kinetic model of matter ⛹

Question 1

state the kinetic model of matter

Answer 1

all matter is made out of numerous tiny particles that are always in constant, random motion

Question 2

molecular structure of solids

Answer 2

• molecules are closely packed together in a regular arrangement
• large number of particles per unit volume
• particles vibrate about fixed positions
• particles held in position by very strong forces of attraction between particles

Question 3

molecular structure of liquids

Answer 3

• random arrangement, particles slightly further apart than solid
• slighty smaller number of particles per unit volume
• particles slide over one another
• forces of attraction between particles

Question 4

molecular structure of gases

Answer 4

• random arrangement, particles very far apart from one another
• small number of particles per unit volume
• particles move about randomly at high speeds
• very little attraction between them

Question 5

brownian motion observations

Answer 5

smoke particles move about in a continuous, random manner. the larger the smoke particle, the less agitated the motion

Question 6

brownian motion explanation

Answer 6

air particles are moving continuously, in random directions. the constant, uneven bombardment by the air particles cayses the smoke particles to also move in a continuous, random manner. air particles must be moving at high speeds to cause the much larger smoke particles to change direction

Question 7

effect of temperature on brownian motion

Answer 7

as temperature increases, average speed of air molecules increases. air molecules bombard the smoke particles moe vigorously and frequently. hence, smoke particles move at a higher speed and change direction more frequently due to bombardment by air particles

Question 8

how does a gas exert a pressure on the container walls?

Answer 8

when an air molecules collide with the inner wall, they exert a force over area, giving rise to pressure

Question 9

what happens to pressure when volume increases and temperature stays constant?

Answer 9

when volume increases, the number of air molecules per unit volume decreases. the air molecules collide less frequently with the inner walls ot the container, resulting in a smaller force exerted on the walls. since pressure is total force over unit area, pressure of air decreases

Question 10

what happens to pressure when temperature increases and volume stays constant?

Answer 10

when temperature increases, air molecules have a higher average speed. hence air molcules collide with the walls of the container more frequently and forcefully, resulting in a greater force exerted on the walls. since pressure of total force over unit area, pressure of air increases

Question 11

what happens to volume when temperature increases and pressure stays constant?

Answer 11

when temperature increases, air molecules have a higher average speed, hence air molecules collide with the walls of the container more frequently and forcefully. since volume is not constant, temperature gain will cause the air to expand. air molecules can occupy a greater volume, hence collide with the walls less frequently. the combination of greater average speeds and lower frequency of collisions causes pressure to remain constant