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DAY 4: JAMB UTME CHEMISTRY 2020 QUESTIONS.
1. The periodic classification of the elements is an arrangement of the elements in order of their
A. atomic weights
B. isotopic weights
C. molecular weights
D. atomic numbers
2. If 1 litre of 2.2M sulphuric acid is poured into a bucket containing 10 litres of water, and the resulting solution mixed thoroughly, the resulting sulphuric acid concentration will be
A. 2.2 M
B. 1.1 M
C. 0.22 M
D. 0.11 M
In the above experiment (Fig. 1) the litmus paper will initially
A. be bleached
B. turn green
C. turn red
D. turn blue
4. A correct electrochemical series can be obtained from K, Na, Ca, Al, Mg. Zn, Fe,
Pb, H, Cu, Hg, Ag, Au by interchanging
A. Al and Mg
B. Zn and Fe
C. Zn and Pb
D. Pb and H
5. A basic postulate of the kinetic theory of gases is that the molecules of a gas move in straight lines between collisions. This implies that
A. collisions are perfectly elastic
B. forces of repulsion exist
C. forces of repulsion and attraction are in equilibrium
D. collisions are inelastic.
6. On which of the following is the solubility of a gaseous substance dependent?
I. Nature of solvent
II. Nature of solute
A. I, II, III and IV
B. I and II only
C. II only
D. I, III and IV only.
7. Which of the following statements is correct about the periodic table?
A. Elements in the same period have the same number of valence electrons
B. The valence electrons of the elements in the same period increase progressively across the period.
C. Elements in the same group have the same number of electron shells
D. The non-metallic properties of the elements tend to decrease across each period.
8. The boiling of fat and aqueous caustic soda is referred to as
9. Which of the following pairs of substances will react further with oxygen to form a higher oxide?
A. CO2 and H2O
B. NO and H2O
C. CO and CO2
D. SO2 and NO
10.In the preparation of oxygen by heating KCIO3 in the presence of MnO2, only moderate heat is needed because the catalyst acts by
A. lowering the pressure of the reaction
B. increasing the surface area of the reaction
C. increasing the rate of the reaction
D. lowering the energy barrier of the reaction.
11. Methanoic acid mixes with water in all proportions and has about the same boiling point as water. Which of the following methods would you adopt to obtain pure water from a mixture of sand, water and methanoic acid?
A. Fractional distillation
B. Filtration followed by distillation
C. Neutralization with sodium hydroxide followed by distillation
D. Neutralization with sodium hydroxide followed by filtration
12.A quantity of electricity liberates 3.6 g of silver from its salt. What mass of aluminum will be liberated from its salt by the same quantity of electricity?
A. 2.7 g
B. 1.2 g
C. 0.9 g
D. 0.3 g
[Al = 27, Ag = 108].
13.Suitable reagents for the laboratory preparation of nitrogen are
A. sodium dioxonitrate (III) and ammonium chloride
B. sodium trioxonitrate (V) and ammonium chloride
C. sodium chloride and ammonium trioxonitrate (V)
D. sodium chloride and ammonium diozonitrate (III).
14. The number of electrons in the valence shell of an element of atomic number 14 is
15. What volume of oxygen will remain after reacting 8cm3 of hydrogen gas with 20cm3 of oxygen gas?
16. If one of the following oxides is heated with hydrogen or carbon using a Bunsen
burner, it is not reduced to the metal. Which one is it?
A. lead oxide
B. Magnesium oxide
C. Copper oxide
D. Tin oxide
17.The name for
A. 1 -methylpentane
D. 1 -dimethylpropane
18. An aqueous solution of a metal salt M, gives a white precipitate with NaOH which dissolves in excess NaOH. With aqueous ammonia, the solution of M also gives a white precipitate which dissolves in excess ammonia. Therefore, the cation in M is
19.What is the concentration of a solution containing 2g of NaOH in 100cm3 of solution?
A. 0.40 mol dm-3
B. 0.50 mol dm-3
C. 0.05 mol dm-3
D. 0.30 mol dm-3
[Na = 23, O =16, H =1]
20.How many atoms are present in 6.0g, of magnesium?
A. 1.20 × 1022
B. 2.41 × 1022
C. 1.51 × 1023
D. 3.02 × 1023
[Mg =24, NA = 6.02 × 1023 mol-1].
21.The radio isotope used in industrial radiography for the rapid checking of faults in welds and casting is
A. carbon – 14
B. Phosphorus – 32
D. Iodine – 131
22. Beryllium and Aluminium have similar properties because they
A. are both metals
B. belong to the same group
C. belong to the same period
D. are positioned diagonally to each other
23.mE + Nf ⇋ pG + qH
In the equation above, the equilibrium constant is given by
24.(i) 3CuO(s) + 2NH3(g) ⇋ 3Cu(s) + 3H2O(l)+ N2(g)
(ii) 2NH3(g) + 3CI2(g) ⇋ 6HCI(g) + N2(g)
(iii) 4NH3(g) + 3O2(g) ⇋ 6H2O(l) + 2N2(g).
The reactions represented by the equations above demonstrate the
A. basic properties of ammonia
B. acidic properties of ammonia
C. reducing properties of ammonia
D. oxidizing properties of ammonia
25. The salt that reacts with dilute hydrochloric acid to produce a pungent smelling gas which decolourizes acidified purple potassium tetraoxomanganate(VII) solution is
26.The refreshing and characteristic taste of soda water and other soft drinks is as a
result of the presence in them of
A. carbon (IV) oxide
B. carbon (II) oxide
27.Which of the following are mixtures?
ii. Rubber latex.
iii. Vulcanizer’s solution
iv. Carbon (II)sulphide
A. i, ii and iii
B. i, ii and iv
C. i and ii only
D. i and iv.
28.A balanced chemical equation obeys the law of
A. conservation of mass
B. definite proportions
C. multiple proportions
D. conservation of energy
29.A given amount of gas occupies 10.0dm3 at 4 atm and 273°C. The number of moles of the gas present is
A. 0.89 mol
B. 1.90 mol
C. 3.80 mol
D. 5.70 mol
[Molar volume of a gas at stp. = 22.4dm3]
30. According to Charles’ law, the volume of a gas becomes zero at
31. A substance that is used as a ripening agent for fruits is
32. The Sulphide which is insoluble in dilute hydrochloric acid is
33. What is the pH of 0.001 moldm-3solution of the sodium hydroxide?
34. The type of bonding in [Cu(NH3)4]2+ is
35. Which of the following is an example of a chemical change?
A. dissolution of salt in water
B. rusting of iron
C. melting of ice
D. separating a mixture by distillation
36. To what temperature must a gas at 273K be heated in order to double both its volume and pressure?
37. According to the Kinetic Theory, an increase in temperature causes the kinetic energy of particles to:
C. be zero
D. remain constant
38. An element used in the production of matches is
39. Which of the following gases may not be dried with concentrated sulphuric acid?
40. Consecutive members of an alkane homologous series differ by
DAY 4:MATHEMATICS ANSWER
1 -12 (or polygon havn 150deg)
2 – x>4
3 – (2,10,14,22,26)
4 – 2y-3x)(y-6x)
5 – 12 (x varies directly….)
6 – 345
7 – 6 (if x 1 is a factor)
8 – 187
9 – 10squa3cm
10 – 36
11 – 7!
12 – x<-8
13 – -12cos(-4x)
14 – 42/3
15 – 4piecm
16 – 4-root6
17 – (2 1 -1 -2)
18 – 2x 1/2x-1/2
19 – x y
20 – 34 tonnes
21 – root 6
22 – 3/2 (finding d gradient P(5,6) and Q(3,3)
23 – 9.0%
24 – 10 (regular polygon sides wit 1350)
25 – 5 (finding median)
26 – 20cm
27 – 1/5
28 – 80%
29 – -1/4cos4x c
30 – -2
31 – 1 (for binary operation)
32 – 1232base4
33 – 7 (for y= x2-3x 4…)
34 – 6 (for scores of ten student..)
35 – -4<x<-1
36 – -3 (for gradient of (x,4)and (1,2)…)
37 – 28 (for 110001base2-x10)
38 – 16 (for distribution table of ages
39 – 4whole number 1 over 3
40 – 37.5