levo

Organic Synthesis, NMR and Chromatography

TMS and Deuterated Solvents

  • 3 things to know
  • Papers 2 and 3

Overview

Why TMS is the reference, and why the solvent must contain no ordinary hydrogen.

What you need to know

Answer each one before you reveal it.

Your recallNot started
Key term

What is the molecular formula of TMS?

Key term

Why does TMS produce a single sharp peak in both ¹H NMR and ¹³C NMR spectra?

Key term

Why is the chemical shift of TMS defined as zero on the δ scale?

Questions from this subtopic

Each one with the model answer underneath.

  1. 1

    What compound is used as the reference standard in NMR spectroscopy?

    Model answer

    Tetramethylsilane (TMS)

  2. 2

    What is the chemical name for TMS?

    Model answer

    Tetramethylsilane

  3. 3

    What is the molecular formula of TMS?

    Model answer

    Si(CH₃)₄ or C₄H₁₂Si

  4. 4

    Why does TMS produce a single sharp peak in both ¹H NMR and ¹³C NMR spectra?

    Model answer

    All twelve hydrogen atoms are in identical chemical environments, and all four carbon atoms are in identical chemical environments

  5. 5

    Why is the chemical shift of TMS defined as zero on the δ scale?

    Model answer

    TMS is used as the reference standard against which all other chemical shifts are measured

  6. 6

    Why is TMS chemically inert and unlikely to react with the sample being analysed?

    Model answer

    The silicon-carbon bonds are strong and TMS has no functional groups that would react with typical organic samples

Other ways to work this

The same content, four other ways.

What is inside Levo

Six ways to work the same material.

1Closed book
2Open book
3Closed book

The 3-step method, run for you

Answer cold, learn it, then prove it stuck. Levo tracks the jump between your first attempt and your last.

Atomic Structure
Amount of Substance
Bonding
Energetics and Thermodynamics

Cram a whole paper in one sitting

Sort every topic into what you know and what you do not, then drill only the weak ones.

A atom.
nitrogencarbonsulfur

Blank Blitz makes facts automatic

Rapid timed gap-fills on the terms and numbers you need to recall without thinking.

AOxidation is the loss of electrons.
BReduction is the gain of electrons.
CAn oxidising agent is an electron acceptor.

Build It gets the exam shape right

Assemble a full-mark answer from its marking points, in the order an examiner wants them.

The sum of all mole fractions equals 1.
TrueFalse

Test It catches misconceptions

Spot the fault in a statement. The traps are the mistakes students actually make.

721941163128510

Brain Breaks between sessions

Short focus games to reset attention, so the next set lands better than the last.

Every question in Organic Synthesis, NMR and Chromatography, on a schedule.

Attempt a question from memory, write the correct version, then attempt it again. Levo records the jump between your first attempt and your last, and brings each question back on the day you are due to forget it.

Or £46 a year, about £3.83 a month. Cancel anytime.