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Chemistry WAEC / WASSCE 2011 Matter & Separation Techniques
Rare gases are stable because they
A
contain equal number of protons and neutrons
B
contain more electrons than protons
C
are chemically active
D
have octet structure
medium Difficulty
Chemistry WAEC / WASSCE 2011 Matter & Separation Techniques
Which of the following elements would produce coloured ions in aqueous solution?
A
Calcium
B
lron
C
Magnesium
D
Sodium
medium Difficulty
Chemistry WAEC / WASSCE 2011 Atomic Structure and Periodic Table
The energy change that accompanies the addition of an electron to an isolated gaseous atom is
A
bond energy
B
electronegativity
C
electron affinity
D
ionization energy
medium Difficulty
Chemistry WAEC / WASSCE 2011 Acids, Bases, and Salts
Which of the following hydrohalic acids is the weakest?
A
HBr
B
HCI
C
HF
D
HI
medium Difficulty
Chemistry WAEC / WASSCE 2011 Matter & Separation Techniques
Which of the following arrangements is in order of increasing metallic property?
A
Li < Na< k
B
Na < Li < K
C
K
D
K < Li < Na
medium Difficulty
Chemistry WAEC / WASSCE 2011 Matter & Separation Techniques
Chlorine, bromine and iodine belong to the same group and
A
are gaseous at room temperature.
B
form white precipitate with AgNO3(aq)
C
react violently with hydrogen without heating
D
react with alkali
medium Difficulty
Chemistry WAEC / WASSCE 2011 Atomic Structure and Periodic Table
Which of the following elements can conveniently be placed in two groups in the periodic table ?
A
Carbon
B
Copper
C
Hydrogen
D
Oxygen
medium Difficulty
Chemistry WAEC / WASSCE 2011 Atomic Structure and Periodic Table
The bond formed when two electrons that are shared between two atoms are donated by only one of the atoms is
A
covalent
B
dative
C
ionic
D
metalic
medium Difficulty
Chemistry WAEC / WASSCE 2011 Matter & Separation Techniques
When element 20A combines with element 8Y,
A
a covalent compound, AY is formed
B
an ionic compound AY is formed
C
an ionic compound, A2Y is formed
D
a covalent compound, AY2 is formed
medium Difficulty
Chemistry WAEC / WASSCE 2011 Atomic Structure and Periodic Table
In metallic colids, the forces of attraction are between the mobile valence electrons and
A
atoms
B
neutrons
C
the negative ions
D
positively charged nuclei
medium Difficulty
Chemistry WAEC / WASSCE 2011 Matter & Separation Techniques
Which of the following statements about displacement reaction is correct?
A
A more electropositive element displaces a less electroposive one
B
A less electropositive element displaces a more electropositive one
C
The position of elements in the reactivity series has no effect on the reaction
D
it only occurs when the reaction is at equilibrium
medium Difficulty
Chemistry WAEC / WASSCE 2011 Stoichiometry & Mole Concept
The volume occupied by 17g of H2S at s.t.p. is [H = 1.00, S = 32.0, Molar volume = 22.4 dm3]
A
11.2dm 3
B
17.0 dm3
C
34.0dm 3
D
44.8dm 3
medium Difficulty
Chemistry WAEC / WASSCE 2011 Matter & Separation Techniques
Consider the reaction represented by the following equation: xKMnO 4(aq) + ySO2(g) + zH2O(I) → K 2SO4(AQ) + 2MnSO4(aq) + 2H2SO x,y and z are respectively
A
2,5 and 2
B
2,2 and 5
C
5, 1 and 2
D
1, 5 and 2
medium Difficulty
Chemistry WAEC / WASSCE 2011 Stoichiometry & Mole Concept
What is the amount of magnesium that would contain 1.20 x 1024 particles? [Mg = 24, Avogadro's constant = 6.02 x 1023]
A
0.5 moles
B
2.0 moles
C
12.0 moles
D
24.0 moles
medium Difficulty
Chemistry WAEC / WASSCE 2011 Stoichiometry & Mole Concept
The number of atoms in one mole of a substance is equal to the
A
mass number
B
oxidation number
C
atomic number
D
avogadro number
medium Difficulty
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