CHEMISTRY

4.
Which of the following diagrams best
represents the arrangement of electron pairs
around the central iodine atom in the I
3
–
ion?
A
B
C
D
5.
When a voltage is applied to an n-type
semiconductor, which of the following migrate
through the lattice?
A Electrons
B Negative ions
C Positive holes
D Both electrons and positive holes
6.
Which of the following compounds would
produce fumes of hydrogen chloride when
added to water?
A LiCl
B MgCl
2
C PCl
3
D CCl
4
Page three
[X012/701]
[Turn over
1.
The diagram shows one of the series of lines in
the hydrogen emission spectrum.
Each line
A represents an energy level within a
hydrogen atom
B results from an electron moving to a
higher energy level
C lies within the visible part of the
electromagnetic spectrum
D results from an excited electron dropping
to a lower energy level.
2.
Which of the following compounds shows
most covalent character?
ACH
4
B NaH
CNH
3
DPH
3
3.
In which of the following species is a dative
covalent bond present?
AH
3
O
+
BH
2
O
COH
–
DO
2
121
.
6 102
.
697
.
391
.
2
wavelength (nm)

11.
Which of the following graphs shows the
temperature change as 2 mol l
–1
sodium
hydroxide is added to 25 cm
3
of 2 mol l
–1
hydrochloric acid?
A
B
C
D
7.
Zinc oxide reacts as shown.
ZnO(s)
+
2HCl(aq)
?
ZnCl
2
(aq) + H
2
O(
A
)
ZnO(s)
+
2NaOH(aq) + H
2
O(
A
)
?
Na
2
Zn(OH)
4
(aq)
This shows that zinc oxide is
A basic
B acidic
C neutral
D amphoteric.
8.
The correct formula for the
tetraamminedichlorocopper(II) complex is
A [Cu(NH
3
)
4
Cl
2
]
2
–
B [Cu(NH
3
)
4
Cl
2
]
C [Cu(NH
3
)
4
Cl
2
]
2
+
D [Cu(NH
3
)
4
Cl
2
]
4
+
.
9.
Which of the following aqueous solutions
contains the
greatest
number of
negatively
charged ions?
A 500 cm
3
0
.
10 mol l
–1
Na
2
SO
4
(aq)
B 250 cm
3
0
.
12 mol l
–1
BaCl
2
(aq)
C 300 cm
3
0
.
15 mol l
–1
KI(aq)
D 400 cm
3
0
.
10 mol l
–1
Zn(NO
3
)
2
(aq)
10.
When one mole of phosphorus pentachloride
was heated to 523 K in a closed vessel, 50%
dissociated as shown.
How many moles of gas were present in the
equilibrium mixture?
A0
.
5
B1
.
0
C1
.
5
D2
.
0
Page four
[X012/701]
U
532
PCl (g) PCl (g) + Cl (g)
02550
Volume of NaOH/cm
3
Temperature/ºC
02550
Volume of NaOH/cm
3
Temperature/ºC
02550
Volume of NaOH/cm
3
Temperature/ºC
02550
Volume of NaOH/cm
3
Temperature/ºC

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Please don’t apply if you don’t have M.A. in chemistry.