When ammonium chloride is dissolved in water in a test tube, the tube feels colder showing that

A. the solution is unsaturated

B. sublimation has ocurred

C. ammonia gas is evolved

D. the process is endothermic

E. condensation has occurred

Zinc displaces copper from an aqueous solution of copper (ll) salt because

A. copper is a transition element

B. copper is a moderately reactive metal

C. Zinc and copper have reducing prperties

D. zinc is more reactive than copper

E. zinc reacts with both acids and alkalis

The alloy used for metal work and plumbing contains

A. lead and tin

B. iron and carbon

C. copper and tin

D. aluminium and copper

E. lead and antimony