Which metal is protected by the layer of its own oxide ?

A. Iron
B. Silver
C. Calcium
D. Aluminium

Aluminium as a material of construction suffers from the disadvantage of__________________?

A. Very high cost
B. Rather low tensile strength
C. Very low strength to weight ratio
D. Scarce availability

Nickel made/clad equipments are suitable for handling________________?

A. Ammonia (both aqueous & anhydrous)
B. Fruit juices, milk & its products and caustic soda solution
C. Nitric acid & hydrochloric acid (concentrated)
D. Sulphuric acid (concentrated)

Steel tower used for the storage of oleum________________?

A. Is lined with lead
B. Need not be lined
C. Is lined with rubber
D. Is lined with acid-proof bricks

A suitable material of construction to use with fuming sulphuric acid is_________________?

A. Carbon steel
B. Stainless steel type 304
C. Nickel
D. Monel

Most suitable material of construction for the storage of concentrated nitric acid is__________________?

A. Cast iron
B. Monel
C. Karbate
D. Aluminium or chromium alloys (Cr > 18% for cold acid)

Which of the following would not be a suitable material of construction for handling aqueous hydrofluoric acid (HF) at 100°C ?

A. Monel
B. Stainless steel
C. Graphite
D. Kel-F and Teflon

The formation of oxide film on a metal due to atmospheric exposure reduces its____________?

A. Toughness
B. Stiffness
C. Creep limit
D. All A., B. & C.

An elastic behaviour of materials is expressed in terms of_______________?

A. Hysteresis loop area
B. Stress-strain curve
C. Relaxation time
D. None of these

Fatigue strength of a material increases by_____________________?

A. Having notches in the specimen
B. Rise in temperature
C. Under stressing the specimen
D. Having scratches on the surface