THE UNIVERSITY OF TEXAS RIO GRANDE VALLEY
Department of Chemistry
CHEM 4304 — Instrumental Analysis
Spring 2026
Presentation Cases: Characterizing Unknown Samples
1. Project Overview
Each team is composed of 4 students and will be assigned a set of pre-collected spectral data from an
unknown chemical compound. This is not a laboratory experiment — no physical sample is handled.
The task is entirely analytical: interpret the provided spectra and identify the compound.
This project accounts for 17.5% of the final course grade. All team members are expected to contribute
equally to both the analysis and the oral presentation.
Presentation date: Tuesday, May 5, 2026. Teams have one month from the date of data assignment to
analyze all spectra, propose a structure, and prepare the final presentation.
2. Objective
Using a provided set of spectral data, determine the structure and identity of an unknown chemical
compound by interpreting results from:
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UV-Visible Spectroscopy (UV-Vis)
Photoluminescence (PL)
Fourier Transform Infrared Spectroscopy (FTIR)
Nuclear Magnetic Resonance — ¹H and ¹³C NMR
Mass Spectrometry (MS)
The final deliverable is a 10-minute PowerPoint presentation in which the team interprets each
spectrum and builds a coherent case for the proposed molecular structure.
3. Team Organization
Each team consists of 4 students. The following role distribution is suggested to ensure all spectra are
covered systematically:
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Student 1 – UV-Vis and Photoluminescence spectrum analysis
Student 2 – FTIR spectrum analysis and functional group identification
Student 3 – NMR data interpretation (¹H and ¹³C chemical shifts, multiplicity, integration)
Student 4 – Mass Spectrometry analysis and coordination of the final structural proposal
Important: All four students must be ready to answer questions on any section of the presentation during
the Q&A.
5. Presentation Structure
The presentation must include 6–7 slides (approximately 0.5 minutes per slide):
Slide
1
Topic
Introduction
2
UV-Vis & PL
3
FTIR
4
NMR
5
6
Mass Spectrometry
Proposed Structure
7
Conclusion & Q&A
Expected Content
Sample code, spectral dataset overview, initial hypothesis on
compound identity
λmax values, bathochromic shifts, emission peaks and Stokes
shift interpretation
Key absorption peaks (OH, C=O, C=C, N-H, etc.) and
functional group assignment
Proton and carbon chemical shifts, multiplicity, integration —
connectivity analysis
Molecular ion peak, fragmentation pattern, isotopic distribution
Structural drawing with justification for every spectral feature
observed
Final summary of evidence and open discussion with the class
6. Analytical Techniques Toolbox
The following table summarizes what each type of spectral data reveals:
Technique
UV-Vis
Photoluminescence
(PL)
FTIR
NMR (¹H, ¹³C)
Mass Spectrometry
(MS)
What the Spectrum Tells You
Degree of conjugation, chromophores, π→π* and n→π* electronic transitions
Fluorescent groups, Stokes shift, emission wavelength relative to absorption
Functional groups present (bonds) identified by characteristic absorption
frequencies
Chemical environment of H and C atoms, connectivity, splitting patterns,
integration
Molecular weight, fragmentation pathway, isotopic patterns for heteroatom
detection
7. Grading Criteria
This project is worth 17.5% of the total course grade and will be evaluated as follows:
Category
PowerPoint Design
Interpretation of Spectral Data
Structural Proposal Accuracy
Oral Delivery & Teamwork
Q&A Response
TOTAL
Weight
10%
30%
25%
25%
10%
100%
Points (out of 100)
10
30
25
25
10
100
8. Tips for Success
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Include annotated spectra in your slides — label every key peak you reference
Show how each spectral signal supports your proposed structure; build the argument step by step
Do not just read the data — explain what it means chemically
Use ChemDraw or similar software to draw accurate molecular structures
Practice your timing: the presentation must not exceed 3 minutes
Coordinate with your team on who handles which questions during Q&A
Be clear, confident, and scientifically curious in your delivery
CHEM 4304 — Instrumental Analysis | Spring 2026 | UTRGV
Presentation Date: May 5, 2026 | Worth: 17.5% of Final Grade