The IR spectrum of a solid can be taken by dissolving it to create a solution. An appropriate solvent is because its IR stretches are

An appropriate solvent is carbon tetrachloride because its IR stretches are not visible in the infrared region.

Explanation:

Non-polar solvents don not show peaks at the IR frequency region because they do not have dipoles which would absorb the infrared light. This makes them suitable solvents in IR Spectroscopy.

Therefore non-polar solvents such as CCl4 or Carbon disulfide are appropriate for the IR spectrum. They also do not interfere with the halide disks used in the spectrometer, as a solvent like water would.

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the answer is b. dilution