GTZ (India) Junior Executive Chemist Interview Questions and Answers

A buffer solution is a solution that resists changes in pH when small amounts of acid or base are added.

• Consists of a weak acid and its conjugate base, or a weak base and its conjugate acid

• Maintains a relatively constant pH

• Used in various chemical and biological applications

• Examples include acetic acid/sodium acetate buffer and phosphate buffer

The 2nd law of thermodynamics states that the total entropy of an isolated system can never decrease over time.

• Entropy always tends to increase in a closed system

• Heat cannot spontaneously flow from a colder location to a hotter location

• The law explains why energy tends to disperse and systems tend towards disorder

• Examples include a cup of hot coffee cooling down in a room, or a car engine losing energy as heat