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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 612
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 613
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 614
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 615
waec1999
Exhaust fumes discharged from a smoky vehicle gradually become invisible as a result of
Adiffusion
Bcombustion
Cabsorption
Demission
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Question 616
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 617
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 618
waec1999
Which of the following compounds has the highest ionic character?
APCI5
BSiCI4
CAICI3
DKCI
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Question 619
waec1999
The crystal layers in graphite are held together by
Aelectrostatic forces
Bvan der Waals' forces
Chydrogen bonds
Dcovalent bonds
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Question 620
waec1999
Which of the following halogens is the most reactive?
AF2
BBr2
Cl2
DCl
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Question 621
waec1999
Which of the following reactions is not feasible?
ACl2 + 2Kl → 2KCI + I2
BCl2 + 2NaF → 2NaCI + F2
CZn + CuCI2 → ZnCl2 + Cu
DZn + 2AgNO3 → Zn(NO3)2 + 2Ag
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Question 622
waec1999
In the Periodic Table, the elements that loss electrons most readily belong to
AGroup 1 A
BGroup 11 A
CGroup 111 A
DGroup V11 A
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Question 623
waec1999
Which of the following properties increases down a group in the Periodic Table?
AAtomic radius
BElectronegativity
CElecton affinity
DIonization energy
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Question 624
waec1999
Calcium atom ionizes by
Againing two electrons
Blosing two electrons
Csharing two electrons
Dgaining two protons
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Question 625
waec1999
Two radioactive elements Q and S have half-life periods of 10 hours and 20 hours respectively. Therefore
AS decays faster than Q
BQ is twice as stable as S
CQ emits fewer particles than S
DS is more stable than Q
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Question 626
waec1999
Which of the orbitals 4s, 4p, 4d and 4f has the lowest energy?
A4f
B4p
C4d
D4s
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Question 627
waec1999
Pauli Exclusion Principle is related to
Aquantum numbers of electrons
Breversiblility of equlibrium reactions
Celectronegativity values of elements
Dcollision theory of reaction rates
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Question 628
waec1999
What is the electronic configuration of an element represented as 199X?
A1s 22s2 2p 5
B1s22s23s23p3
C1s2 2s2 2p 33s2
D1s 22s22p 63s23p64s 1
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Question 629
waec1999
Which of the following atoms contains the highest number of electrons in the outermost shell?
A8O
B10Ne
C15P
D19K
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Question 630
waec1998
Which of the following compounds is used as a gaseous fuel?
