JAMB UTME - Chemistry - 1988

Crude copper can be purified by the electrolysis of CuSO4(aq) if?

A mixture of starch solution and potassium iodide was placed in a test tube. On adding dilute tetraoxosulphate (lV) acid and then K2Cr2O7 solutions, a blue-black colour was produced. In this reaction, the?

The thermal decomposition of copper (ll)trioxonitrate (V) yields copper (ll) oxide, oxygen and?

Carbon (ll) oxide may be collected as shown above because it

Which of the following acts as both a reducing and an oxidizing agent?

Given the reactions (i) Fe(s) + X(NO3)2(aq) → Fe(NO3) + X(s) (ii) H2(g) + XO → X + H2O(s); X is likely to be?

Suitable reagents for the laboratory preparation nitrogen are?

Which of the following substances is a basic salt?

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

Which of the following dilute solutions has the lowest pH value?

What are the possible oxidation numbers of an element if its atomic number is 17?

Answer Details

17 = 2, 8, 7

The IUPAC name for

Which of the following is used in fire extinguishers?

Methylethanoate reacts with ammonia to yield?

Which of the following physical properties decreases across the Periodic Table?

An eruption pollution an environment with gas suspected to be H2S, a poisonous gas. A residue team should spray the environment with?

One mole of propane is mixed with five moles of oxygen. The mixture is ignited and the propane burns completely. What is the volume of the products at s.t.p?(G.M.V = 22.4 dm3 mol-1)

Answer Details

C3H8 + 5O2 → 3CO2 + 4H2O
When the mixture is ignited CO2 is collected as product. From the equation 33 moles of CO2 is produced which equals 3 x 2.4 dm3 = 67.2 dm3 at S.T.P

Which of the following statements is NOT correct?

Answer Details

Increasing the pressure confines the gas molecules to a smaller space, thereby reducing the volume. Reducing the pressure the other way round increases the volume of a gas.

What volume of a 0.1 M H3PO4 will be required to neutralize 45.0 cm3 of a 0.2 M NaOH?

Chlorine is produced commercially by?

Which of the followingstatements is TRUE?

In the experiment above, ammonium chloride crystals deposit on the walls of the tube is as a result of

The formula of a compound formed in a reaction between a trivalent metal M and a tetravalent non-metal X is~?

Answer Details

M2+ + X-4 = M4X3

Which of the following reactions takes place in the cathode compartment during the electrolysis of copper (II) chloride solution?

Alkanoates are formed by the reaction of alkanoic acid with?

A metallic ion X2+ with an inert gas structure contains 18 electrons. How many protons are there in this ion?

2.25g of a sample of an oxide of copper on reduction gave 2.0g of copper. 2.50g of another oxide of copper on reduction also gave 2.0g of copper. These results are in accordance with the law of?

The energy changes accompanying the addition of an electron to a gaseous atom is called?

What process would coal undergo to give coal gas, coal tar, ammoniacal liquor and coke?

Which property of a reversible reaction is affected by a catalyst?

The molar ratio of oxygen to nitrogen in dissolved air is 2:1 whereas the ratio is 4:1 in atmospheric air because?

Answer Details

The ion that may be assumed to have negligible concentration in a sample of water that lathers readily with soap is?

When H2S gas is passed into a solution of iron (III) chloride, the colour changes from yellow to green. This is because?

A substance S is isomorphous with another substance R. When a tiny crystals of S is added into a supersaturated solution of R?

Detergents have the general formula?

Use the graph above to answer this question. The mass of a substance, M, liberated at an electrode during electrolysis is proportional to the quantity of electricity, Q passing through the electrolyte. This is represented graphically by.

In the experiment above, ammonium chloride crystals deposit on the walls of the tube is as a result of

Which of the following will produce the greatest increase in the rate of the chemical reaction represented by the equation Na2S2O3(aq) + 2HCl(aq) → 2NaCI(aq) + H2O(I) + SO2(g) + S(g)?

Which of the following compounds has the highest boiling point?

The four classes of hydrocarbons are?

The acidic hydrogen in the compound is the hydrogen attached to carbon number

Aluminium is extracted commercially from its ore by?

The diagram above shows the reaction path of an exothermic reaction. The heat of reaction is represented by

Which of the following in aqueous solution is neutral to litmus?

The forces holding naphthalene crystals together can be overcome when naphthalene is heated to a temperature of 354K resulting in the crystal to melting. These forces are known as?