IR sample preparation for solid samples What is

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IR sample preparation for solid samples

IR sample preparation for solid samples

What is a mull? a mull a suspension of solid sample in mineral oil

What is a mull? a mull a suspension of solid sample in mineral oil n It is used to make a thin-film cell from a solid sample n

Thin film IR cells Salt (Na. Cl) discs are used n To hold the

Thin film IR cells Salt (Na. Cl) discs are used n To hold the sample n So the holder won’t absorb infrared light n and only sample absorption is detected n

Sample preparation n so dry the sample well because water etches the IR discs

Sample preparation n so dry the sample well because water etches the IR discs and emulsifies with oil letting less light through

How do I make a mull? grind n the sample n to a smooth

How do I make a mull? grind n the sample n to a smooth n powder n add mineral oil n and mix it n well n

What should the mull be like? the mull n should look n and spread

What should the mull be like? the mull n should look n and spread n like soft butter n

use clean gloves to work with salt discs put on an extra pair of

use clean gloves to work with salt discs put on an extra pair of gloves n to protect cells n from anything aqueous on your regular gloves n

applying the mull n n n n use a rubber policeman to spread a

applying the mull n n n n use a rubber policeman to spread a thin layer on one disc lower the 2 nd disc on top of the 1 st and twist the discs to spread sample evenly

placing discs in cell holder use your finger n to make a platform n

placing discs in cell holder use your finger n to make a platform n in the cell holder n lower in n the Na. Cl discs n do not wedge them n

gently n place lid n on top n slide into position n in light

gently n place lid n on top n slide into position n in light beam n

close n sample n compartment n remove gloves n before using n keyboard n

close n sample n compartment n remove gloves n before using n keyboard n

to cleann discs add a few drops of chloroform n to each disc n

to cleann discs add a few drops of chloroform n to each disc n rub gently n to clean off n all traces of sample n n …

Keep discs dry n n replace in desiccator after cleaning …

Keep discs dry n n replace in desiccator after cleaning …