Mock Test-Practice Questions 1 [29 marks]
1. [Maximum mark: 1] EXM.1A.SL.TZ0.1
Which of the following is most likely to be a transition metal?
[1]
2. [Maximum mark: 1] EXM.1A.SL.TZ0.2
Which of the following is the correct skeletal formula of butanoic acid?
[1]
3 [Maximum mark: 1] EXM 1A SL TZ0 3
3. [Maximum mark: 1] EXM.1A.SL.TZ0.3
Which is the correct structural formula of this compound?
A. OCOCH2CH3
B. HCOOC2H5
C. HCOOCH2CH3
D. OCOHC2CH3 [1]
4. [Maximum mark: 15] EXM.1B.HL.TZ0.2
Broccoli is a rich source of ascorbic acid (vitamin C). To investigate the
importance of storage temperature of ascorbic acid, a sample of broccoli was
stored at different temperatures, from 5 °C (refrigerator temperature) to 75 °C at
10 °C intervals. A simple colourimetric method based on the reaction of
colourless ascorbic acid, AA with a reagent, R, that produces a coloured complex,
AAR, was used to measure the ascorbic acid content.
AA (aq) + R (aq) → AAR (aq)
colourless purple
(a) A calibration curve with pure ascorbic acid and appropriate
amounts of the reagent, R, was prepared by dilutions with
water of an initial aqueous solution of 100 μg/cm−3 ascorbic
acid in water, AA (aq)
(a.i) Calculate the volumes of pure ascorbic acid solution required
for each point of the calibration curve; point 4 of the curve is
shown as an example.
[2]
(a.ii) The resulting calibration curve is shown:
Suggest a range of absorbance values for which this curve can
be used to calculate ascorbic acid of broccoli accurately. [1]
(a.iii) Suggest what should be used as a blank for spectrophotometric
reading. [1]
(a.iv) Discuss why it is important to obtain a value of R2 close to 1 for
a calibration curve. [2]
(b) After 3 days, the broccoli samples were removed from storage
and 1.0 g of each sample was blended with 100.0 cm3 of water.
The filtered solution was mixed with the reactant in the same
proportions as that used for the calibration curve in a cuvette
and measured.
(b.i) The sample stored at 5 °C showed an absorbance of 0.600.
Determine the concentration of ascorbic acid in the sample
solution by interpolation and using the line equation.
interpolation in graph:
..........................................................................................................................
using line
equation: ............................................................................................................................. [2]
(b.ii) Suggest which of the two methods will provide a more accurate
value. [1]
(c) Suggest why water was chosen to extract ascorbic acid from the
spinach leaves with reference to its structure. [2]
(d) The content of ascorbic acid in broccoli was calculated in mg
per 100 g of broccoli for all values of temperature and plotted.
(d.i) Estimate the % change in ascorbic acid concentration when
stored for 3 days storage at 5 °C and 20 °C. [1]
(d.ii) Estimate how much ascorbic acid will remain after 6 days
storage at 20 °C in the same experimental conditions, stating
any assumption made for the calculation. [3]
5. [Maximum mark: 1] EXM.2.HL.TZ0.1
The transition metal copper, Cu, is used in electrical circuits given its
high electrical conductivity. Outline why it is preferred over s- and p-
block metals. [1]
6. [Maximum mark: 1] 23N.1A.SL.TZ1.2
Metal M reacts with 16.0 g of sulfur to produce 26.0 g of the compound
MS2. What is the relative atomic mass of M?
A. 5
B. 10
C. 20
D. 40
[1]
7. [Maximum mark: 1] 23N.1A.SL.TZ1.5
Gallium (Ar = 69.72) consists of two stable isotopes, Ga-69 and Ga-71.
What is the relative abundance of Ga-71?
A. 36 %
B. 40 %
C. 60 %
D. 64 % [1]
8. [Maximum mark: 1] 23N.1A.SL.TZ1.6
Which electron configuration represents a d‑block element in the
ground state?
A. 1s22s22p63s23p64s13d1
B. 1s22s22p63s23p64s13d10
C. 1s22s22p63s23p64s23d9
D. 1s22s22p63s23p64s13d104p1 [1]
9. [Maximum mark: 1] 23N.1A.SL.TZ1.7
A beam containing two different kinds of particles is passed through
oppositely charged plates with the results shown in the diagram.
What conclusion can be drawn from this observation?
A. Particle 1 has a larger mass than particle 2.
B. Particle 2 has a larger mass than particle 1.
C. Particle 1 is positively charged.
[1]
D. Particle 2 is positively charged.
10. [Maximum mark: 1] 23N.1A.SL.TZ1.8
Which factor generally increases when first ionization energy
increases?
A. Atomic radius
B. Electronegativity
C. Metallic character
D. Nuclear charge [1]
11. [Maximum mark: 1] 23N.1A.SL.TZ1.9
The periodic table provided shows 118 elements. Which group of
elements would a new element with atomic number 119 be most
similar to?
A. Alkali metals
B. Halogens
C. Lanthanoids and actinoids
D. Noble gases [1]
12. [Maximum mark: 1] 23N.1A.SL.TZ1.12
What are the electron domain and molecular geometries of SO3?
[1]
13. [Maximum mark: 1] 19M.1A.SL.TZ1.6
Which describes an atom of bismuth, Bi (Z = 83)?
[1]
14. [Maximum mark: 1] 19M.1A.SL.TZ2.5
Which of the following transitions in the hydrogen atom emits the
least energy?
A. n = 2 to n = 1
B. n = 3 to n = 1
C. n = 4 to n = 2
D. n = 4 to n = 3
[1]
15. [Maximum mark: 1] 19M.1A.HL.TZ1.5
Which element is represented by the first eight successive ionization
energies on the graph?
A. Mg
B. S
C. Cl
D. Ar [1]
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