NECO SSCE - Chemistry - 2009

Sulphur has an oxidation number of +4 in

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The green house effect is a climatic condition associated with the presence of excess

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During the extraction of iron in the blast furnance, slag is produced using

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X = - log₁₀ H⁺]

What does X stand for in the expression above?

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Which of these compounds has the greatest ionic character?

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Which of the following metals is NOT extracted by electrolysis?

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Which of the following gases is absorbed from the air dun photosynthesis?

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Which of the following salt solutions will have a pH greater than 7?

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All the following belong to the same family EXCEPT

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How many zones are present in a luminous Bunsen burner flame?

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When air is passed through alkaline pyrogallol and then lime water, the gases left are

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The percentage composition of a hydrocarbon is 79.2 carbon 20.8 hydrogen. Calculate its empirical formula [H = 1, C = 12]

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Which of the following statements is NOT correct of group VII elements? They

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A salt which loses its mass when exposed to air is

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The reaction of an alkanol with alkanioc acid is known as

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Which of the following non-metals reacts most readily with metals?

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The Ideal Gas Law is expressed mathematically as

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\( ^{235}_{92}U + ^1_0n → ^{145}_{56}Ba + ^{88}_{36}Kr + 3^1_0n + Energy \)

The equation above represent a/an

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Which of the following gases will bleach moist litmus paper?

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A neon atom is chemically nonreactive because

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Which of the following is NOT a fraction of petroleum?

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What volume of carbon (IV) oxide in dm ³ is produced at s.t.p. when 2.50g of CaCO₃ reacts with excess acid according to the following equation? CaCO₃(s) + 2HCI(aq) → CaCl₂(aq) + H₂O(1) + CO₂(g)

[CaCO₂ 100; molar volume of a gas at s.t.p. = 22.4dm ³]

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The empirical formula of a hydrocarbon containing 0.12 mole of carbon 0.3 mole of hydrogen is

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Two elements X and Y with electronic configurations 2,8,2 and 2,8,7 respectively, are likely to combine by _________bonding

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The following are ores of metals EXCEPT

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The relationship between equilibrium constant and free energy change is represented as

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The rate of a reaction usually increases with increase in the concentration of reactants because the

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Non-polar molecules are held together by

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Which of the following compounds will undergo thermal dissociation?

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Ptotal = P1 + P2 + P3 +…………. Pn, is an expression of law

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What mass of copper in gram would be deposited by a current of 1.00ampere passing for 965 seconds through copper(II) tertraoxosulphate (VI) solution? [Cu 63.5; If = 96500c]

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Compound with the general formula CnH\(_{2n+2}\) belong to the_______ group

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C\(_6\)H\(_{12}\)O\(_6\)

What is the molar mass of the compound above?

[ H=1, C=12, O=16 }

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Atomic size decreases

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A colourless gas with characteristics odour which dissolves in water to form an alkaline solution is

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The following equations represent redox reactions EXCEPT

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Brain tumors can be located by using an isotope of

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The furring of kettles and boilers are caused by

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In the electrolysis of dilute tetraoxosulphate (VI) acid using platinum electrodes, the products obtained at the anode are cathode respectively are

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The scientist who discovered the zig-zag movement of gas molecules is

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The process involved in the decomposition of sugar by an enzyme is called

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Which of the following equations is NOT balanced?

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The following compounds decolorize acidified potassium tetraoxomanganate (VII) solution EXCEPT

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If the volume of a gas at 35°C is 60cm³, what would be its volume in cm³ at 273k?

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What kind of bond exist between carbon and oxygen in C0₃ ^2-?

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Which of the following is a solid at room temperature?

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How many atoms of chlorine are required to saturate the double bonds of a compound containing a triene?

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