WAEC SSCE - Chemistry - 2023 (Objective)

An element X has two isotopes, \(^{65}X_{30}\) and \(^{66}X_{30}\) with relative abundance of 60 % and 40% respectively. The relative atomic mass of X is

The primary component of natural gas

Which of the elements in the table below would react more readily with chlorine?
      

Which of the following statements about the collision theory is correct?

Which of the following statements is correct?

Positive ions in a sea of electrons are found in

A consequence of global warming is

Which of the following laws or theory cannot be explained by the application of the kinetic theory of gases?

Which of the following elements has its valence electrons in the s-orbital?

Petrochemistry is an example of

Consider the following reaction equation:
\(2SO_3(g) → 2SO_2(g) + O_2\)(g)
∆H = +198 kJ/mol
Which of the following statements about the reaction is correct?

Which of the following equations does not illustrate correctly one of the reactions of chlorine?

Arrange the following compounds in decreasing order of their boiling points: \(NH_3\), HF, \(SiH_4\), \(CH_4\)

Going down group II in the periodic table normally

Determine the volume of 0.100 mol of HCl in \(0.250 mol dm^3\) of solution.

If \(100^3\) of a saturated solution of sodium tetraoxosulphate (VI) at 30° C contains 10.5 g of the salt, what would be its solubility at this temperature? [(\(Na_2SO_4\) = 142]

The following steps are scientific methods except

A mixture containing two salts of different solubility can be separated by

Which of the following equimolar solutions has the highest conductivity?

The reduction half equation of the following reaction is:
\(Zn_{(s)} + CuSO_{4(aq)} → ZnSO_{4(aq)} + Cu_{(s)}\)

Which of the following gases has the lowest rate of diffusion?
[H=1.0, C=12.0, N = 14.0, O= 16.0]

The gas that is less dense than air is

The separation technique that is suitable for separating iodine from tetrachloromethane is

Copper (II) ions are able to participate in co-ordinate covalent bonding because they

Carbon is deposited in the exhaust pipes of cars because of

The molecule that has a non-polar covalent bond is

An example of a crystalline substance that does not possess water of crystallization is

The periodic property that is used to determine whether a covalent molecule is polar or not is

Isoelectronic species have the same number of

How many moles are there in 3.0 g of \(O_2\)? [O = 16.0]

How many grammes of NaOH(s) would be needed to produce 100.0 cm3 of a 0.20 mol dm-3 NaOH, (aq)? [NaOH = 40.0]

The relative molar mass of a gaseous hydrocarbon is 30. Determine its vapour density.

What takes place at the cathode during electrolysis?

The vapour density of an organic compound with the molecular formula \(C_2H_4O_2\), is
[H=1.0, C=12.0, O= 16.0]

The salt solution formed firm a reaction between ethanoic acid and sodium hydroxide solution would be

A compound that could be dried by using conc. tetraoxosulphate (VI) acid and not by calcium oxide is likely to be

Which of the following properties does not give evidence of the kinetic theory of matter?

The pair of compounds that belongs to the same homologous series is

Alkenes can be manufactured by

How many moles of copper would be deposited by passing 1 Faraday of electricity through a \(CuCl_2\) solution?

The formation of a bond between hydrogen and a highly electronegative atom results in

Which of the following reactions represents the hydrolysis of an alkanoate?

How many unpaired electrons are present in \(_{26}Fe^{3+}\)?

Thermal cracking of alkanes usually

Which of the statements about gases is not correct?

Why are \(H_2SO_4\) and \(CaCl_2\), not suitable for drying ammonia gas? They

Dilute trioxonitrate (V) acid does not produce hydrogen when it reacts with metals because

The following statements are correct except

The best indicator to use for the titration of ethanoic acid with sodium hydroxide is

Species that occur in a reaction pathway but not in the overall reaction are known as