1. What difference in physical properties enables the separation of mixtures by (a) simple distillation (b) paper chromatography (e) fractional distillation
2. (a) What is water of crystallization? (b) Differentiate between hydrous and anhydrous salis (c) State one advantage and one disadvantage of
evaporation by direct heating as compared to evaporation using a water bath or sand bath. (d) state two differences between distillation and evaporation.

Select the atomic models that belong to the same element

One way in which the useful metal copper is produced is by dissolving the mineral azurite, which contains copper(ii) carbonate, in concentrated sulfuric acid. the sulfuric acid reacts with the copper(ii) carbonate to produce a blue solution of copper(ii) sulfate. scrap iron is then added to this solution, and pure copper metal precipitates out because of the following chemical reaction: (s) (aq) (s) (aq) suppose an industrial quality-control chemist analyzes a sample from a copper processing plant in the following way. he adds powdered iron to a copper(ii) sulfate sample from the plant until no more copper will precipitate. he then washes, dries, and weighs the precipitate, and finds that it has a mass of .

What are some natural measures of time