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Read the descriptions below of two substances and an experiment on each. Decide whether the result of the experiment tells you the substance is a pure substance or a mixture, if you can .

Sample A is 100 ml of a clear liquid. The density of the liquid is measured, and turns out to be 0.77 g/ml. The liquid is then heated in a flask until boils. The vapor that rises off the boiling liquid is collected for 10 minutes and cooled until it condenses into a separate beaker. The density of the liquid that remains in the flask is then measured, and turns out to be 1.04 g/mL.
Sample B is 100 g of a coarse grey powder with a faint unpleasant smell. 15. g of the powder is put into a funnel lined with a sheet of thick paper, Distilled water is poured slowly over the powder. Most of the powder disappears, but of a gritty black sand-like material is left on the surface of the paper Pouring more water over the black material doesn't change how much of it there is pure substance
Is sample A made from a pure substance or a mixture? If the description of the substance and the outcome of the experiment isn't enough to decide, choose "can't decide. mixture (can't decide) pure substance mixture
Is sample B made from a pure substance or a mixture? If the description of the substance and the outcome of the experiment isn't enough to decide, choose "can't decide." can't decide)

1 Answer

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Answer:

Both sample A and B are mixtures .

Step-by-step explanation:

Sample A

The given sample has density of .77 g / ml and a component of sample that is separated from vaporization has different density of 1.04 g / mL . From this density it appears that it is water . So sample a appears to be a mixture of water and another matter having lesser density and it is water soluble .

Sample B

It is also a mixture . One component is soluble in water and the other black component is not soluble in water . The soluble component gets dissolved in water and get separated and filtered out . The insoluble part remains stuck to filter paper .

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