JAMB Chemistry Past Questions (2005)
Q1. When sulphur (IV) oxide is passed into a solution of sodium hydroxide for a long time. It eventually produces a solution of
A. Na2SO4
B. NaHSO4
C. Na2SO3
D. NaHSO3
Answer: D
Q2. Kerosene is commonly used to remove the red colour stain of palm oil from clothes because it
A. Helps to spread the oil over a larger surface area
B. Makes the oil evaporate easily by dissolving it
C. Helps to dilute the oil and reduce its colour
D. Reacts with the oil to form an odourless compound
Answer: B
Q3. The component of an atom that contributes least to its mass is the
A. Nucleus
B. Neutron
C. Electron
D. Proton
Answer: C
Q4. The density of a certain gas is 1.98g dm-3 at s.t.p. What is the molecular mass of the gas [Molar volume of a gas at s.t.p = 22.4dm-3]
A. 26.0g
B. 31.0g
C. 54.0g
D. 44.0g
Answer: D
Q5. In a flame test for calcium, the flame appears
A. Blue when viewed through a blue glass
B. Green when viewed through a blue glass
C. Orange-red when viewed through a blue glass
D. Brick-red when viewed through a blue glass
Answer: C
Q6. What will happen if an aluminum spoon is used to stir a solution of iron (II) trioxonitrate(V)
A. The spoon will be reduced while the iron(II) ions will be oxidized
B. The spoon will be oxidized while the iron (II) ions will be reduced to the metal
C. The spoon will be reduced
D. The spoon will increase in size
Answer: B
Q7. Which of these properties gives a solid its definite shape
A. Weak intermolecular attraction
B. High boiling point
C. High melting point
D. Strong intermolecular attraction
Answer: D
Q8. The decolourization of the purple colour of a tetraoxomanganate (VII) ion is a test for
A. Alkanals
B. Alkanes
C. Alkenes
D. Alkanols
Answer: C
Q9. How many hydrogen atoms does a single ring cycloalkane have less than the corresponding open- chain alkane
A. Three
B. One
C. Four
D. Two
Answer: D
Q10. 25cm3 of a mixture of noble gases was obtained from air after the removal of other constituents. What was the original volume of air
A. 125cm3
B. 1250cm3
C. 2500cm3
D. 80cm3
Answer: C
Q11. In which of the following reactions can the oxidation number of nitrogen be said to have increased
A. FeSO4(aq) + NO(g) → Fe(NO)SO4(S)
B. 2NO(g) + O2(g) → 2NO2(g)
C. NO(g) + CI2(g) → NOCI2(l)
D. NO(g) + Br2(l) → NOBr2(l)
Answer: B
Q12. NH4CI(g) ⇌ NH3(g) + HCI(g) The reaction above can only attain equilibrium if
A. It is in a closed system
B. It is in an open system
C. One of the products is removed
D. A gaseous reactant is added
Answer: A