ABU Chemistry 2012/2013 Past Questions

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

The separation of oil and water with different boiling points can be achieved by

A.Fractional distillation
B.decantation
C.evaporation
D.using a separating funnel

Calculate the minimum volume of oxygen that is required for the complete combustion of a mixture of 20cm³ of CO and 25cm³ of hydrogen.

A.45cm³
B.22.5cm³
C.20cm³
D.10cm³

An increase in temperature causes an increase in the pressure of a gas because there is an increase in the

A.Average velocity of the gas molecules
B.number of collisions between the gas molecules
C.density of the gas molecules
D.free mean path between each molecule and the other

A liquid begins to boil when

A.Its vapour pressure is equal to the vapour pressure of its solid at a given temperature
B.molecules start escaping from the surface
C.its vapour pressure equals the atmospheric pressure
D.its volume is slightly increased

If the relative rate of diffusion of a gas is 0.25 and that of Cl under the same condition is 0.20. calculate the relative molecular mass of the gas.

A.22.7
B.45.4
C.88.1
D.90.8

The following molecules contain hydrogen bonding EXCEPT

A.ammonia
B.ethanoic acid
C.hydrogen flourine
D.water

If 20cm³ of distilled water is added to 80cm³ of 0.50mol/dm³ HCl solution, the new concentration of the acid is

A.0.10mol/dm³
B.0.20mol/dm³
C.0.40mol/dm³
D.2.00mol/dm³

What is H₂O₂ acting as in the equation? H₂O₂ + 2Fe²⁺← 2Fe³⁺

A.oxidizing agent
B.reducing agent
C.an acid
D.a base

A 12v battery supplying a current of 20A was used to melt 1.5kg of ice at )°C. Calculate the time required if the Latent heat of fusion of ice is 338 × 10J/kg

A.35.0min
B.35min
C.76min
D.21.0min