Year :
1987
Title :
Chemistry
Exam :
JAMB Exam
Paper 1 | Objectives
21 - 30 of 34 Questions
| # | Question | Ans |
|---|---|---|
| 21. |
A stream of air was successively passed through three tubes X, Y and Z containing a concentrated aqueous solution of KOH, red hot copper powder and fused calcium chloride respectively. What was the composition of the gas emanating from tube Z? A. CO2 ad ithe inert gases B. N2, CO2 and the inert gases C. N2 and the inert gases D. water vapour, N2 and the inert gases |
C |
| 22. |
In the purification of town water supply, alum is used principally to? A. kill bacteria B. control the pH of water C. improve the taste of the water D. coagulate small pasrticles of mud |
D |
| 23. |
Which of the following water samples will have the highest titre value when titrated for the Ca2+ ions using soap solution? A. Permanently hard water after boiling B. emporarily hard water after boiling C. Rain water stored in a glass jar for two years D. Permanent hard water passed through permuitit |
A |
| 24. |
Oil spillage in ponds and creeks can be cleaned up by? A. burning off the oil layer B. spraying with detergent C. dispersal with compressed air D. spraying with hot water |
B |
| 25. |
The solubility of Na3AsO4(H2O)12 is 38.9g per 100g H2O. What is the mass percentage of Na3AsO4 in the saturated solution? A. 87.27% B. 38.9% C. 19.1% D. 13.7% |
C |
| 26. |
In which of the following are the aqueous solutions of each of the substances correctly arranged in order to decreasing acidity? A. Ethanoic acid, milk or magnesia, sodium chloride, hydrochloric acid and sodium hydroxide B. Ethanoic acid, hydrochloric acid, milk of magnesia, sodium chloride and sodium chloride and sodium hydroxide C. Hydrochloride acid, ethanol acid, sodium chloride, milk of magnesia and sodium hydroxide D. Hydrochloride acid, sodium hydroxide sodium chloride, ethanol acid, and milk of magnesia |
C |
| 27. |
If 24.83 cm3 of 0.15 M NaOH is titrated to its end point with 39.45 cm3 A. 0.094 M B. 0.150 M C. 0.940 M D. 1.500 M Detailed SolutionNaOH + HCl → NaCl + H2O moles ratio = 1/1↔ (MaVa) / Mb x 39.45 = 0.094 |
|
| 28. |
The atomic numbers of two elements X and Y are 12 and 19 respectively. The bond of these two elements is? A. ionic B. covalent C. Metallic D. co-ordinate Detailed Solution- Both elements are Magnesium and Potassium respectively- In general, covalent bonds form between nonmetals, ionic bonds form between metals and nonmetals, and metallic bonds form between metals. |
|
| 29. |
If d represents the density of a gas and K is a constant, the rate of gaseous diffusion r is related to d by the equation? A. r = k/√d B. r = kd C. r =k/d D. r = k √d Detailed Solutionr = k /√d |
|
| 30. |
An isotope has an atomic number of 17 and a mass number of 36. Which of the following gives the correct number of neutrons and protons in an atom of the isotope? A. Neutrons 53, Protons 17 B. Neutrons 17, Protons 36 C. Neutrons 19, Protons 17 D. Neutrons 36, Protons 17 Detailed SolutionMass number = number of protons + number of neutrons36 = 17 + X; X = 36 -17 = 19 19 neutrons and 17 protons |
| 21. |
A stream of air was successively passed through three tubes X, Y and Z containing a concentrated aqueous solution of KOH, red hot copper powder and fused calcium chloride respectively. What was the composition of the gas emanating from tube Z? A. CO2 ad ithe inert gases B. N2, CO2 and the inert gases C. N2 and the inert gases D. water vapour, N2 and the inert gases |
C |
| 22. |
In the purification of town water supply, alum is used principally to? A. kill bacteria B. control the pH of water C. improve the taste of the water D. coagulate small pasrticles of mud |
D |
| 23. |
Which of the following water samples will have the highest titre value when titrated for the Ca2+ ions using soap solution? A. Permanently hard water after boiling B. emporarily hard water after boiling C. Rain water stored in a glass jar for two years D. Permanent hard water passed through permuitit |
A |
| 24. |
Oil spillage in ponds and creeks can be cleaned up by? A. burning off the oil layer B. spraying with detergent C. dispersal with compressed air D. spraying with hot water |
B |
| 25. |
The solubility of Na3AsO4(H2O)12 is 38.9g per 100g H2O. What is the mass percentage of Na3AsO4 in the saturated solution? A. 87.27% B. 38.9% C. 19.1% D. 13.7% |
C |
| 26. |
In which of the following are the aqueous solutions of each of the substances correctly arranged in order to decreasing acidity? A. Ethanoic acid, milk or magnesia, sodium chloride, hydrochloric acid and sodium hydroxide B. Ethanoic acid, hydrochloric acid, milk of magnesia, sodium chloride and sodium chloride and sodium hydroxide C. Hydrochloride acid, ethanol acid, sodium chloride, milk of magnesia and sodium hydroxide D. Hydrochloride acid, sodium hydroxide sodium chloride, ethanol acid, and milk of magnesia |
C |
| 27. |
If 24.83 cm3 of 0.15 M NaOH is titrated to its end point with 39.45 cm3 A. 0.094 M B. 0.150 M C. 0.940 M D. 1.500 M Detailed SolutionNaOH + HCl → NaCl + H2O moles ratio = 1/1↔ (MaVa) / Mb x 39.45 = 0.094 |
|
| 28. |
The atomic numbers of two elements X and Y are 12 and 19 respectively. The bond of these two elements is? A. ionic B. covalent C. Metallic D. co-ordinate Detailed Solution- Both elements are Magnesium and Potassium respectively- In general, covalent bonds form between nonmetals, ionic bonds form between metals and nonmetals, and metallic bonds form between metals. |
|
| 29. |
If d represents the density of a gas and K is a constant, the rate of gaseous diffusion r is related to d by the equation? A. r = k/√d B. r = kd C. r =k/d D. r = k √d Detailed Solutionr = k /√d |
|
| 30. |
An isotope has an atomic number of 17 and a mass number of 36. Which of the following gives the correct number of neutrons and protons in an atom of the isotope? A. Neutrons 53, Protons 17 B. Neutrons 17, Protons 36 C. Neutrons 19, Protons 17 D. Neutrons 36, Protons 17 Detailed SolutionMass number = number of protons + number of neutrons36 = 17 + X; X = 36 -17 = 19 19 neutrons and 17 protons |