NECO SSCE - Chemistry - 2001

An experiment to test the conductance of 0,1 M solutions of the substances listed below was perform.
I ammonia
II ammonium chloride
III ethanoic acid
IV sodium ethanoate
Which pair of substances show the least conductance?

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The use of sulphur to vulcanize rubber is mad to make it

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A gas X diffuse through porous partition at the rate of 3 cm₃ per second. Under the same condition hydrogen diffused at the rate of 15 cm₃ per second.

What is the 42. relative molecular mass of X.

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The decreasing order of the oxidising power of the halogens is

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Faraday s first law of electrolysis can be expressed mathematically as

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The alloy used for welding and plumbing contains

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NaCl(s) does NOT conduct electricity, but N(aq) does. This is because

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Which statement BEST describes the process of oxidation?

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Which element contains the greatest number of moles?

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Ethanol is a product of fermentation of simple sugars. Which method is used to separate ethanol from the other products?

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The oxidation number of X in \(XO_{4}^{3-}\) is

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The maximum number of electrons that can occupy the shell having a principal quantum number of 3 is

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Animal charcoal differs from wood charcoal in that it

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The best way to distinguish between Na₂CO₃and NaHCO₂ is by.

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The atomic number of iron is 56. The number of unpaired electrons in the Fe3+ ion is

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When an electric current is passed through a solution containing dilute tetraoxosulphate (Vi) acid, 190 cm³ of hydrogen gas is evolved. if the measurements were made at 26°C and 736 mmHg, what is the volume of hydrogen at s.t.p.?

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Which compound is a component of baking powder?

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Detergents are better than soaps for washing in hard water because

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To test for the presence of chloride ions in ion, correct sequence of reagents to use is

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The high boiling point of hydrogen fluoride can be explained in terms of

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Which compound can be used as a reducing agent in a reaction?

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A measure of the degree of disorderliness in a chemical system is known as the

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How much sodium hydroxide is required to nka 250 cm3 ofa0.1 molar solution? Na=23; 0=16; H=1]

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What is the ratio of the rate of diffusion of carbon(IV) oxide to that of propane, under the same conditions? [H = 1; C= 12; 0= 161

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Fructose and glucose are

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The molar mass of a compound X is 56. its empirical formula is CH2. X is

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White is NOT a property of metals?

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Which compound is a product of the hydrolysis of the of CH₃COOC₃H₇ with aqueous sodium hydroxide?

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what dose the following equation illustrate? \( ^{238}U_{92} → ^{234}Th_{90} + ^4 He_2 \)

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The Atomic theory model which explains that electrons in an atom revolve round quantized energy levels is attributed to

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Which compound will have the lowest boiling point?

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The green colour solution of an Fe2 salt changes to a brown solution of an Fe3+ salt by

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Which method is NOT used to determine rate of a reaction?

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in any chemical reaction, the total mass of products is always equal to that of the reactants.

This Is statement of the law of:

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The position of an element in the Periodic Table is determined by

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The Kinetic theory can NOT be used to explain

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if an element X with atomic number 13 combines with an element Y whose atomic number is 8 the most likely formula of the compound formed between X and Y is?

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Which of the following is TRUE of a catalyst? I. it alters the activation energy of a reaction
II. it is effective in a reaction but cannot initiate a reaction
III, it affects the equilibrium of a reversible reaction
IV. it affects the overall reaction

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Which metal will dissolve in aqueous sodium hydroxide?

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20 cm³ of 0.09 mol dm³ solution of tetraoxosuiphate (Vi) acid requires 30cm³ of sodium hydroxide solution for complete neutralization. The molar concentration of sodium hydroxide is [H = 1; S = 32; 0 = 16; Na = 23]

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On exposure to hydrogen sulphide, moist lead (II) ethanoate paper turns

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