Chemistry, 1994, JAMB Exam, Exam, Paper 1 | Objectives

Paper Info

Year :

1994

Title :

Chemistry

Exam :

JAMB Exam

Paper 1 | Objectives

1 - 10 of 52 Questions

#	Question	Ans
1.	A mixture of sand, ammonium chloride and sodium chloride is best separated by? A. sublimation followed by addition of water and filteration B. sublimation followed by addition of water and evaporation C. addition of water followed by filtration and sublimation D. addition of water followed by crystallization and sublimation	A
2.	A pure solid usually melts? A. over a wide range of temperature B. over a narrow range of temperature C. at a lower temperature than the impure one D. at the same temperature as the impure one	B
3.	At the same temperature and pressure, 50 cm³ of nitrogen gas contains the same number of molecules as? A. 25 cm³ of methane B. 40 cm³ of hydrogen C. 50 cm³ of ammonia D. 100 cm³ of chlorine	C
4.	8g CH₄ occupies 11.2 dm³ at s.t.p. What volume would 22 g of CH₃CH₃ occupy under the same condition? (C = 12, H = 1) A. 3.7 dm³ B. 11.2 dm³ C. 22.4 dm³ D. 33.6 dm³	B
5.	To what temperature must a gas 273 K be heated in order to double both its volume and pressure? A. 298 K B. 546 K C. 819 K D. 1092 K	D
6.	For a gas, the relative molecular mass is equal to 2Y. What is Y? A. The mas of the gas B. The vapour density of the gas C. The volume of the gas D. The temperature of the gas	B
7.	The densities of two gases, X and Y, are 0.5 g dm^-3 and 2.0 dm^-3 respectively. What is the rate of diffusion of X relative to Y? A. 0.1 B. 0.5 C. 2.0 D. 4.0	C
8.	The shape of ammonia molecule is? A. trigonal planar B. octahedral C. square planar D. tetrahedral	A
9.	An increase in temperature causes an increase in the pressure of a gas because? A. it decreases the number of collision between the molecules B. the molecules of the gas bombard the walls of the container more frequently C. it increases the number of collision between the molecules D. it causes the molecules to combine Show Content Detailed Solution The temperature of the gas is proportional to the average kinetic energy of its molecules. Faster moving particles will collide with the container walls more frequently and with greater force. This causes the force on the walls of the container to increase and so the pressure increases.	B
10.	The number of electrons in the valence shell of an element of atomic number 14 is? A. 1 B. 2 C. 3 D. 4	D

1.	A mixture of sand, ammonium chloride and sodium chloride is best separated by? A. sublimation followed by addition of water and filteration B. sublimation followed by addition of water and evaporation C. addition of water followed by filtration and sublimation D. addition of water followed by crystallization and sublimation	A
2.	A pure solid usually melts? A. over a wide range of temperature B. over a narrow range of temperature C. at a lower temperature than the impure one D. at the same temperature as the impure one	B
3.	At the same temperature and pressure, 50 cm³ of nitrogen gas contains the same number of molecules as? A. 25 cm³ of methane B. 40 cm³ of hydrogen C. 50 cm³ of ammonia D. 100 cm³ of chlorine	C
4.	8g CH₄ occupies 11.2 dm³ at s.t.p. What volume would 22 g of CH₃CH₃ occupy under the same condition? (C = 12, H = 1) A. 3.7 dm³ B. 11.2 dm³ C. 22.4 dm³ D. 33.6 dm³	B
5.	To what temperature must a gas 273 K be heated in order to double both its volume and pressure? A. 298 K B. 546 K C. 819 K D. 1092 K	D

6.	For a gas, the relative molecular mass is equal to 2Y. What is Y? A. The mas of the gas B. The vapour density of the gas C. The volume of the gas D. The temperature of the gas	B
7.	The densities of two gases, X and Y, are 0.5 g dm^-3 and 2.0 dm^-3 respectively. What is the rate of diffusion of X relative to Y? A. 0.1 B. 0.5 C. 2.0 D. 4.0	C
8.	The shape of ammonia molecule is? A. trigonal planar B. octahedral C. square planar D. tetrahedral	A
9.	An increase in temperature causes an increase in the pressure of a gas because? A. it decreases the number of collision between the molecules B. the molecules of the gas bombard the walls of the container more frequently C. it increases the number of collision between the molecules D. it causes the molecules to combine Show Content Detailed Solution The temperature of the gas is proportional to the average kinetic energy of its molecules. Faster moving particles will collide with the container walls more frequently and with greater force. This causes the force on the walls of the container to increase and so the pressure increases.	B
10.	The number of electrons in the valence shell of an element of atomic number 14 is? A. 1 B. 2 C. 3 D. 4	D