You have to dissolve the salt to separate liquid ( salt ) from solid ( sand ). In order to do this, you will have to filter the mixture to obtain the liquid ( salt ) as your filtrate and sand as your residue. When the liquid evaporates, only the water will evaporate as it contains only salt and water. Salt will remain to its original condition once evaporated.
Question 7 - B
Aluminium cannot be attracted by a magnet nor can it be magnetised. Steel can be attracted by a magnet but it takes a longer time. Iron is a soft metal ( easily magnetised metal ).
Question 8 - C
Distillation is used to separate liquids that are mixed together with different boiling points. The liquid that has the lowest boiling point will evaporate and become a gas and it is passed through a condenser to cool and condese into liquid form again so that it can be collected as a liquid in a container/flask.
Hope I have answered and explained well for you to understand. Hope you will excel at your studies! :)
