A rough & ready method involves memorising three numbers â 3, 5 and 8 â and the fact that 1 km in miles is approximately equal to the first of these numbers divided by the second, or alternatively the second divided by the third. That is: 1 km â 3/5 or 5/8 miles.
Ammonium chloride solutions with ammonia are used as buffer solutions. In paleontology, ammonium chloride vapor is deposited on fossils, where the substance forms a brilliant white, easily removed and fairly harmless and inert layer of tiny crystals.
Quaternary ammonium compounds are prepared by the alkylation of tertiary amines (which may be obtained by the EschweilerâClarke reaction) with a halocarbon. In older literature this is often called a Menshutkin reaction, however modern chemists usually refer to it simply as quaternization.