UNIPORT Chemistry 2012/2013 Past Questions

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

Which of the following is/are water pollutants?

A.fertilizers
B.human waste
C.industrial waste
D.all of the above

Which of the following statements is correct of ΔH, the enthalpy of reaction?

A.the heat change accompanying a chemical reaction
B.negative fir exothermic reactions
C.positive for endothermic reactions
D.all of the above

A saturated solution of potassium chloride was prepared at x°C. if 30cm³ of the solution required 22.5cm³ of silver trioxonitrate(v) solution containing 34g in 100cm³ solution for complete precipitation, calculate the solubility of potassium chloride at x°C in mol/dm³.[take KCL = 74.5, AgNO₃ = 120]

A.1.5mol/dm³
B.2.0mol/dm³
C.0.15mol/dm³
D.0.20mol/dm³

The general methods of preparing salts include
i. neutralization ii. Precipitation iii. Double decomposition

A.i & ii
B.iii & iv
C.i, ii, iii, iv, & v
D.i, ii, iii & iv

When a metal plate is placed in a solution containing its ions, some of thee metallic ions in solution will take up electrons from the metal plate and deposit themselves as neutral atoms on the plate. Which option favours the reaction

A.the electrode or metal plate becomes positively charged with respect to the solution/electrolyte
B.the electrode or metal plate becomes positively charged with respect to the solution/electrolyte
C.The electrode or metal plate has more electrons with respect to the solution/electrolyte
D.the electrode or metal plate becomes negatively charged with respect to the solution/electrolyte

How many isomers can be obtained from C₄H₁₀?

A.0
B.1
C.2
D.3

Who discovered the atom?

A.Rutherford
B.Dalton
C.Neils Bohr
D.Goldstein

25cm³ of a gas x contains z molecules at 15°C and 75mmHg. How many molecules will 25xm³ of another gas y contain at the same temperature and pressure?

A.2y
B.2z
C.z
D.y

The technique used for the separation of immiscible liquids is

A.distillation
B.chromatography
C.the use of separating funnel
D.fractional distillation

Which of the following denotes alpha particle?

A.¹₀n
B.⁴₂He
C.⁰_-le
D.⁹₄Be

The Shapes of CO₂, H₂O and CH₄ respectively are

A.bent, linear and tetrahedral
B.bent, tetrahedral and linear
C.linear, bent
D.tetrahedral
E.tetrahedral, linear and bent