A cup of coffee is made in the morning by pouring water ov er ground up coffee beans in a piece of paper and by collecting the brown liquid that comes through. Which techniques used

Filtration technique

Explanation:

The technique used here is called filtration.

Filtration,is a physical separation process that separates a mixture of an insoluble solid from a liquid ( acting as the solvent) by the use of a filter barrier that allows only the fluid to pass through.

In the case from the question,

As water is poured over the ground coffee, it forms a mixture of which the insoluble solid is the coffee grounds, the water is the liquid  and the filter barrier is the piece of paper  which allows only the brown  liquid coffee to pass through as the filtrate.

frequency, z, and the collision density, z, in carbon dioxide (co2), r 180 pm at 30 °c and 120 kpa