The formula for potassium sulfide is K2S
<span>Answer: a mixture.
</span><span>Justification:</span>
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</span><span>1) Pure substances have a definite chemical formula: the same kind of atoms with the same fixed ratios and chemical bonds. Therefore, the percents of each element do not varye.
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2) Elements and compounds are pure substaces. For example, Fe, Mg, Ti, are elements, and CO₂, CO, H₂CO₃ are compounds. Each of them will have always the same kind of atoms, in the same ratio and with the same chemcial bonds. Therefore the percents of the elements do not varye.
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<span>3) Mixtures are formed by the physical combination (not chemical bonds) of different elements or compounds in variable proportions. As indicated, this describes the material bronze, in virtue of the variation of its composition. Other examples of mixtures are solutions (like brines), air, ocean water, and milk: different brines, different oceans and different milk have different contents of elements or compounds.
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Hello, I don’t see the options
Once the substance stops dissolving, the system is at equlibrium with the water and the undissolved salt now, if it is in the process of dissolving because it is completely soluble but has not been able to completely dissolve, it is not at equilibrium