Which compound has the highest boiling point?
A ethanol
B heptane
C sodium chloride
D water
Your answer [1]
2 Pauling electronegativity values for
... [Show More] the halogens F to I and some elements in period 2 of the
periodic table are shown below.
B
2.04
C
2.55
N
3.04
O
3.44
F
3.98
Cl
3.16
Br
2.96
I
2.66
Which bond has the correct polarity?
A B C D
δ– N—I δ+ δ– C—F δ+ δ– B—Cl δ+ δ– Br—Cl δ+
Your answer [1]
3
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3 Which compound releases hydroxide ions when it dissolves in water?
A CH3COOH
B HNO3
C H2SO4
D NH3
Your answer [1]
4 Which alkane is 82.8% carbon by mass?
A CH4
B C2H6
C C4H10
D C8H18
Your answer [1]
5 Which gas sample has the greatest mass at RTP?
A 50cm3 of Ar(g)
B 100cm3 of O2(g)
C 150cm3 of N2(g)
D 200cm3 of Ne(g)
Your answer [1]
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6 A student mixes 250.0cm3 of 0.100moldm–3 KOH with 750.0cm3 of 0.100moldm–3Ca(OH)2.
What is the OH– concentration, in moldm–3, in the resulting mixture?
A 0.0250
B 0.100
C 0.150
D 0.175
Your answer [1]
7 After delivering a solution from a pipette, a droplet remains in the tip of the pipette.
How should a student ensure that the pipette delivers the volume of solution stated on the
pipette?
A Fill the pipette just above the graduation line to compensate for the volume of the droplet
that remains in the tip.
B Leave the droplet in the tip.
C Shake the pipette to force out the droplet left in the tip.
D Use a pipette filler to force the droplet out of the tip.
Your answer [1]
8 Which sequence has elements in order of increasing first ionisation energy?
A Na < Mg < Al
B Mg < Al < Si
C Al < Si < P
D Si < P < S
Your answer [1]
5
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9 Which element has atoms with the largest number of unpaired p-electrons?
A aluminium
B oxygen
C chlorine
D phosphorus
Your answer [1]
10 The equation for the complete combustion of propene, C3H6, is shown below.
C3H6(g) + 4½O2(g) → 3CO2(g) + 3H2O(l)
Standard enthalpy changes of formation, ∆f
Ho, are shown in the table.
Compound ∆f
Ho /kJmol–1
C3H6(g) +20
O2(g) 0
CO2(g) –394
H2O(l) –286
What is the standard enthalpy change of combustion of C3H6(g), in kJmol–1?
A –2060
B –700
C +700
D +2060
Your answer [1]
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11 The Boltzmann distributions below show a gas at two different temperatures.
Which Boltzmann distribution shows the dotted curve at a higher temperature?
A
number of
molecules
energy
B
number of
molecules
energy
C
number of
molecules
energy
D
number of
molecules
energy
Your answer [1]
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12 Which statement about dynamic equilibrium is not correct?
A A catalyst increases the rate of both forward and reverse reactions by the same amount.
B Dynamic equilibrium exists only in a closed system.
C The concentrations of the reactants and products are equal.
D The rate of the forward reaction is equal to the rate of the reverse reaction.
Your answer [1]
13 What is the number of unsaturated isomers (structural and stereoisomers) that have the molecular
formula C4H8?
A 3
B 4
C 5
D 6
Your answer [1]
14 What do curly arrows always show in reaction mechanisms?
A Movement of one electron.
B Movement of a pair of electrons.
C Movement of a lone pair of electrons.
D Movement of the electrons in a covalent bond.
Your answer [1]
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15 Which structural isomer of C7H16 has the weakest induced dipole–dipole interactions (London
forces)?
A 2,3-dimethylpentane
B 3-ethylpentane
C 2-methylhexane
D 2,2,3-trimethylbutane
Your answer [Show Less]