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The solubility of copper (II) tetraoxosulphate (Iv) is 75g in 100g of water at 100°C and 25g in 100g of water at 30°C. What mass of the salt would crystallize, if 50g of copper (II) tetraoxosulphate (VI) solution saturated at 100°C were cooled to 30°C ?
A57.5
B42.2
C28.6
D14.3
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Question 942
jamb1991
Which of the following ions is a pollutant in drinking water even in trace amounts?
ACa2+
BHg2+
CMg2+
DFe2+
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Question 943
jamb1991
A quantity of air was passed through a weighed amount of alkaline pyrogallol. An increase in the weight of the pyrogallol would result from the absorption of?
Anitrogen
Bneon
Cargon
Doxygen
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Question 944
jamb1991
Which of the following is arranged in order of increasing electronegativity?
Which of the following represents the type of bonding present in ammonium chloride molecule?
AIonic only
BCovalent only
CIonic and dative covalent
DDative covalent only
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Question 946
jamb1991
The ions X- and Y+ are isoelectronic, each containing a total of 10 electrons.
How many protons are in the nuclei of the neutral atoms of X and Y respectively?
A10 and 10
B9 and 9
C11 and 9
D9 and 11
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Question 947
jamb1991
The electronic configuration of an elements is 1s22s22p63s23p3. How many unpaired electrons are there in the element?
A5
B4
C3
D2
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Question 948
jamb1991
Atoms of element X (with 2 electrons in the outer shell). combine with atoms of Y (with 7 electrons in the outer shell). Which of the following statements is FALSE? The compound formed?
Ahas formula XY
Bis likely to be ionic
Ccontains X2+ ions
Dcontains Y- ions
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Question 949
jamb1991
A sample of a gas exerts a pressure of 8.2 atm when confined in a 2.93 dm3 container at 20°C. The number of moles of gas in the sample is?
(R = 0.082 litre atm / deg mole)
A1.00
B2.00
C3.00
D4.00
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Question 950
jamb1991
A given quantity of a gas occupies a volume of 228 cm3 at a pressure of 750mm Hg. What will be its volume at atmospheric pressure?
A220 cm3
B225 cm3
C230 cm3
D235 cm3
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Question 951
jamb1991
Calculate the volume of carbon (IV)oxide measured at s.t.p, produced when 1 kg of potassium hydrogen trioxocarbonate (IV) is totally decomposed by heat?
(G.M.V. at s.t.p 22.4 dm3, K = 39, O = 16, C = 12, H = 1)
A28 dm3
B56 dm3
C112 dm3
D196 dm3
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Question 952
jamb1991
30cm\(^3\) of oxygen at 10 atmospheres pressure is placed in a 20 cm\(^3\) container. Calculate the new pressure if temperature is kept constant?
A6.7 atm
B15.0 atm
C60.0 atm
D66. 0 atm
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Question 953
jamb1991
In two separate experiments, 0.36g and 0.71g of chlorine combined with a metal X to give Y and Z respectively. An analysis showed that Y and Z contain 0.20g and 0.40g of X respectively. The data above represents the law of ?
Amultiple proportion
Bconservation of mass
Cconstant composition
Dreciprocal proportion
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Question 954
jamb1991
An iron ore is known to contain 70.0% Fe2O3. The obtain from 80kg of the ore is?
(Fe = 56, O = 16)
A35.0 kg
B39.2 kg
C70.0 kg
D78.4 kg
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Question 955
jamb1991
Which of the following are mixtures?
i, Petroleum
ii, Rubber latex
iii. Vulcanizer's solution
iv, Carbon (II)sulphide
Ai, ii and iii
Bi, ii and iv
Ci and ii only
Di and iv
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Question 956
jamb1991
Which of the following can be obtained by fractional distillation?
ANitrogen from liquid air
BSodium chloride from sea water
CIodine from a solution of Iondine in carbon tetrachloride
DSulphur from a solution of sulphur incarbon disulphide
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Question 957
jamb1990
The Avogadro number of 24g of magnesium is the same as that of
A1g of hydrogen molecules
B16g of oxygen molecules
C32g of oxygen molecules
D35.5g of chlorine molecules
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Question 958
jamb1990
Select the right answer from the structure above.Which of the following compounds represents the polymerization product of ethyne?
AA
BB
CC
DD
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Question 959
jamb1990
The above reaction is an example of
Aa displacement reaction
Ba neutralization reaction
Can elimination reaction
Dsaponification
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Question 960
jamb1990
CH3-C = CH \(\frac{Na}{liq NH_3}\)> P, Compound P, in the above reaction, is
