How does the presence of dust grains impact the measurable abundance of certain elements in the gas phase of dense clouds?

Answer

It locks up elements like iron, magnesium, and nickel, resulting in lower gas-phase measurements.

Dust acts as a sink for certain heavy elements, incorporating them into solid grains and thereby reducing the concentration of those elements detected spectroscopically in the surrounding gas.

How does the presence of dust grains impact the measurable abundance of certain elements in the gas phase of dense clouds?
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