Asealed beaker of what you are told is aqueous nickel sulfide was given to you by the local chemist and you put it on the window sill. after a few days, you notice that the mixture is getting thick toward the bottom. what is the nature of the initial nickel sulfide mixture, assuming that the temperature on the sill remained approximately constant?

The nature of the initial nickel sulfide mixture : suspension

A pure substance can be an element or compound.

The element is a single substance that cannot be broken down anymore or the simplest substance.

While the compound is a pure substance that is formed from a combination of two or more elements through chemical reactions and has a constant chemical ratio.

A mixture is a combination of two or more single substances. The properties of the mixture component are not lost / unchanged as in compounds.

The mixture can be divided into a homogeneous mixture if the composition/ratio of each substance in the mixture is the same and heterogeneous mixture if the ratio of the composition of the substances is not the same (can be varied) in each place.

Mixtures can also be divided into solutions, suspensions, and colloids based mainly on the size of the particles

Homogeneous mixture = Solution

Heterogeneous mixture = suspension, and

The mixture is located between suspension and solution = Colloid

The solution is a mixture of two or more substances consisting of a solute and a solvent. The particle size of the solution is very small, less than 1 nm, it cannot be distinguished between the solute and its solvent medium. Substances in a solution cannot be separated through filtering.

The solution has the same composition in each of its parts.

Suspensions are rough mixes and are heterogeneous. Particle size more than 100 nm.

The mixture is a murky solution, but it gradually separates due to the influence of gravity (undergoes precipitation). Suspension can be separated by filtering.

Colloids are mixtures of dispersed particles and dispersing particles. The size of colloidal particles lies between 1 nm - 100 nm

colloid mixtures cannot be separated through ordinary filtering, but rather with ultrafilters.

Aqueous nickel sulfide (NiS) has been deposited after being placed several days, so it can be classified into a mixture of suspensions

A heterogeneous mixture

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a homogeneous mixture

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an example of a physical change

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