Crystallisation is based on the principles of solubility - compounds tend to be more stable in hot liquids than they are in cold liquids.

Out of all the actinides, thorium and uranium occur naturally in substantial, primordial quantities and small amounts of persisting natural plutonium have also been identified. The radioactive decay of uranium produces transient amounts of actinium and protactinium. The atoms of neptunium, americium, curium, berkelium and californium are occasionally produced from transmutation reactions in uranium ores. The other actinides are purely synthetic elements.

1,2-dichloroethylene (Cl)HC=CH(Cl) shows cis-trans isomerism whereas 2-hydroxy propanoic acid (CH3CH(OH)COOH) shows optical activity.

During fermentation of starch, it is first hydrolyzed to maltose by the action of the enzyme diastase.

The enzyme diastase is obtained from germinated barley seeds. Maltose is converted to glucose by the enzyme maltase. Glucose is converted to ethanol by another enzyme, zymase.

The lanthanide series comprises the fifteen metallic chemical elements with atomic numbers 57 through 71, from lanthanum through lutetium. These fifteen elements, along with the chemically similar elements scandium and yttrium, are often collectively known as the rare earth elements.

2,3,4-trichloropentane has 3 asymmetric carbon atoms.

Alkali metals are electropositive and have a tendency to lose electrons. On moving down the group, the ionisation energy decreases and metallic character increases.

Halogens react by accepting the electrons. On moving down the group, the tendency to accept an electron decreases due to decrease in electronegativity. Therefore, the reactivity decreases down the group.

Magnesite = MgCO₃

Dolomite = CaMg(CO₃)₂

Gypsum = CaSO₄·2H₂O

Carnallite = KMgCl₃·6(H₂O)

Besides diphenyl benzidine, all other chemicals can be used to identify nickel ion.

Propyne and propane both are unsaturated compounds and give the tests of unsaturation. Both will react with conc. H₂SO₄, decolourise Br₂ in CCl₄ and il. KMnO₄ solution. Only propyne (which is an alkyne) will give a white precipitate with ammoniacal AgNO₃.