Year :
2004
Title :
Chemistry
Exam :
JAMB Exam
Paper 1 | Objectives
11 - 20 of 50 Questions
| # | Question | Ans |
|---|---|---|
| 11. |
The property of chlorine which causes hydrogen chloride to be more ionic than the chlorine molecules is its A. electrovalency B. electron affinity C. electropositivity D. electronegativity |
D |
| 12. |
Chlorine consisting of two isotopes of mass number 35 and 37 in the ratio 3:1 has an atomic mass of 35.5. Calculate the relative abundance of the isotopes of mass number 37 A. 20 B. 25 C. 60 D. 75 Detailed SolutionLet the relative abundance of oxygen with mass 37 be x%∴ The relative abundance of the isotope of mass 35 = (100 - x)%. Total mass of isotopes of mass 37 = 37x, while that of 35 = 35(100 - x) ∴ Total mass of the 100 atoms = 37x + 35(100 - x) = 35.5 = 37x + 3500 - 35x = 35.5 ∴ Mean mass of chlorine atom = (2x + 3500)/100 = 35.5 2x + 3500 = 3550; x = 50/2 = 25 |
|
| 13. |
Which of the following mixture of gases is likely to burn in flame A. neon and hydrogen B. nitrogen and helium C. helium and neon D. neon and nitrogen |
A |
| 14. |
Hardness of water is caused by the presence of ions of A. magnesium and silver B. cacium and magnesium C. sodium and potassium D. calcium and sodium |
B |
| 15. |
Pollution of underground water by metal ions is very likely in the soil that has high A. acidity B. alkalinity C. chloride content D. nitrate content Detailed SolutionTrioxonitrate(v) salts are generally d only soluble salts of some metals.All trioxonitrate(v) salts r soluble in water. Therefore d metal ions found in underground water, are derived mostly 4rm d soluble nitrates (Trioxonitrate(v) salts) of those metals. |
|
| 16. |
A carcinogenic substance is A. asbestos dust B. sawdust C. nitrogen (II) oxide D. carbon (II) oxide |
A |
| 17. |
The solubility in mol dm/-3 of 20g of CuSO4 dissolved in 100g of water at 180o is A. 0.13 B. 0.25 C. 1.25 D. 2.00 Detailed SolutionRelative molecular mass of CuSO4 = 64 + 32 + 16 * 4 = 160The number of moles of CUSO4 = reacting mass/molecular mass = 20/160 = 0.125 100g of water dissolved 0.125m of CuSO4 100g of water will dissolve (0.125 * 1000)/100 = 1.25mol dm3 |
|
| 18. |
Calcium tetraoxosulphate (VI) dissolves in water only sparingly to form a A. solution B. suspension C. precipitate D. colloid |
C |
| 19. |
Which of the following compound is a normal salt? A. NaHS B. NaHSO4 C. NaHCO3 D. Na2CO3 |
D |
| 20. |
What volume of 0.5 mol dm-3 H2SO4 will exactly neutralize 20cm3 of 0.1 mol dm-3 NaOH solution? A. 2.0 cm3 B. 5.0 cm3 C. 6.8 cm3 D. 8.3 cm3 Detailed Solution2NaOH + H2SO4 → Na2SO4 + 2H2OCaVa/CbVb = ratio of acid/ratio of base (0.5 * Va)/(0.1 * 20) = 1/2 ∴ Va = 2.0cm |
| 11. |
The property of chlorine which causes hydrogen chloride to be more ionic than the chlorine molecules is its A. electrovalency B. electron affinity C. electropositivity D. electronegativity |
D |
| 12. |
Chlorine consisting of two isotopes of mass number 35 and 37 in the ratio 3:1 has an atomic mass of 35.5. Calculate the relative abundance of the isotopes of mass number 37 A. 20 B. 25 C. 60 D. 75 Detailed SolutionLet the relative abundance of oxygen with mass 37 be x%∴ The relative abundance of the isotope of mass 35 = (100 - x)%. Total mass of isotopes of mass 37 = 37x, while that of 35 = 35(100 - x) ∴ Total mass of the 100 atoms = 37x + 35(100 - x) = 35.5 = 37x + 3500 - 35x = 35.5 ∴ Mean mass of chlorine atom = (2x + 3500)/100 = 35.5 2x + 3500 = 3550; x = 50/2 = 25 |
|
| 13. |
Which of the following mixture of gases is likely to burn in flame A. neon and hydrogen B. nitrogen and helium C. helium and neon D. neon and nitrogen |
A |
| 14. |
Hardness of water is caused by the presence of ions of A. magnesium and silver B. cacium and magnesium C. sodium and potassium D. calcium and sodium |
B |
| 15. |
Pollution of underground water by metal ions is very likely in the soil that has high A. acidity B. alkalinity C. chloride content D. nitrate content Detailed SolutionTrioxonitrate(v) salts are generally d only soluble salts of some metals.All trioxonitrate(v) salts r soluble in water. Therefore d metal ions found in underground water, are derived mostly 4rm d soluble nitrates (Trioxonitrate(v) salts) of those metals. |
| 16. |
A carcinogenic substance is A. asbestos dust B. sawdust C. nitrogen (II) oxide D. carbon (II) oxide |
A |
| 17. |
The solubility in mol dm/-3 of 20g of CuSO4 dissolved in 100g of water at 180o is A. 0.13 B. 0.25 C. 1.25 D. 2.00 Detailed SolutionRelative molecular mass of CuSO4 = 64 + 32 + 16 * 4 = 160The number of moles of CUSO4 = reacting mass/molecular mass = 20/160 = 0.125 100g of water dissolved 0.125m of CuSO4 100g of water will dissolve (0.125 * 1000)/100 = 1.25mol dm3 |
|
| 18. |
Calcium tetraoxosulphate (VI) dissolves in water only sparingly to form a A. solution B. suspension C. precipitate D. colloid |
C |
| 19. |
Which of the following compound is a normal salt? A. NaHS B. NaHSO4 C. NaHCO3 D. Na2CO3 |
D |
| 20. |
What volume of 0.5 mol dm-3 H2SO4 will exactly neutralize 20cm3 of 0.1 mol dm-3 NaOH solution? A. 2.0 cm3 B. 5.0 cm3 C. 6.8 cm3 D. 8.3 cm3 Detailed Solution2NaOH + H2SO4 → Na2SO4 + 2H2OCaVa/CbVb = ratio of acid/ratio of base (0.5 * Va)/(0.1 * 20) = 1/2 ∴ Va = 2.0cm |