Year :
2016
Title :
Chemistry
Exam :
WASSCE/WAEC MAY/JUNE
Paper 1 | Objectives
1 - 10 of 50 Questions
| # | Question | Ans |
|---|---|---|
| 1. |
The following atoms of carbon 126C, 136C and 146C can be described as? A. Allotropes B. Isomers C. Isotopes D. Isotones |
C |
| 2. |
An atom X consist of 6 protons, 6 electrons and 7 neutrons. Which of the following representations of the atom is correct? A. 136X B. 137X C. 196X D. 197X |
A |
| 3. |
How many electron are present in 94Be2+? A. 2 B. 4 C. 5 D. 6 |
A |
| 4. |
When element \(_{20}\)Y combines with element \(_8\)Z, it forms A. A covalent compound , YZ is formed B. A covalent compound, ZY is formed C. An ionic compound, YZ is formed D. An ionic compound, ZY is formed Detailed SolutionY = 2,8,8,2 and Z = 2,6.Y will readily give off its 2 valence electrons and Z will accept the 2 electrons in order to achieve octet configuration. Hence, the compound YZ is formed by ionic bonding. |
|
| 5. |
The boiling points of HF, H2O and NH3 increase in the order of A. NH3 B. H2O < HF C. HF < NH3 < H2O D. NH3 < HF < H2O Detailed SolutionAmmonia = -33.34°C; Hydrogen fluoride = 19.5°C; Water = 100°C |
|
| 6. |
Chemicals that are produced in small quantities and with very degree of purity are A. Bulk chemicals B. Fine chemicals C. Heavy chemicals D. Light chemicals |
B |
| 7. |
The mass of potassium hydroxide required to make 300.ocm3 of 0.4 moldm-3 solution is {KOH = 56.0} A. 26.88g B. 13.44g C. 6.72g D. 3.36g Detailed Solution300cm3 of 0.4moldm31000cm3 contains 0.4mole 300cm3 will contain \(\frac{300 \times 0.4}{1000}\) = 0.12mole Number of moles = \(\frac{Mass}{\text {Molecular mass}}\) Mass = number of moles x m.mass = 0.12 x 56 = 6.72g |
|
| 8. |
Metals can be stretched into wires because they are A. Ductile B. Good conductors C. Lustrous D. Malleable |
A |
| 9. |
Aluminium is used in the manufacture or aircraft because it A. Is hard and brittle B. Is light and resists corrosion C. Has high density and conducts electricity D. Is malleable and ductile |
B |
| 10. |
An unsaturated solution differs from a saturated solution at a given temperature because it A. Cannot dissolve more solute B. Can hold more solute than it can actually dissolve C. Can still dissolve more solute at given temperature D. Form crystal more easily on cooling |
C |
| 1. |
The following atoms of carbon 126C, 136C and 146C can be described as? A. Allotropes B. Isomers C. Isotopes D. Isotones |
C |
| 2. |
An atom X consist of 6 protons, 6 electrons and 7 neutrons. Which of the following representations of the atom is correct? A. 136X B. 137X C. 196X D. 197X |
A |
| 3. |
How many electron are present in 94Be2+? A. 2 B. 4 C. 5 D. 6 |
A |
| 4. |
When element \(_{20}\)Y combines with element \(_8\)Z, it forms A. A covalent compound , YZ is formed B. A covalent compound, ZY is formed C. An ionic compound, YZ is formed D. An ionic compound, ZY is formed Detailed SolutionY = 2,8,8,2 and Z = 2,6.Y will readily give off its 2 valence electrons and Z will accept the 2 electrons in order to achieve octet configuration. Hence, the compound YZ is formed by ionic bonding. |
|
| 5. |
The boiling points of HF, H2O and NH3 increase in the order of A. NH3 B. H2O < HF C. HF < NH3 < H2O D. NH3 < HF < H2O Detailed SolutionAmmonia = -33.34°C; Hydrogen fluoride = 19.5°C; Water = 100°C |
| 6. |
Chemicals that are produced in small quantities and with very degree of purity are A. Bulk chemicals B. Fine chemicals C. Heavy chemicals D. Light chemicals |
B |
| 7. |
The mass of potassium hydroxide required to make 300.ocm3 of 0.4 moldm-3 solution is {KOH = 56.0} A. 26.88g B. 13.44g C. 6.72g D. 3.36g Detailed Solution300cm3 of 0.4moldm31000cm3 contains 0.4mole 300cm3 will contain \(\frac{300 \times 0.4}{1000}\) = 0.12mole Number of moles = \(\frac{Mass}{\text {Molecular mass}}\) Mass = number of moles x m.mass = 0.12 x 56 = 6.72g |
|
| 8. |
Metals can be stretched into wires because they are A. Ductile B. Good conductors C. Lustrous D. Malleable |
A |
| 9. |
Aluminium is used in the manufacture or aircraft because it A. Is hard and brittle B. Is light and resists corrosion C. Has high density and conducts electricity D. Is malleable and ductile |
B |
| 10. |
An unsaturated solution differs from a saturated solution at a given temperature because it A. Cannot dissolve more solute B. Can hold more solute than it can actually dissolve C. Can still dissolve more solute at given temperature D. Form crystal more easily on cooling |
C |