The phenomenon of existence of an element in more than one form in the same physical state is called _____.

1. 1. dimorphism
   2. isomorphism
   3. isomerism
   4. allotropy

The phenomenon in which a chemical reaction is accelerated or retarded by the mere presence of a substance which remains unchanged at the end of the reaction is called _____.

1. 1. catabolism
   2. cataclysm
   3. catalysis
   4. cataphoresis

Which of the following statements is true about reduction?

1. 1. Process involving addition of Oxygen
   2. Process involving removal of electronegative radical
   3. Process involving addition of electropositive radical
   4. Process involving addition of hydrogen

The conversion of a solid directly into vapour and its subsequent condensation without melting is called _____.

1. 1. deliquescence
   2. evaporation
   3. desiccation
   4. sublimation

Atoms of an element having the same atomic number but different atomic weights are called _____.

1. 1. cathode
   2. iron
   3. laser
   4. isotopes

Pyrolusite is the _____.

1. 1. ore of copper
   2. ore of lead
   3. ore of manganese
   4. ore of potassium

The atomic state of an element as a result of chemical reaction in which it is more active than in ordinary molecular state is called _____.

1. 1. critical state
   2. nacent state
   3. nuclear state
   4. neutral state

A property of some substances of absorbing moisture from the air on exposure is called _____.

1. 1. desiccation
   2. dimorphism
   3. efflorescence
   4. deliquescence

The substance which acts both as a base and as an acid under different circumstances is called _____.

1. 1. amorphous
   2. halogen
   3. amphoteric
   4. cation

A mixture of concentrated nitric and hydrochloric acids in the ration 1:3 is called _____.

1. 1. aquasol
   2. aqua regia
   3. aqua fortis
   4. aqua culture