JAMB UTME - Chemistry - 1986

Which of these represents a redox reaction?

Antwortdetails

In the course of an experiment, two gases X and Y were produced. X turned wet lead ethanoate to black and Y bleached moist litmus paper. What are the element(s) in each of the gases X and Y respectively?

Antwortdetails

How much of magnesium is required to react with 260cm3 of 0.5 M HCl? [Mg = 24]

Antwortdetails

The relationship between the velocity (U) of gas molecules and their relative molecular mass (M) is shown by the equation

Antwortdetails

The relationship between (U) of a gas molecule and the relative molecular mass is $\overline{U}$ = ($\frac{k}{m}$)${}^{\frac{1}{2}}$

or $\overline{U}$ = $\sqrt{k}m$

The movement of liquid molecules from the surface of the liquid to the gaseous phase above it is known as?

Antwortdetails

Which of the following is used as an 'anti-knock' in automobile engines?

Antwortdetails

Which of the following are made by the process of polymerization?

Antwortdetails

A white solid suspected to be lead trioxonitrate (V) zinc trioxocarbonate (IV) or calcium trioxocabonate (IV) was heated strongly. Its residue which was yellow when hot and white when cold is?

Antwortdetails

An element with atomic number twelve is likely to be

Antwortdetails

Which of the following salts when dissolved in water will NOT give the corresponding pH value?

Antwortdetails

Which of the following sulphides is insoluble in dilute HCl?

Antwortdetails

10cm3 of hydrogen fluoride gas react with 5cm3 of dinitrogen difluoride gas (N2F2) to form 103 of a single gas. Which of the following is the most likely equation of the reaction?

Antwortdetails

Which of the following is NOT correct test for the named organic compound in each case?

Antwortdetails

Starch can be converted to ethyl alcohol by?

Antwortdetails

The number of atoms of chlorine present in 5.85g of NaCl is [Avogaro's Number = 6.02 x 1023]

Antwortdetails

The number of atoms of chloride present in 5.85g of NaCl is 5.85 x 6.0 x 1023

= 6.02 x 1022

What reaction takes place when palm-oil is added to potash and foam are observed?

Antwortdetails

Which of the following compounds is NOT formed by the action of chlorine on methane?

Antwortdetails

Use the options above to answer this question. Which is the structural formula for pent-2-enoic acid?

Antwortdetails

How will a metal X, which reacts explosively with air and with dilute acids be best extracted from its ores?

Antwortdetails

Which of the following metals does NOT form a stable trioxocarbonate (IV)?

Antwortdetails

The exhaust fumes from a garage in a place that uses petrol of high sulphur content are bound to contain?

Antwortdetails

Which of the following compounds would give lilac flame coloration and a white precipitate with acidified barium chloride solution?

Antwortdetails

What mass of a divalent metal M (atomic mass = 40) would react with excess hydrogen gas measured at S.T.P?

Antwortdetails

Oxygen-demanding waste are considered to be a water pollutant because they?

Antwortdetails

In the electrolysis of aqueous solution of K2SO 4 in the above cell, which species migrate to the anode?

Antwortdetails

The general formula of an alkyl halide (where X represents the halide) is?

Antwortdetails

In the solubility curve above, water at 98oC is saturated with KCL and KCIO3 What is the percentage of KCL impurity in the crystals formed when the solution is cooled to 30 oC?

Antwortdetails

The reaction Mg + H2O → MgO + H2 takes place only in the presence of?

Antwortdetails

A substance Z reacts with NaOH to give salt and water only. When Z is treated with dilute HCl, a gas is evolved which gives a yellow suspension on passing into concentrated H2SO4. Substance Z is?

Antwortdetails

Which of the following groups of physical properties increases from left to right of the periodic table? i. Ionization energy ii. Atomic radius iii. Electronegativity iv. Electro affinity

Antwortdetails

Which of the following substances is a mixture?

Antwortdetails

Which of the following does NOT contain aluminium as component?

Antwortdetails

The approximate volume of air containing 10cm3 of oxygen is?

Antwortdetails

Volume of air containing 10 cm O2 is
(100 x 10)/(20) = 50cm3

How many coulombs of electricity are passed through a solution in which 6.5 amperes are allowed to run for 1.0 hour?

Antwortdetails

Which of the following will react further with oxygen to form higher oxide?

Antwortdetails

The iron (III) oxide impurity in bauxite can be removed by?

Antwortdetails

Which of the following solutions will conduct the least amount of electricity?

Antwortdetails

Ammonia gas is normally dried with?

Antwortdetails

Which of the following is an acidic salt?

Antwortdetails

When steam is passed through red hot carbon, which of the following are produced?

Antwortdetails

When chlorine is passed into water and subsequently exposed to sunlight, the gas evolved is?

Antwortdetails

20 cm3 of 1.0 molar NH4OH solution when neutralized with 20.05cm3 of 0.1 molar HCl liberated -102 joules of heat. Calculate the heat of neutralization of NH4OH?

Antwortdetails

NH4OH = 20cm of 0.1 m
NH4 + HCl → NH4Cl = H2O
Heat of Neutralization of NH4OH
= $\frac{-102}{2}$ = -51.0 KJ mole-1

When ethanol is heated with excess concentrated sulphuric acid, the ethanol is?

Antwortdetails

What are the values of x, y and z respectively in the equation: xCu + yHNO3 ? xCu(NO3)2 + 4H2O + zNO?

Antwortdetails

What is the consequences of increasing pressure on the equilibrium reaction ZnO(s) + H2(g) Zn(s) + H2O(I)?

Antwortdetails

When 50cm3 of a saturated solution of sugar (molar mass 342.0g) at 40oC was evaporated to dryness, 34.2g of dry solid was obtained. The solubility of sugar at 40oC is

Antwortdetails

The tabulated results below were obtained by titration 10.0 cm3 of water with soup. The titration was repeated with the same sample of water after boiling. The ratio of permanent to temporary hardness is

Antwortdetails

The ratio of permanent to temporary hardness will be 20:(20 - 15)

= 20:5

= 4:1