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Norma-Jean [14]
3 years ago
8

In NMR if a chemical shift(δ) is 211.5 ppm from the tetramethylsilane (TMS) standard and the spectrometer frequency is 556 MHz,

how many Hz from TMS is the signal at? Give at least three significant figures.
Chemistry
1 answer:
Vika [28.1K]3 years ago
6 0

Answer:

The answer is: 11759 Hz

Explanation:

Given: Chemical shift: δ = 211.5 ppm, Spectrometer frequency = 556 MHz = 556 × 10⁶ Hz

In NMR spectroscopy, the chemical shift (δ), expressed in ppm, of a given nucleus is given by the equation:

\delta (ppm) = \frac{Observed\,frequency (Hz)}{Frequency\,\, of\,\,the\,Spectrometer (MHz)} \times 10^{6}

\therefore Observed\,frequency (Hz)= \frac{\delta (ppm)\times Frequency\,\, of\,\,the\,Spectrometer (MHz)}{10^{6}}

Observed\,frequency= \frac{211.5 ppm \times 556 \times 10^{6} Hz}{10^{6}} = 11759 Hz

<u>Therefore, the signal is at 11759 Hz from the TMS.</u>

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To solve this problem we should know this formula:

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If the pressure keeps on constant, volume is modified directly proportional to absolute temperature. As T° has increased, the volume increased too

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Answer:

0%

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    2. One parent is homozygous dominant and the other is homozygous recessive.

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8 0
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