metaphor noun [C or U]. C2 an âexpression, often âfound in âliterature, that âdescribes a âperson or âobject by referring to something that is âconsidered to have âsimilar âcharacteristics to that âperson or âobject: The âmind is an âocean and the âcity is a âjungle are both metaphors.
A precipitate is an insoluble solid that emerges from a liquid solution. The emergence of the insoluble solid from solution is called precipitation. Often the precipitate emerges as a suspension.recipitates can form when two soluble salts react in solution to form one or more insoluble products-as discussed in the famous example below.
1 At equilibrium, the ion product = solubility product (K sp) and the solution is said to be saturated. 2  A precipitate will form when two solutions are mixed if the ion product is greater than the solubility product, ie, [M + ][A-sp.