particle model of matter exam questions

Question 1

the specific heat capacity of ice is less than the specific heat capacity for water, explain how in question 1 the figure shows this (2)

Answer 1

-the gradient for ice is steeper than that of water’s
-this means that there is less energy required to increase the temperature by a fixed amount

Question 2

a student did an investigation and recorded the temperature until the water produced boiled, but more energy was transferred to the surroundings. describe 2 ways the results of the experiment would have been different (2)

Answer 2

-the ice and water would take longer to increase in temperature
-the ice and water would take longer to change state

Question 3

a student investigated the density of some fruits. the volume was measured of each fruit once. the volume measurements cannot be used to show the method to measure volume gives precise readings. give the reason why. (1)

Answer 3

repeat readings of volume need taking of each fruit to show that the readings are close together

Question 4

when the volume of gas in a syringe is increased, the pressure on the inside walls of the syringe decreased. explain why (3)

Answer 4

• there is more time between collisions of particles and the walls of the syringe
• causes a smaller force on the walls of the syringe
• pressure is the total force per unit of area

Question 5

the temperature of helium in a balloon was increased. the mass and volume of the helium stays constant. explain why the pressure exerted by the helium inside the balloon would increase (4)

Answer 5

• the particles would have more kinetic energy
• so there are more collisions with the walls per second
• greater force exerted in collisions
• greater force exerted on the same area

Question 6

the mass of a metal cube was measured using a top pan balance. the balance had a zero error. explain how the zero error may be corrected after readings has been taken from the balance (2)

Answer 6

• record the value of the zero error when there is no object on the balance
• subtract / add the value of the zero error

Question 7

a bunsen burner is heating some water in a beaker. explain how the internal energy of the water changes as it is heated from 20 degrees to 25 degrees (2)

Answer 7

• the kinetic energy of the particles increases
• which increases the internal energy of the water

Question 8

give 2 reasons why taking repeat readings could provide more accurate data (2)

Answer 8

• reduces the effect of random errors
• helps identify and eliminate any anomalies

Question 9

explain what type of error would be caused if the student’s eye was not in line with the level of the liquid in the tube (2)

Answer 9

• random error
• the level of eye position would not be the same each time

Question 10

the power output of a turbine is directly proportional to the kinetic energy of the air passing the blades each second. describe the effect on the power output when the wind speed is halved.

Answer 10

• mass of air passing through the blades is halved
• decreases the kinetic energy by a factor of 2
• so kinetic energy decreases by a factor of 4
• so power output decreases by a factor of 8