crucial role of
oxygen in promoting thermal breakdown for certain materials.
These examples highlight how furnace atmosphere influences the reaction pathways and kinetics,
impacting the TG curve's shape, decomposition temperatures, and overall interpretation. Choosing the
right atmosphere is crucial for obtaining accurate insights into a material's thermal behavior.
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Q.16-

ANS.- The compound CaC2O4·H2O (calcium oxalate monohydrate) decomposes upon heating to form
CaC2O4 (calcium oxalate) and H2O (water). The molar mass of CaC2O4·H2O is 146.11 g/mol and that of
CaC2O4 is 128.10 g/mol.
The mass loss during heating is due to the loss of water. The mass of water in one mole of CaC 2O4·H2O is
18.01 g (the molar mass of water).
So, the theoretical mass loss upon heating one mole of CaC 2O4·H2O is 18.01 g, which is a 12.33% loss
(18.01 g / 146.11 g x 100%).
In the experiment, the mass loss was from 85 mg to 30.7 mg, which is a 63.88% loss (54.3 mg / 85 mg x
100%).
The purity of the sample can be calculated as the ratio of the experimental mass loss to the theoretical
mass loss: 63.88% / 12.33% = 518.06%.
Q.17 - Write the shortcomings of wave model of electromagnetic
radiation. Describe the model that was able to explain these
shortcomings.
ANS.- The wave model, while highly successful in explaining electromagnetism, stumbled upon phenomena like
the photoelectric effect and black body radiation. It predicted continuous energy transfer at any frequency, failing
to explain why metals eject electrons only above a certain threshold light frequency. Similarly, it couldn't account
for the observed peak wavelengths for hot objects' radiation.
Enter the revolutionary quantum model by Max Planck. He proposed that energy is emitted and
absorbed in discrete "packets" called quanta, later renamed photons. This elegantly solved the
discrepancies. The photoelectric effect became a matter of photon energy causing electron ejection, and
black body radiation found explanation in quantized energy states of vibrating atoms. While the wave
model remains crucial for understanding propagation and properties of light, the quantum model
unveiled the microscopic nature of light-matter interaction, opening the door to a whole new realm of
physics.

Q.18- Write the expression of Lambert’s and Beer’s law. List the
factors responsible for the deviation from Beer-Lambert’s law.
ANS.-
Laws of Absorption:
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 Lambert's Law (Path Length Law): A = εcL

This states that the absorbance (A) is directly proportional to the path length (L) the light travels through
the absorbing medium.
 Beer's Law (Concentration Law): A = εc
This states that the absorbance is directly proportional to the concentration (c) of the absorbing species.
Combined Beer-Lambert Law:
A = εcL
This law combines Lambert's and Beer's laws, where ε is the molar absorptivity, a constant specific to the
absorbing species and wavelength.
Deviations from Beer-Lambert's Law:
 Concentration-dependent effects:
o Intermolecular interactions like aggregation/dimerization alter ε.
o Chemical equilibria affect the absorbing species concentration.
 Light scattering by the medium: Dilute solutions usually do not exhibit this.
 Changes in refractive index with concentration: Alters light path length.
 Non-monochromatic light: Requires averaging over a range of ε values.

Q.19 - What is the necessary condition for observing IR spectrum?

Describe in brief the types of vibrations for a polyatomic molecule.
ANS.-
Observing the Dance of Molecules: IR Spectrum Essentials
To witness the infrared (IR) spectrum of a molecule, it must interact with infrared radiation. This means
the molecule needs to possess vibrational modes whose energy changes match the frequencies of IR
light. Essentially, the molecule must "dance" in a way that resonates with the IR waves.
For polyatomic molecules, the dance gets complex. They can vibrate in various ways, categorized as:
 Stretching vibrations: Atoms within a bond rhythmically move closer and further apart, like two
partners swaying in a waltz.
 Bending vibrations: Bonds within a molecule bend and straighten, akin to a hula dancer's hip
movements.
 Wagging vibrations: A group of atoms pivots back and forth like a wagging tail.
 Rocking vibrations: Atoms within a molecule tilt sideways, resembling a seesaw in motion.
 Twisting vibrations: Atoms in a molecule rotate around a central bond, similar to a twisting torso.
Each of these vibrations has a specific energy level, and only those matching IR frequencies will be
absorbed, leaving their mark on the spectrum. By analyzing these absorption peaks, we can identify the
molecule's functional groups and gain valuable insights into its structure and dynamics.
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Q.20- How are the signals in an atomic spectrum characterized?

Illustrate your answer.
ANS.-
The signals in an atomic spectrum, also known as spectral lines, are characterized by their wavelength, intensity,
and fine structure.
 Wavelength: Each spectral line corresponds to a specific wavelength of light emitted or absorbed
by an atom. This wavelength is directly related to the energy difference between two electronic
states in the atom. Shorter wavelengths correspond to higher energy transitions.
 Intensity: The intensity of a spectral line indicates the relative number of atoms undergoing the
corresponding transition. Stronger lines represent more frequent transitions, while weaker lines
indicate less frequent transitions.
 Fine structure: Some spectral lines exhibit fine structure, which is a splitting of the line into
multiple closely spaced components. This fine structure arises from interactions between the
electrons and the nucleus, or from the presence of an external magnetic field.
Here's an illustration to help visualize these characteristics:

Atomic emission spectrum diagram

In this diagram, the horizontal axis represents the wavelength of light, and the vertical axis represents
the intensity of the emitted light. Each peak on the spectrum corresponds to a specific spectral line, with
its wavelength indicated on the horizontal axis and its intensity represented by the height of the peak.
The fine structure of some lines is also visible as a splitting of the peaks into multiple components.
By analyzing the characteristics of spectral lines, scientists can gain valuable information about the
structure and properties of atoms. For example, the wavelengths of spectral lines can be used to identify
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the element present in a sample, while the intensity of lines can be used to determine the abundance of
different isotopes of that element. The fine structure of spectral lines can also be used to study the
interactions between electrons and the nucleus, providing insights into the fundamental nature of
matter.