Chemistry, 2008, JAMB Exam, Exam, Paper 1 | Objectives

Paper Info

Year :

2008

Title :

Chemistry

Exam :

JAMB Exam

Paper 1 | Objectives

1 - 10 of 49 Questions

#	Question	Ans
1.	Chlorophyll obtained from given leaves of plant can be shown to be composed of more than one coloured component by the technique of A. crystallization B. hydrolysis C. chromatography D. sublimation	C
2.	In countries where the temperature falls below 273K, salt is always sprinkled on the icy road in order to A. lower the melting point of the ice B. increase the density of the ice C. make the ice impure D. raise the melting point of the ice	A
3.	2Na_(s) + 2H₂O_(l) → 2NaOH_(aq) + H_2(g) From the equation above, calculate the mass of sodium hydroxide produced by 2.3g of sodium. [H = 1, O = 16, Na = 23] A. 0.40g B. 0.80g C. 4.00g D. 8.00g Show Content Detailed Solution 2Na_(s) + 2H₂O_(l) → 2NaOH_(aq) + H_2(g) Relative molecular mass of NaOH = 23 + 16 + 1 = 40smol^-1 2 * 23g of sodium react with water to produce 2 * 40g of NaOH ∴ 2.3g of sodium will react with water to produce (2.3 * 40 * 2)/(23 * 2) = 4.00g	C
4.	16.8 g of sodium hydrogen trioxocarbonate (IV) is completely decomposed by heat. Calculate the volume of carbon(IV) oxide given off s.t.p [Na 23, C = 12, O = 16, H = 1, Molar volume of a gas at s.t.p = 22.4 dm³] A. 22.40 dm³ B. 11.20 dm³ C. 2.24 dm³ D. 1.12 dm³ Show Content Detailed Solution 2NaHCO_3(s) → Na₂CO_3(s) + H₂O_(l) + CO₂ Relative molecular mass of NaHCO₃ = 23 +1 + 12 + 16 * 3 = 84smol^-1 2 * 84g of NaHCO₃ will be liberated 22.4dm³ or CO₂ at s.t.p 16.8g of NaHCO₃ will libertae (16.8 * 22.4)/(2 * 84) = 2.24 dm³	C
5.	300 cm³ of gas has a pressure of 800 mmHg. If the pressure is reduced to 650 mmHg, find its volume A. 243.75 cm³ B. 369.23 cm³ C. 738.46 cm³ D. 1733.36 cm³ Show Content Detailed Solution P₁V₁= P₂V₂ 800 * 300 = 650 * V₂ V₂ = (800 * 300)/650 = 369.23 cm³	B
6.	Diffusion is slowest in solid particles than in particles of liquid and gases because A. solid particles have more kinetic energy than the particles of liquid and gases B. solid particles have less kinetic energy than the particles of liqiud and gases C. solid particles have less restriction in their movement than liquid and gas particles D. the particles in solids are far apart and the cohesive forces between them are negligible	B
7.	The experiment that showed that atoms have tiny positively charged nucleus was first carried out by A. Moseley B. Rutherford C. Millikan D. Dalton	B
8.	The atom of an element X is represented as _z^yX. The basic chemical properties of X depends on the value of A. Y B. Z C. Y - Z D. Z - Y	B
9.	The diagram above represent the electron sub-level for A. carbon B. nitrogen C. oxygen D. flourine	C
10.	In the periodic table, the electrical and thermal conductivities are properties of elements that A. decrease across the period and increase down the group B. increase across the period and decrease down the group C. decrease across the period and down the group` D. increase acrosss the period and down the group	A

1.	Chlorophyll obtained from given leaves of plant can be shown to be composed of more than one coloured component by the technique of A. crystallization B. hydrolysis C. chromatography D. sublimation	C
2.	In countries where the temperature falls below 273K, salt is always sprinkled on the icy road in order to A. lower the melting point of the ice B. increase the density of the ice C. make the ice impure D. raise the melting point of the ice	A
3.	2Na_(s) + 2H₂O_(l) → 2NaOH_(aq) + H_2(g) From the equation above, calculate the mass of sodium hydroxide produced by 2.3g of sodium. [H = 1, O = 16, Na = 23] A. 0.40g B. 0.80g C. 4.00g D. 8.00g Show Content Detailed Solution 2Na_(s) + 2H₂O_(l) → 2NaOH_(aq) + H_2(g) Relative molecular mass of NaOH = 23 + 16 + 1 = 40smol^-1 2 * 23g of sodium react with water to produce 2 * 40g of NaOH ∴ 2.3g of sodium will react with water to produce (2.3 * 40 * 2)/(23 * 2) = 4.00g	C
4.	16.8 g of sodium hydrogen trioxocarbonate (IV) is completely decomposed by heat. Calculate the volume of carbon(IV) oxide given off s.t.p [Na 23, C = 12, O = 16, H = 1, Molar volume of a gas at s.t.p = 22.4 dm³] A. 22.40 dm³ B. 11.20 dm³ C. 2.24 dm³ D. 1.12 dm³ Show Content Detailed Solution 2NaHCO_3(s) → Na₂CO_3(s) + H₂O_(l) + CO₂ Relative molecular mass of NaHCO₃ = 23 +1 + 12 + 16 * 3 = 84smol^-1 2 * 84g of NaHCO₃ will be liberated 22.4dm³ or CO₂ at s.t.p 16.8g of NaHCO₃ will libertae (16.8 * 22.4)/(2 * 84) = 2.24 dm³	C
5.	300 cm³ of gas has a pressure of 800 mmHg. If the pressure is reduced to 650 mmHg, find its volume A. 243.75 cm³ B. 369.23 cm³ C. 738.46 cm³ D. 1733.36 cm³ Show Content Detailed Solution P₁V₁= P₂V₂ 800 * 300 = 650 * V₂ V₂ = (800 * 300)/650 = 369.23 cm³	B

6.	Diffusion is slowest in solid particles than in particles of liquid and gases because A. solid particles have more kinetic energy than the particles of liquid and gases B. solid particles have less kinetic energy than the particles of liqiud and gases C. solid particles have less restriction in their movement than liquid and gas particles D. the particles in solids are far apart and the cohesive forces between them are negligible	B
7.	The experiment that showed that atoms have tiny positively charged nucleus was first carried out by A. Moseley B. Rutherford C. Millikan D. Dalton	B
8.	The atom of an element X is represented as _z^yX. The basic chemical properties of X depends on the value of A. Y B. Z C. Y - Z D. Z - Y	B
9.	The diagram above represent the electron sub-level for A. carbon B. nitrogen C. oxygen D. flourine	C
10.	In the periodic table, the electrical and thermal conductivities are properties of elements that A. decrease across the period and increase down the group B. increase across the period and decrease down the group C. decrease across the period and down the group` D. increase acrosss the period and down the group	A