When items of jewellery made of metals such as copper or nickel are placed in a solution having a salt of gold, a thin film of gold is deposited by

Combustion of a candle is

A. physical change

B. reduction reaction

C. endothermic reaction

D. exothermic reaction

Which law of the thermochemistry introduces the concept of entropy?

A. Second Law

B. Zeroth Law

C. Third Law

D. First Law

Which of the following is a closed system?

A. Jet engine

B. Tea placed in steel kettle

C. Pressure cooker

D. Rocket engine during propulsion

The entropy of perfectly crystalline solid at absolute zero is

A. positive

B. negative

C. Zero

D. not definite