JAMB UTME - Chemistry - 1978

You are provided with five gas jars containing SO₂, CO₂, H₂, CO and NO respectively. Select a test from A to E which will identify ANY ONE of the gases completely

Détails de la réponse

Which of the following metals cannot replace hydrogen from water or steam?

Détails de la réponse

Five compounds R,T,W,X and Y form the following compounds: a basic hydride R.H, an acidic hydride YH, atmospheric oxide W₂O₃, XO₂. which of the elements is an alkali

Détails de la réponse

When sodium chloride and metallic sodium are each dissolved in water

Détails de la réponse

The normal boiling point of a liquid is defined as

Détails de la réponse

The oxidation state of chlorine in potassium chlorate is

Détails de la réponse

When ammonia and hydrogen ion bond together to form ammonium ion, the bond formed is called

Détails de la réponse

A solid X when heated gives off a brown gas. If X is soluble in excess sodium hydroxide solution but insoluble in excess ammonium hydroxide solution, then X is

Détails de la réponse

Three solutions contain carbonate, sulphate and sulphide ions respectively. One test that will identify just ONE of them completely is by addition to each of them of

Détails de la réponse

During the electrolysis of copper II sulphate between platinum electrodes, if litmus solution is added to the anode compartment,

Détails de la réponse

Hypochlorous acid is used as a bleach because

Détails de la réponse

By means of filtration, one component can be obtained pure from an aqueous mixture of sodium chloride and

Détails de la réponse

Which of the following gases may not be dried with concentrated sulphuric acid?

Détails de la réponse

An experiment test of the Law of conservation of Mass is illustrated in the diagram. In practice, the flask is weighed before and after reaction between solutions X and Y. Which of the following pairs of solutions will be unsuitable for the experiments

Détails de la réponse

The reaction between an organic acid and an alcohol in the presence of an acid catalyst is known as;

Détails de la réponse

The most common type of chemical reaction which alkanes undergo is

Détails de la réponse

A gas jar was inverted over burning yellow phosphorus floating over water in a beaker. After burning, the water level was found to rise in the gas jar. The water level rises because

Détails de la réponse

The periodic classification of elements is an arrangement of the elements in order of their

Détails de la réponse

Elements P, Q, R, S have 6, 11, 15, 17 electrons respectively, therefore,

Détails de la réponse

Zinc Oxide is a

Détails de la réponse

A small quantity of solid ammonium chloride (NH₄Cl) was heated gently in a test tube, the solid gradually disappears to produce two gases. Later, a white cloudy deposit was observed on the cooler part of the test tube. The ammonium chloride is said to have undergone

Détails de la réponse

Two gas cylinders contain ethylene (ethene) and acetylene respectively. One test which can be used to distinguish between them is by

Détails de la réponse

Which of the following compounds will form a solution if exposed to air?

Détails de la réponse

Which of the following is not a member of the homologous series of the paraffins (alkanes)?

Détails de la réponse

The IUPAC names of the compounds CH3COOH and CH2=CH2 are respectively;

Détails de la réponse

The IUPAC names of the compounds CH3COOH and CH2=CH2 are respectively acetic acid and ethene. Acetic acid is a carboxylic acid with the formula CH3COOH, while ethene is an unsaturated hydrocarbon with the formula CH2=CH2. The IUPAC naming system is a set of rules used to give unique names to organic compounds based on their molecular structure. In this case, the IUPAC name of CH3COOH is derived from the parent alkane, which is methane (CH4). Replacing one hydrogen atom in methane with a methyl group (CH3) results in the parent chain for acetic acid, which is ethane (C2H6). The carboxyl group (-COOH) attached to the second carbon atom in the chain gives the compound its name, ethanoic acid. Similarly, the IUPAC name of CH2=CH2 is ethene, which is derived from the parent alkane, ethane, by removing one hydrogen atom from each of the two carbon atoms that form a double bond.

When each of the nitrates of Potassium, Magnesium and iron is heated,

Détails de la réponse

The pH of four solutions W, X, Y, Z are 4, 6, 8, 10 respectively, therefore

Détails de la réponse

Consider the following equation H₂O + 2Fe²⁺ + Cl₂ ↔ 2Fe³⁺ + 2Cl^- + H₂O. The only ion which behaves as an oxidising agent is

Détails de la réponse

Which of the following reactions does not take place in the smelting of iron in a blast furnace?

Détails de la réponse

When large hydrocarbon molecules are heated at high temperature in the presence of a catalyst to give smaller molecules, the process is known as

Détails de la réponse

Which of the five atoms can be described by the following properties: Relative atomic mass is greater than 30 but less than 40, it has odd atomic number and forms a unipositive ion in solution?

Détails de la réponse

Consider the following exothermic reaction
2SO_2(g) + O_2(g) ↔ 2SO_3(g)
If the temperature of the reaction is reduced from 800°C to 500°C, an no other change takes place, then

Détails de la réponse

Which of the following substances would you see as an indicator in the titration of sodium carbonate solution against hydrochloric acid (complete neutralisation)?

Détails de la réponse

If excess zinc is added to a bluish green solution of copper (II) sulphate, and the excess zinc filtered off after completion of reaction, a colourless solution is obtained because

Détails de la réponse

An element X forms the following compounds with chlorine; XCl₄, XCl₃, XCl₂. This illustrates the

Détails de la réponse

The size (diameter) of five elements are in the order R < T < W < X < Y, Y being the largest. If each atom has an electron situated on its circumference, and neglecting other factors, which of the atoms will lose its electron most reluctantly?

Détails de la réponse

If 30cm³ of oxygen diffuses through a porous pot in 7 seconds, how long will it take 60cm³ of chlorine to diffuse through the same pot, if the vapour densities of oxygen and chlorine are 16 and 36 respectively?

Détails de la réponse

A sample of hard water contains some calcium sulphate and calcium hydrogen carbonate. The total hardness may therefore be removed by

Détails de la réponse

Consider the solubility curves of three salts X, Y and Z given in the diagram. If each solution of the salt contains 200 g, and is heated to 100^oC, which solution or solutions will deposit 100 g of the solute when suddenly cooled to 0^oC?

Détails de la réponse

In the reaction between sodium hydroxide and sulphuric acid solutions, what volume of 0.5 molar sodium hydroxide would exactly neutralise 10cm3 of 1.25 molar sulphuric acid?

Détails de la réponse

Brass and bronze are both metallic alloys. Which of the following constituents is common to both alloys?

Détails de la réponse

Which of the following changes is physical?

Détails de la réponse

If hydrogen sulphide gas is passed into a solution of a pure iron chloride, a yellow deposit appears. If the deposit is filtered, a pale green solution is left behind. The pale green solution is

Détails de la réponse

An example of an alcohol is

Détails de la réponse

The nucleus of an atom contains

Détails de la réponse

When heat is absorbed during a chemical reaction, the reaction is said to be

Détails de la réponse

In titration involving sodium hydroxide and dilute hydrochloric acid, where would you place the base?

Détails de la réponse

When air which contains the gases Oxygen, nitrogen, carbondioxide, water vapour and the rare gases, is passed through alkaline pyrogallol and then over quicklime, the only gases left are;

Détails de la réponse