Purity and separating mixtures

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Question 8

Medium

A student has a mixture containing insoluble silicon dioxide (silica) powder, water, and dissolved nickel(II) chloride.

Describe a method the student could use to separate and collect pure, dry samples of:

silicon dioxide
water
nickel(II) chloride crystals

[3]

The student has a sample of iron(III) chloride, $FeCl3\text{FeCl}_3$ .

Calculate the relative formula mass ( $M_r$ ) of this sample of iron(III) chloride, where all of the chlorine atoms are the isotope chlorine-37 ( $1737Cl^{37}_{17}\text{Cl}$ ).

Relative atomic mass ( $A_r$ ): $Fe=55.8\text{Fe} = 55.8$ .

[2]

The student wants to separate different plant pigments in a mixture using paper chromatography.

The spot containing beta-carotene does not move from the start line on the chromatogram.

State one change the student should make so that the beta-carotene can be separated.

[1]

Explain why calcium oxide, $CaO\text{CaO}$ , has a high melting point.

[3]

Purity and separating mixtures

Question 8

Purity and separating mixtures Questions

Purity and separating mixtures

Question 8

Purity and separating mixtures Questions