The best way to obtain pure, solid household salt from a solid mixture of household salt and sand is to "add water, stir, filter and evaporate the filtrate".
<u>Option: C</u>
<u>Explanation:</u>
The salt and sand can be separated on the basis of solubility, as we know the salt is chemically known as sodium chloride, which have good solubility in water. The most general method is the mixture is taken into a flask or beaker and water is added with stirring, where salt get dissolved and sand remain as it is, because NaCl is capable enough to form hydrogen bonding with water, while sand have absence of such property. Then this solution containing insoluble sand is filtered by using filter paper. The sand is received in filter paper while filtrate in beaker is evaporated by boiling it in order to receive salt as residue.
Ch4 is the lowest boiling point
Because the catalyst is not really part of the reaction. it is something that speed up a reaction by lowering the energy need for the reaction to take place. however, in the end the catalyst is brought back to its initial state. that's why it is long lasting
A homogeneous mixture is a mixture that is mixed so well together that you cannot see the different components that make up the mixture as the ingredients will not separate out, even over time.
