Sand, coffee grains and undissolved sugar all in water can be separated by a filter.
Usually by a combination of air jets and filter screens.
For example salts can be separated by crystallization.
Nitrogen
An element cannot be separated into simpler substances by chemical means.
A mixture of sand and salt can be separated through filtration because sand is insoluble in water while salt is soluble. When water is added to the mixture, the salt dissolves, creating a saltwater solution, while the sand remains as a solid. By pouring the mixture through a filter, the sand is trapped in the filter paper, and the saltwater passes through, allowing for the separation of the two substances.
Usually by a combination of air jets and filter screens.
Compound substances.
filtrate
chlorine is added to the filter beds
milk , separating colloids and organic substances
'separated three substances' is past tense.
For example salts can be separated by crystallization.
Nitrogen
An element cannot be separated into simpler substances by chemical means.
Substances can be separated through various methods such as filtration, distillation, evaporation, chromatography, and centrifugation. These techniques take advantage of the different physical and chemical properties of the substances to isolate them from each other.
Sodium can be separated into simpler substances only by chemical means. Water, salt, and gold are pure substances that cannot be separated into simpler substances by chemical means.
Sometimes is possible, depending on the type of the coloid; for example aerosols.