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A pair of compounds that can be used to generate a gas which has physiological effect on human beings is
Asodium trioxonitrate (V) and calcium chloride
Bsodium dioxonitrate (III) and ammonium chloride
Csodium trioxonitrate (V) and ammonium chloride
Dsodium dioxonitrate (III) and potassium chloride
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Question 32
jamb1999
The salt that reacts with dilute hydrochloric acid to produce a pungent smelling gas which decolourizes acidified purple potassium tetraoxomanganate (VII) solution is
ANa2SO4
BNa2SO3
CNa2S
DNa2CO3
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Question 33
jamb1999
Chlorine, bromine and iodine resemble one another in that they?
Adissolve in alkalis
Breact violently with hydrogen without heating
Care liquids
Ddisplace one another from solutions of their salts
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Question 34
jamb1999
The gas that will form a white precipitate with acidified silver trioxonitrate (v) is
ANH3
BSO2
CCO2
DHCL
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Question 35
jamb1999
Which of the following statement is true of the electrochemical series?
AElectropositivity of metals increase down the series
BElectropositivity of non-metals decrease down the series
CElectronegativity of non-metals decrease down the series
DElectropositivity of metals decreases down the series
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Question 36
jamb1999
RS(aq) + HF(aq) → RF(s) + HS(aq)
ΔH = -65.7 kj mol(-1).
From the equation above, it can be deduced that
Athe heat content of the reactants is lower than that of the products
Bthe heat content of the reactants is higher than that of the products
Cthe reaction is slow
Da large amount of heat is absorbed
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Question 37
jamb1999
When a current I was passed through an electrolyte solution for 40 minutes, a mass X g of a univalent metal was deposited at the cathode. What mass of the metal will be deposited when a current 2I is passed through the solution for 10 minutes?
AX/4 g
BX/2 g
C2X g
D4X g
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Question 38
jamb1999
X + Y → Z. The rate equation for the chemical reaction above is \(\frac{-Δx}{Δt}\) = K[X]\(^2\)[Y].
The overall order of the reaction is?
A0.0
B1.0
C2.0
D3.0
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Question 39
jamb1999
What quantity of electricity will liberate 0.125 mole of oxygen molecules during the electrolysis of dilute sodium chloride solution?
[ F = 96 5000 C mol-1 ]
A24 125 coulombs
B48 250 coulombs
C72 375 coulombs
D96 500 coulombs
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Question 40
jamb1999
N\(_2\)O\(_4\)(g) ↔ 2NO\(_2\)(g). Increase in total pressure of the equilibrium reaction above will
Aproduce more of NO2(g) in the mixture
Bconvert all of N2O4(g) to NO2(g)
Chave no effect on the concentrations of NO2(g)and N2O4(g)
Dproduce more of N2O4(g) in the mixture
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Question 41
jamb1999
2SO2(g) + O2(g) ↔ 2SO3(g). In the chemical reaction above, the substance that will increase the rate of production of sulphur (VI) oxide is
Amanganese (IV) oxide
Bfinely divided iron
Cvanadium (V) oxide
Dnickel
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Question 42
jamb1999
The entropy and enthalpy of a system are a measure of
Adegree of disorderlinesss and heat content respectively
Bheat content and degree of disorderliness respectively
Cheat content of a system only
Ddegree of disorderliness only
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Question 43
jamb1999
The solubility product of Cu(IO3)2 is 1.08 * 10-7. Assuming that neither ions react appreciable with water to form H+ and OH-, what is the solubility of this salt?
A2.7 * 10-8 mol dm-3
B9.0 * 10-8 mol dm-3
C3.0 * 10-3 mol dm-3
D9.0 * 10-3 mol dm-3
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Question 44
jamb1999
The solution with the lowest pH value is
A5 ml of (m/10) HCl
B10 ml of (m/10) HCl
C15 ml of (m/5) HCl
D20 ml of (m/8) HCl
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Question 45
jamb1999
What is observed when aqueous solutions of each of tetraoxosulphate (VI) acid, potassium trioxoiodate (V) and potassium iodide are mixed together?
AA white precipitate is formed
BA green precipitate is formed
CThe mixture remains colourless
DThe mixture turns reddish brown
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Question 46
jamb1999
The set of pollutants that is most likely to be produced when petrol is accidentally spilled on plastic materials and ignited is
ACO, CO2 and SO2
BCO, HCL and SO2
CCO, CO2 and HCL
DSO2, CO2 and HCL
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Question 47
jamb1999
The correct order of increasing oxidation number of the transition metal ions for the compounds K2Cr2O7, V2O5 and KMnO4 is
AV2O5 < K2Cr2O7 < KMnO4
BK2Cr2O7 < KMnO4 < V2O5
CKMnO4 < K2Cr2O7 < V2O5
DKMnO4 < V2O5 < K2Cr2O7
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Question 48
jamb1999
0.25 mole of hydrogen chloride was dissolved in distilled water and the volume made up of 0.50 dm3. If 15.0 cm3 of the solution requires 12.50 cm3 of aqueous sodium trioxocarbonate (IV) for neutralization, calculate the concentration of the alkaline solution
A0.30 mol dm3
B0.40 mol dm3
C0.50 mol dm3
D0.60 mol dm3
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Question 49
jamb1999
Given that electronegativity increases across a period and decreases down a group in the periodic table, in which of the following compounds will the molecules be held together by the strongest hydrogen bond?
AHF(g)
BNH3(g)
CCH4(g)
DHCl(g)
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Question 50
jamb1999
1s2, 2s2, 2p6, 3s2, 3p6, 3d7, 4s2
An element with the electronic configuration above is a
