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Equal volumes of water were added to one mole of each of the following compounds. Which of them produced the largest number of ions
AGlucose
BSodium trioxonitrate (V)
CEthananoic acid
DSilver chloride
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Question 1452
waec1999
Which of the following is not correct about oxidation number convention? The oxidation number of a/an
Aelement in the free state is zero
Bmonatomic ion is equal to its charge
Calkali meta like sodium in its compounds is + 1
Datom of a diatomic molecules is + 2
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Question 1453
waec1999
What will be the effect of increase in pressure on the following system at equilibrium? 2NH2(g) N2(g) + 3H2(g)
AActivation energy will decrease
Bthe forward reaction will be favoured
Cthe concentration of ammonia will increase
Dthe reaction will go to completion
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Question 1454
waec1999
Consider the reaction represented by the following equation: H2(g) + 12(g) → 2HI(g). The number of effective collisions of molecules of the reactants decreases as
Athe temperature is raised
Bthe pressure increased
Cthe volume of the system is increased
Da catalysty is intoduced into the system
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Question 1455
waec1999
Which of the following lowers the activation energy of a chemical reaction?
AFreezing mixture
BReducing agent
CWater
DCatalyst
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Question 1456
waec1999
The property of calcium chloride which makes it useful as a drying agent is that it is
Aionic
Bdeliquescent
Ca strong electrolyte
Da normal salt
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Question 1457
waec1999
If the solubility of KHCO3 is 0.40 mole dm-3 at room temperature , calculate the mass of KHCO3 in 100dm3 of the solution at this temperature. [KHCO3 = 100hmol
A4.0g
B10.0g
C40.0g
D100.0g
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Question 1458
waec1999
Which of the following compounds dissolves in water to form a solution with pH below 7?
ASodium tetraoxosulphate (VI)
BPotassium hydroxide
CAmmonium chloride
DSodium trioxocarbonate (IV)
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Question 1459
waec1999
Which of the following is an acid salt?
ANH4CI
BMgSO4 7H2O
CCH3COONa
DNaHCO3
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Question 1460
waec1999
An exothermic reaction is one which involves
Aattainment of dynamic equilibrium
Bloss of heat to the surrounding
Cevolution of gas as it proceeds
Dpositive change in value of enthalpy
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Question 1461
waec1999
30cm3 pf hydrogen at s.t.p combine with 20cm3 of oxygen to form steam according to the following equation 2H2(g) + O2(g) → 2H2O(g).
Calculate the total volume of the gaseous mixture at the end of the reaction
A50cm3
B35cm3
C30cm3
D25cm3
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Question 1462
waec1999
Helium is preferred to hydrogen in filling balloons because hydrogen
Ais inflammable
Bis diatomic
Cexhibits isotopy
Dis a component of water
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Question 1463
waec1999
What volume of hydrogen is produced at s.t.p. When 2.60 g of zinc reacts with excess HCI according to the following equation? Zn(s) + 2HCI(aq) → ZnCI 2(aq) + H2(g) [Zn = 65; 1 mole of a gas occupies 22.4dm3 at s.t.p]
A0.040dm 3
B0.896dm 3
C5.82dm 3
D8.62dm 3
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Question 1464
waec1999
Gas molecules are said to be perfectly elastic because
Athey collide without loss of energy
Bthey move about in straight lines
Cthe distances between them are negligible
Dthe volume occupied by them is negligible
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Question 1465
waec1999
Equal volumes of CO2 cnd CO at s.t.p have the same
Amass
Bdensity
Crate of diffusion
Dnumber of molecules
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Question 1466
waec1999
Which of the following movements can be described as random motion?
Awheelbarrow being pushed
Bcar travelling on a straight line
CGas molecules colliding in a flask
DPlanets going round the sun
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Question 1467
waec1999
Exhaust fumes discharged from a smoky vehicle gradually become invisible as a result of
Adiffusion
Bcombustion
Cabsorption
Demission
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Question 1468
waec1999
One mole of a compound M(HCO3)2 has a mass of 162g. Calculate the relative atomic mass of M. [H = 1, C =12, O = 16]
A122
B101
C53
D40
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Question 1469
waec1999
If an element with high electron affinity combines with another element with low ionization energy the bond formed will be mainly
Acovalent
Bionic
Cdative
Dmetallic
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Question 1470
waec1999
Which of the following compounds has the highest ionic character?
