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The boiling point of water is higher than the boiling point of ethanol because
Athe bonding in water is electrovalent (ionic) whereas the bonding in ethanol is convalent
Bthe hydrogen bonding between water molecules is stronger than the hydrogen bonding between ethanol molecules
Cwater has a higher lattice energy than ethanol.
Dwater has hydrogen bonding between its molecules but ethanol has no hydrogen bonging between its molecules;
Ewater is a better solvent than ethanol.
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Question 64
neco2003
B is an isotope of the element \(^{238} _{92}Ur\). The isotope B has
A46 protons and 119 neutrons
B92 protons and 92 neutrons
C92 protons and 146 neutrons
D92 protons and 238 neutrons
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Question 65
neco2003
The number of hydrogen ions in 1.0dm\(^3\) of a 0.25 mole tetraoxosulphate(Vl) acid solution is
[Avogadro c x 10\(^{23}\)]
A1.45x1023
B1.50 x l023
C3.00x1023
D3.15x1023
E6.00x1023
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Question 66
neco2003
Chlorine is used in water purification because it
Ableaches impurities in the water
Bdecolorizes water
Cdestroys bacteria
Dis extremely soluble in water
Eis pleasant tasting
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Question 67
neco2003
Which statement is NOT true about the composition of starch?
AIt contains only the atoms of carbon, hydrogen oxygen
BIt is a polysaccharide
CIts empirical formula is C2H20.
DIt is made from the monomerC6H12O6.
EThe hydrogen and oxygen atoms are in the ratio 2:1.
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Question 68
neco2001
Which compound is a component of baking powder?
ANa2CO3
BNa2SO4
CKH2CO3
DNaHCO3
ENaHSO4
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Question 69
neco2001
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?
AXY
BX2Y
CXY2
DX3Y2
EX2Y3
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Question 70
neco2001
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.?
A164 cm3
B168 cm3
C179.1.cm3
D201.5cm3
E546 cm3
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Question 71
neco2001
A measure of the degree of disorderliness in a chemical system is known as the
Aactivation energy
Benthalpy
Centropy
Dequilibrium
Efree energy.
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Question 72
neco2001
Fructose and glucose are
Aallotropes of each other.
Bboth disaccharides
Cdimere of each other.
Disomers of each other
Eisotopes of each other
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Question 73
neco2001
Detergents are better than soaps for washing in hard water because
Ahard water contains insoluble calcium salts.
Bthey contain bleaching powder.
Cthey contain palmitic acid.
Dthey do not form insoluble calcium and magnesium salts.
Ethey are organic compounds.
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Question 74
neco2001
Which method is NOT used to determine rate of a reaction?
Achange in amount of precipitate formed
Bchange in equilibrium constant
Cchange in intensity of colour
Dchange in pH values.
Echange in total gas pressure
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Question 75
neco2001
Ethanol is a product of fermentation of simple sugars. Which method is used to separate ethanol from the other products?
Aboiling off the ethanoic
Bfiltration
Cfractional crystallisation
Dfractional distillation
Eisomerisation
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Question 76
neco2001
To test for the presence of chloride ions in ion, correct sequence of reagents to use is
ABa(NO3)2(aq) then HNO3(aq).
BHCl(aq) then Ba(NO3)2(aq).
CHCl(aq) then Ag3(aq).
DHNO3(aq) then fresh FeSO4(aq).
EHNO3(aq) then AgNO3(aq).
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Question 77
neco2001
NaCl(s) does NOT conduct electricity, but N(aq) does. This is because
ANaCl(s) is non-ionic but NaCl(aq) is ion
BNaCl(aq) contains mobile electrons, where absent in NaCl(s).
CNaCl(aq) contains mobile ions which Nacl,) does not contain.
DNaCl(s) ionizes partiality while NaCl(aq) iodizes completely.
ENaCl(s) decomposes when heated but NCl(aq) is stable to heat. –
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Question 78
neco2001
The green colour solution of an Fe2 salt changes to a brown solution of an Fe3+ salt by
Aconversion.
Belimination.
Coxidation.
Dreduction.
Esubstitution.
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Question 79
neco2001
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.
A5
B12
C18
D45
E50
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Question 80
neco2001
Faraday s first law of electrolysis can be expressed mathematically as
