OAU Chemistry 2011/2012 Past Questions

Whose experiment showed that the atom has a tiny positively charged nucleus?

Which of the quantum number divides shells into orbitals?

Which of these statements is / are correct of a proton? : i. The mass of a proton is one-twelfth the molar mass of carbon ii. The mass of a proton is 1840 times the mass of an electron iii. The mass of a proton is 1.0008g.

Candidate devised the following for the separation of the components of some mixtures.: i. components of ink; principles involved is chromatography ii. Components of water and kerosene principle involved is separating funnel iii. Components of iodine and sodium chloride, principles involved is sublimation. In which of the above is the principle used correct?

Which of the following procedures will separate a mixture of sand sodium chloride and iodine into its components?

The type of bonds in ammonium chloride are

Which of the following types of bonding does not produce a compound?

The combining powers of HCO₃, O, Na, CI, respectively are

What is the chemical formula of the compound containing: 6.02 x 10²³ atoms of hydrogen, 35g of chlorine, and 4 moles of oxygen atoms?

200cm³ of hydrogen were collected over water at 30°C and 740mm of Hg. Calculate the volume of the gas at s.t.p. If the vapour pressure of water at the temperature of the experiment is 14mm of Hg.

A given mass of gas occupies a certain volume at 300K. AT what temperature will its volume be double?

The basic assumption in the kinetic theory of gas that: "forces of attraction and repulsion between gaseous molecules are negligible" implies that:

Which of the following is true of a sample of hydrogen gas whose mass is 4.00g under a pressure or 2atm and a temperature of 27°C? (H = 1, R = 0.082 lit atm. mol^-1 deg^-1)

The following are chemical entities identifiable during qualitative analysis. i. sO4^2- ii. H3O iii. NH4 iv. 0H. Which of them can be detected-by litmus paper?

I. NaHCO₃ II, NaHSO₄ III. NaCI. Which of these will dissolve in water to give alkaline solution'?

Burning of 0.46g of ethanol produced heat that raised the temperature of 100g of water by 30°C. Calculate the heat of combustion of ethanol, C₂H₅OH. (C = 12; H = 1; 0 = 16)

When chlorine is bubbled into potassium iodine solution:

PCl_5(g) ⥨ PCl_3(g) + Cl_2(g)In the reaction above, an increase in pressure will

A saturated solution of silver trioxocarbonate (IV), was found to have concentration of $1.30 x 10^5 mol dm^-3$. The solubility product of trioxocarbonate (IV) is

A Zinc half-cell is connected to an iron half-cell through a salt bridge and both are also connected through a copper wire. At which electrode is reduction taking place and which electrode is positively charged?

Which of the following is the difference between an electrolytic cell X and electrochemical cell Y:

What mass of bromine will saturate completely 6.8g of 3-methybut- 1 -yne (H = 1; C = 12; Br = 80)

100cm³ of oxygen and 10cm³ of butane measured at room temperature and pressure were mixed and exploded. Determine the volume of the mixture when brought back to the original conditions of measurements.

Sulphur

Which of the following combination of reagents will reacts to give chlorine gas?