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2X(g) + Y(g) → Z(g): In the equation above, The rate of formation of Z is found to be independent of the concentration of Y and to quadruple when the concentration of X is doubled. The correct equation for the reaction is?
AR = k (X)(Y)
BR = K (X) ° (Y)
CR = K (X) ° (Y) 2
DR = K (X) 2(Y)°
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Question 792
jamb1998
2Cl2(g) + 2H2O(g) 4HCl(g) + O2(g)
∆H° = +115KJ mol-1. In the above equilibrium reaction, a decrease in temperature will?
Afavour the reverse reaction
Bfavour the forward reaction
Chave no effect on the equilibrium state
Ddouble the rate of the reverse raection
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Question 793
jamb1998
Mg2+(aq) + 2e->(aq) → Mg(s)E°(volts) = 2.370
Zn2+(aq) + 2e->(aq) → Zn(s)E°(volts) = -0.763
Cds2+(aq) + 2e->(aq) → Cd(s)E°(volts) = 0.403
Cu2+(aq) + 2e->(aq) → Cu(s)E°(volts) = 0.340
In the electrochemical series above, the strongest reducing agents is?
ACu (s)
BCd(s)
CZnsub>(s)
DMg(s)
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Question 794
jamb1998
The pH of a solution obtained by mixing 100cm\(^3\) of a 0.1M HCl solution with 100cm\(^3\) of a 0.2M solution of NaOH is?
A1.3
B7.0
C9.7
D12.7
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Question 795
jamb1998
Soap lather is an example of a colloid in which a?
Aliquid is dispersed in gas
Bsolid is dispersed in liquid
Cgas is dispersed in liquid
Dliquid is despersed in liquid
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Question 796
jamb1998
90.0g of MgCI2 was placed in 50.0cm3 of water to give a saturated solubility of the salt is 8.0 mol dm3 at the same temperature, what is the mass of the salt left undissolved at the given temperature?
(Mg = 24, Cl = 35.5)
A52.0g
B58.5g
C85.5g
D88.5g
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Question 797
jamb1998
If an element X of an atomic number Z and mass number Y is irradiated by an intense concentration of neutrons, the relevant nuclear equation is?
AyzX + 10n → y - 1z + 1X
ByzX + 10n → y + 1zX
CyzX + 10n → yz + 1X
DyzX + 10n → y + 1z - 1X
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Question 798
jamb1998
Excess phosphorus was burnt in a gas jar and the residual gas passed successively over concentrated KOH solution and concentration H2SO4 before being collected in a flask. The gases collected are?
Acarbon (IV) oxide, nitrogen and the rare gases
Bnitrogen and the rare gases
Ccarbon (IV) oxide, nitrogen (IV) oxide and the rare gases
Dcarbon (IV) oxide
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Question 799
jamb1998
The soil around a battery manufacturing factory is likely to contain a high concentration of?
ACa2+ salts
BPb2+ salts
CMg2+ salts
DAl3+ salts
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Question 800
jamb1998
Potassium tetraoxomanganate (VII) is often added to impure water to?
Areduce organic impurities
Breduce inorganic impurities
Cdestroy bacteria and algae
Dremove permanent hardness
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Question 801
jamb1998
The property used in obtaining oxygen and nitrogen industrially from air is the?
Aboiling point
Bdensity
Crate of diffusion
Dsolubility
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Question 802
jamb1998
The line observed in the sample hydrogen spectrum are due to emission of?
Aelectrons from the atoms
Benergy by proton transition
Cenergy by electron transition
Dneutron from the atom
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Question 803
jamb1998
Which of the following electron configurations indicates an atom with the highest ionization energy?
A2,8,7
B2,8,8,1
C2,8,8,2
D2,8,8,7
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Question 804
jamb1998
A solid begins to melt when?
Aconstituent particles acquires a greater kinetic energy
Benergy of vibration of particles of the solid is less than the intermolecular forces
Cconstituent particles acquires energy above the average kinetic energy
Denergy of vibration of particles of the solid equals the intermolecular forces
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Question 805
jamb1998
If sulphur (IV) oxide and methane are released simultaneously at the opposite ends of a narrow tube, the rates of diffusion Rso2 and Rch4 will be in the ratio?
(S = 32, O = 16, C = 12, H = 1)
A4:1
B2:1
C1:2
D1:4
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Question 806
jamb1998
30cm3 of hydrogen was collected over water at 27°C and 780 mm Hg. If the vapour pressure of water at the temperature of the experiment was 10 mm Hg, calculate the volume of the gas at 760 mm Hg and 7°C?
A40.0 cm3
B35.7 cm3
C28.4 cm3
D25.2 cm3
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Question 807
jamb1998
C3H8(g) + 502(g) → 4H2O + 3CO2(g). Form the equation above the volume of oxygen at s.t.p. required to burn 50cm3 of propane is?
A250 cm3
B150 cm3
C100 cm 3
D50 cm3
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Question 808
jamb1998
8.0 g of an element X react with an excess of copper (ll) tetraoxosulphate (lV) solution to deposit 21.3 g of copper. The correct equation for the reaction is?
(Cu = 64).
AX(s) + CuSO4(aq) → Cu(s) + XSO4(aq)
BX(s) + 2CuSO4(aq) → 2Cu(s) + X(SO4)2(aq)
C2X(s) + CuSO4(aq) → Cu(s) + X2SO4(aq)
D2X(s) + 3CuSO4(aq) → 3Cu(s) + X2(SO4)3(aq)
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Question 809
jamb1998
A given amount of gas occupies 10.0 dm3 at 4atm and 273°C. The number of moles of the gas present is?
(Molar volume of a gas at s.t.p. = 22.4 dm3)
A0.89 mol
B1.90 mol
C3.80 mol
D5.70 mol
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Question 810
jamb1998
A mixture of iron and sulphur can be separated by dissolving the mixture in?
