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What is the percentage by weight of calcium in Ca(OCI)2? [Ca = 40, Cl = 35.5, O = 16]
A28.0%
B31.6%
C43.8%
D44.5%
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Question 942
waec2009
Consider the reaction represented by the equation: 2NaHCO3 → Na2CO 3 + H 2O + CO 2. What is the mass of sodium trioxocarbonate (lV) produced by the complete decomposition of 33.6 g of sodium hydrogen trioxocarbonate (IV)? [NaHCO3 = 84, Na2CO3 = 106]
A10.6 g
B16.8 g
C21.2 g
D42.4 g
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Question 943
waec2009
How many molecules are there in 14 g of nitrogen at s.t.p.? [N = 14, Avogadro's c x 10\(^{23}\) mol-1]
A6.02 x 1023
B3.01 x 1023
C8.43 x 1024
D1.20 x 1024
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Question 944
waec2009
The number of particles in one mole of a chemical compound is the
Aatomic number
Bavogadro's number
Cmass number
Doxidation number
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Question 945
waec2009
Which of the following molecules is not linear in shape?
ACO2
BO 2
CNH3
DHCI
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Question 946
waec2009
In bonded atoms, increase in electronegativity difference,
Aincreases polarity
Bdecreases polarity
Chas no effect on polarity
Dbrings the polarity to zero
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Question 947
waec2009
Which of the following arrangements is in order of increasing ionization energy?
AAI, Si, P, S
BSi, AI,S,P
CS,P,Si,AI
DP, Si,S,AI
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Question 948
waec2009
Which of the following properties of covalent compounds is not correct? They
Aare non-electrolytes
Bare mostly gaseous and volatile liquids
Chave low melting point
Dhave high boiling points
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Question 949
waec2009
Which of the statements about the behaviour of the atom is correct?
Aatomic size decreases down the group
Batomic size increases across the period
Canions are smaller than the parent atom
Dcations are smaller than the parent atom
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Question 950
waec2009
An element Q forms a compound QCI5. In which group of the periodic table is Q?
Al
Blll
CV
DVII
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Question 951
waec2009
Which of the following electronic configurations correctly represents an element in period 3 of the periodic table?
A1s2 2s2 2p2
B1s2 2s2 2p6
C1s2 2s2 2p6 3s2 3p4
D1s2 2s2 2p6 3s2 3p6 4s1
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Question 952
waec2009
Which of the following ions is isoelectronic with neon? [\(_3\)Li, \(_9\)F, \(_{10}\)Ne, \(_{17}\)CI,\(_{19}\)K ]
ACI-
BF-
CK+
DLi,+
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Question 953
waec2009
The following properties are characteristics of transition elements except
Aformation of complex ions
Bfixed oxidation states
Cformation of coloured compounds
Dcatalytic abilities
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Question 954
waec2009
Which of the following elements has the electronic configuration:1s22s22p63s23p1? [11Na, 13A1, 14N,16S]
AAl
BNa
CN
DS
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Question 955
waec2009
How many orbitals are associated with the p-sub energy level?
A2
B3
C5
D6
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Question 956
waec2009
Consider the reaction represented by the equation: 23892U + 10 → 13956Ba + 9436Kr + 310n. The reaction represents a
Anuclear fission
Bnuclear fusion
Cradioactive decay
Dspontaneous disintegration
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Question 957
waec2009
If 100 atoms of element X contains 70 atoms of 9X and 30 atoms of 11X, calculate the relative atomic mass of X
A9.6
B10.6
C11.6
D20.0
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Question 958
waec2009
How many protons does 4020Ca contain?
A20
B30
C40
D60
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Question 959
waec2009
Which of the following scientists discovered the neutron?
AErnest Rutherford
BJ.J Thompson
CJames Chadwick
DR. A. M illikan
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Question 960
jamb2009
If the relative atomic mass of an element is not a whole number, it can be deduced that the element is?
