UNIPORT Chemistry 2006/2007 Past Questions

Practice each question, then open it to see the full details.

Stainless steel is an alloy of

A.Carbon, Iron and lead
B.Carbon, Iron and Chromium
C.Carbon, Iron and Copper
D.Carbon, Iron and Silver
E.Carbon and Iron only

Crude petroleum usually seen on some Nigeria's creeks and water ways can be dispersed or removed by

A.heating the affected parts in order to boil off the petroleum
B.Mechanically stirring to dissolve the petroleum in water
C.Pouring organic solvents to dissolve the petroleum
D.Spraying the water with detergents
E.Cooling to freeze cut the petroleum

Solutions X, Y and Z have PH values of 3.0, 5.0 and 9.0 respectively. Which of the following statements is correct?

A.All the solutions are acidic
B.All solutions are basic
C.Y and Z are more acidic than water
D.Y is more acidic than X
E.Z is the least acidic

A molar solution of caustic soda is prepared by dissolving

A.40g NaOH in 100g of water
B.40g NaOH in 1000g
C.20g NaOH in 500g of solution
D.20g NaOh in 1000g of solution
E.20g NaOh in 80g of solution

Water is said to be hard if it

A.easily forms ice
B.has to be warmed before sodium chloride dissolves in it
C.Forms an insoluble scum with soap
D.contains nitrates
E.contains sodium ions

Chemical substances are mentioned as follows (I) sour taste (II) slippery to touch (III) yields alkaline gas with ammonium salts (Iv) has pH less than 7 (V) turns phenolphthalein pink. which of thee above are NOT typical properties of alkali?

A.(I), (IV) and (V)
B.(IV) and (V)
C.(I) and (IV)
D.(III) and (V)
E.(II), (III) and (V)

The movement of liquid molecules from the surface of the liquid into gaseous phase above it is known as

A.Brownian movement
B.Condensation
C.Evaporation
D.Liquefaction

Ammonia gas is normally dried with

A.Concentrated sulphuric acid
B.Quicklime
C.Anhydrous calcium chloride
D.Magnesium sulphate

oxygen demanding wastes are considered to be a water pollutant because they:

A.Deplete Oxygen which is necessary for the survival of aquatic organism
B.Increase oxygen which is necessary for the survival of aquatic organisms
C.Deplete other gaseous species which are necessary for the survival of aquatic organisms
D.Increase other gaseous species which are necessary for the survival of aquatic organisms

Mortar is NOT used for underwater construction because

A.It hardens by loss of water
B.its hardening does not depend upon evaporation
C.It requires concrete to harden
D.It will be washed away by the low of water