Answers section
Questions 2.5a
- What difference between sand and water (or the black solid used) does this separation rely on? ----
- Name the material used in this method to cause separation of the mixture ----
- Why is this material able to cause separation? -----------------------------
- Suggest a name for this method of separation. ------------------------
- What is the use of glass rod? ---------------------------------
- Name any five (5) other substances that flow like water. -----------------------
- Name two other binary mixtures which can be separated using this method. ---
- Why is this method not suitable for separating a solution of sodium chloride or other salts in water?
Answers to Questions 2.5a
- Water consists of lose tiny particles which can pass through the pores in a filter paper; sand does not.
- Filter paper.
- It has small holes which allow liquids to pass through but not solids.
- Filtration method.
- To prevent over-tilting of the beaker as this would large amount of sand to pour onto the filter funnel, slowing down the process and damaging the filter paper.
- Ethanol, methanol, propanone, petrol, kerosene, and other thin liquids.
- Water and iodine, water and sulphur, muddy water, mashed leaves/flower and water, ethanol and fermenting solids, water and flour, oil and metal or dust particle, sand and oil, (any liquid with any insoluble substance).
- The particles of both the solvent (water) and solute (salt) are small; so they both pass through the filter paper.