Year :
1992
Title :
Chemistry
Exam :
JAMB Exam
Paper 1 | Objectives
1 - 10 of 51 Questions
| # | Question | Ans |
|---|---|---|
| 1. |
There is a large temperature interval between the melting point and the boiling point of a metal because? A. metals have very high melting points B. metals conduct heat very repaidly C. melting does not break the metalic bond but boiling does D. the crystal lattice of metals is easily broken |
A |
| 2. |
How many moles of (H+) are there in 1 dm3 of 0.5 M solution of H2SO4? A. 2.0 moles B. 1.0 moles C. 0.5 mole D. 0.25 mole Detailed Solutionmole = (M x V ) / (1000cm3) = (0.5 x 1000cm3) = 0.5 molesFor H2SO4 → 2H+SO42- 1 mole of H+ = 0.5 moles 2H+ = 2 x 0.5 mole = 1.0 mole |
|
| 3. |
WH2SO4 + xAI(OH)3 → yH2O + = zAI2(SO4)3. The respective values of w.x.y and z in the equation above are? A. 2,2,5 and 1 B. 3,2,5 and 2 C. 3,2,6 and 1 D. 2,2,6 and 2 |
C |
| 4. |
A given mass of gas occupies 2 dm3 at 300k. At what temperature will its volume be doubled keeping the pressure constant? A. 400 k B. 480 k C. 550 k D. 600 k |
D |
| 5. |
Which of the following is a measure of the average kinetic energy of the molecules of a substance? A. Volume B. Mass C. pressure from age grades D. Temperature |
D |
| 6. |
If 100 cm3 of oxygen pass through a porous plug in 50 seconds, the time taken for the same volume of hydrogen to pass through the same porous plug is? A. 10.0 s B. 12.5 s C. 17.7 s D. 32.0 s Detailed Solution100 cm3 of O2 diffuse 50 sec∴ 100 cm3 of H2 → (100) / (100) x (50) /(1) t1 50 sec molecular mass H+ → 2 x 1 = 2 molecular mass of O2 16 x 2 = 32 T2 = t1 √M2/M1 = t2 = 50 √2/32 50√0.625 = 50 x 0.25 = 12.5 secs |
|
| 7. |
An increase in temperature causes an increase in pressure of a gas in a fixed volume due to an increase in the? A. number of molecules of the gas B. density of the gas molecules C. number of collisions between the gas molecules D. number of collisions between the gas molecules and the walls of the container |
D |
| 8. |
The nucleus of the isotope tritium, contains? A. two neutrons with no protons B. one neutron and one protons C. two neutrons and one proton D. two neutrons, one proton and one electron |
C |
| 9. |
How many lone pairs of electron are there on the central atom of the H2O molecules? A. 1 B. 2 C. 3 D. 4 Detailed SolutionRef___GoogleThe electron-dot structure of NH 3 places one pair of non-bonding electrons in the valence shell of the nitrogen atom. This means that there are three bonded atoms and one lone pair for a coordination number of four around the nitrogen, the same as occurs in H 2O. |
|
| 10. |
147N + X → 178O + 11 H. In the above reaction, X is a? A. neutron B. helium atom C. litgium atom D. deuterium atom |
B |
| 1. |
There is a large temperature interval between the melting point and the boiling point of a metal because? A. metals have very high melting points B. metals conduct heat very repaidly C. melting does not break the metalic bond but boiling does D. the crystal lattice of metals is easily broken |
A |
| 2. |
How many moles of (H+) are there in 1 dm3 of 0.5 M solution of H2SO4? A. 2.0 moles B. 1.0 moles C. 0.5 mole D. 0.25 mole Detailed Solutionmole = (M x V ) / (1000cm3) = (0.5 x 1000cm3) = 0.5 molesFor H2SO4 → 2H+SO42- 1 mole of H+ = 0.5 moles 2H+ = 2 x 0.5 mole = 1.0 mole |
|
| 3. |
WH2SO4 + xAI(OH)3 → yH2O + = zAI2(SO4)3. The respective values of w.x.y and z in the equation above are? A. 2,2,5 and 1 B. 3,2,5 and 2 C. 3,2,6 and 1 D. 2,2,6 and 2 |
C |
| 4. |
A given mass of gas occupies 2 dm3 at 300k. At what temperature will its volume be doubled keeping the pressure constant? A. 400 k B. 480 k C. 550 k D. 600 k |
D |
| 5. |
Which of the following is a measure of the average kinetic energy of the molecules of a substance? A. Volume B. Mass C. pressure from age grades D. Temperature |
D |
| 6. |
If 100 cm3 of oxygen pass through a porous plug in 50 seconds, the time taken for the same volume of hydrogen to pass through the same porous plug is? A. 10.0 s B. 12.5 s C. 17.7 s D. 32.0 s Detailed Solution100 cm3 of O2 diffuse 50 sec∴ 100 cm3 of H2 → (100) / (100) x (50) /(1) t1 50 sec molecular mass H+ → 2 x 1 = 2 molecular mass of O2 16 x 2 = 32 T2 = t1 √M2/M1 = t2 = 50 √2/32 50√0.625 = 50 x 0.25 = 12.5 secs |
|
| 7. |
An increase in temperature causes an increase in pressure of a gas in a fixed volume due to an increase in the? A. number of molecules of the gas B. density of the gas molecules C. number of collisions between the gas molecules D. number of collisions between the gas molecules and the walls of the container |
D |
| 8. |
The nucleus of the isotope tritium, contains? A. two neutrons with no protons B. one neutron and one protons C. two neutrons and one proton D. two neutrons, one proton and one electron |
C |
| 9. |
How many lone pairs of electron are there on the central atom of the H2O molecules? A. 1 B. 2 C. 3 D. 4 Detailed SolutionRef___GoogleThe electron-dot structure of NH 3 places one pair of non-bonding electrons in the valence shell of the nitrogen atom. This means that there are three bonded atoms and one lone pair for a coordination number of four around the nitrogen, the same as occurs in H 2O. |
|
| 10. |
147N + X → 178O + 11 H. In the above reaction, X is a? A. neutron B. helium atom C. litgium atom D. deuterium atom |
B |