Year :
1989
Title :
Chemistry
Exam :
JAMB Exam
Paper 1 | Objectives
1 - 10 of 49 Questions
| # | Question | Ans |
|---|---|---|
| 1. |
Which of the following would support the conclusion that a solid sample is a mixture? A. the solid can be ground to a fine powder B. the density of the solid is 2.25 g dm3 C. the solid has a melting range of 300oC to 375oC D. the solid absorbs moisture from the atmosphere |
C |
| 2. |
The molar ratio of carbon to hydrogen of a volatile liquid compound is 1: 2. 0. 12 g of the liquid on evaporation at s.t.p. gave 32 cm3 of vapour. The molecular formula of the liquid is A. C 3 H 6 B. C 4H 8 C. C 5C 10 D. C 6H 12 |
D |
| 3. |
20.00 cm 3 of a solution containing 0.53 g of anhydrous Na2CO3 in 100 cm3 requires 25.00 cm3 of H2SO4 for complete neutralisation. The concentration of the acid solution in moles per dm is [H =1, C = 12, O = 16, Na =23, S = 32] A. 0.02 B. 0.04 C. 0.06 D. 0.08 |
B |
| 4. |
The minimum volume of oxygen required for the complete combustion of a mixture of 10cm 3 of CO and 15 cm 3 of H 2 is A. 25.0cm3 B. 12.5 cm3 C. 10.0 cm3 D. 5.0cm3 |
B |
| 5. |
What is the partial pressure of hydrogen gas collected A. 737 mm Hg B. 763 mm Hg C. 777 mm Hg D. 783 mm Hg |
A |
| 6. |
The atomic radius of Li, Na and K are 1: 33A, 1. 54A and 1. 96A res pectively. Which of the following explaqins this gradation in atomic radius? A. electropositivity decreases from Li to Na to K B. electronegativity decreases from Li to Na to K C. the number of the electron shells increases from Li to Na to K D. the elements are in the same period |
C |
| 7. |
Elements X and Y have electronic configurations 1s\(^2\)2s\(^2\)2p\(^4\) and 1s\(^2\)2s\(^2\)2p\(^2\)3s\(^6\)3p\(^1\) respectively. When they combine, the formula of the compound formed is? A. XY B. YX C. X2Y3 D. Y2X3 Detailed Solution\(\frac{\text{Element X}}{1s^22s^21p^4}\)Valency of X is 2 \(\frac{\text{Element Y}}{1s^22s^22p^63s^23P^1}\) valency of Y is 3 There is an exchange of valency when a compound is being formed. Hence, we have Y\(_2\)X\(_3\) |
|
| 8. |
The atomic number of caesium is 55 and its atomic mass is 133. The nucleus of caesium atom therefore contains A. 78 protons and 55 elections B. 55 protons and 78 neutrons C. 55 neutrons 78 electrons D. 78 protons and 55 neutrons |
B |
| 9. |
Four elements P,Q, R and S have atomic numbers of 4, 10, 12 and 14 respectively . Which of these electrons is a noble gas? A. P B. Q C. R D. S |
B |
| 10. |
How many valence electrons are contained in the element represented 3115P? A. 3 B. 5 C. 15 D. 31 |
B |
| 1. |
Which of the following would support the conclusion that a solid sample is a mixture? A. the solid can be ground to a fine powder B. the density of the solid is 2.25 g dm3 C. the solid has a melting range of 300oC to 375oC D. the solid absorbs moisture from the atmosphere |
C |
| 2. |
The molar ratio of carbon to hydrogen of a volatile liquid compound is 1: 2. 0. 12 g of the liquid on evaporation at s.t.p. gave 32 cm3 of vapour. The molecular formula of the liquid is A. C 3 H 6 B. C 4H 8 C. C 5C 10 D. C 6H 12 |
D |
| 3. |
20.00 cm 3 of a solution containing 0.53 g of anhydrous Na2CO3 in 100 cm3 requires 25.00 cm3 of H2SO4 for complete neutralisation. The concentration of the acid solution in moles per dm is [H =1, C = 12, O = 16, Na =23, S = 32] A. 0.02 B. 0.04 C. 0.06 D. 0.08 |
B |
| 4. |
The minimum volume of oxygen required for the complete combustion of a mixture of 10cm 3 of CO and 15 cm 3 of H 2 is A. 25.0cm3 B. 12.5 cm3 C. 10.0 cm3 D. 5.0cm3 |
B |
| 5. |
What is the partial pressure of hydrogen gas collected A. 737 mm Hg B. 763 mm Hg C. 777 mm Hg D. 783 mm Hg |
A |
| 6. |
The atomic radius of Li, Na and K are 1: 33A, 1. 54A and 1. 96A res pectively. Which of the following explaqins this gradation in atomic radius? A. electropositivity decreases from Li to Na to K B. electronegativity decreases from Li to Na to K C. the number of the electron shells increases from Li to Na to K D. the elements are in the same period |
C |
| 7. |
Elements X and Y have electronic configurations 1s\(^2\)2s\(^2\)2p\(^4\) and 1s\(^2\)2s\(^2\)2p\(^2\)3s\(^6\)3p\(^1\) respectively. When they combine, the formula of the compound formed is? A. XY B. YX C. X2Y3 D. Y2X3 Detailed Solution\(\frac{\text{Element X}}{1s^22s^21p^4}\)Valency of X is 2 \(\frac{\text{Element Y}}{1s^22s^22p^63s^23P^1}\) valency of Y is 3 There is an exchange of valency when a compound is being formed. Hence, we have Y\(_2\)X\(_3\) |
|
| 8. |
The atomic number of caesium is 55 and its atomic mass is 133. The nucleus of caesium atom therefore contains A. 78 protons and 55 elections B. 55 protons and 78 neutrons C. 55 neutrons 78 electrons D. 78 protons and 55 neutrons |
B |
| 9. |
Four elements P,Q, R and S have atomic numbers of 4, 10, 12 and 14 respectively . Which of these electrons is a noble gas? A. P B. Q C. R D. S |
B |
| 10. |
How many valence electrons are contained in the element represented 3115P? A. 3 B. 5 C. 15 D. 31 |
B |