Solids, liquids and gases

Question 1

unit for energy

Answer 1

joules (j)

Question 2

units for temperature

Answer 2

degrees celsius (cº) and kelvins (k)

Question 3

kelvins to celsius

Answer 3

0 K = -273 celcius

Question 4

unit for pressure

Answer 4

pascal (Pa) or kilopascal (kPa)

Question 5

unit for force

Answer 5

newtons (N)

Question 6

unit for density

Answer 6

grams per cubic centimeter (g/cm3)

Question 7

unit for heat capacity

Answer 7

joules/kilogram degree Celsius (J/kg °C)

Question 8

the relationship between density, mass and volume

Answer 8

density (P) = mass (m) / volume (v)

Question 9

investigate density using direct measurements of mass and volume

Answer 9

*density can be found by measuring the mass and volume and applying the formula
* For a regular object use a ruler to measure the lengths needed to determine the volume.
* For an irregular object submerge it in water and measure the displaced volume.
* Measure the mass of either type of object using a measuring balance.

Question 10

the relationship between pressure, force and area

Answer 10

pressure (Pa) = force (N)/ area (m2)

Question 11

State what direction the pressure at a point in a gas or liquid acts

Answer 11

the pressure at a point in a gas or liquid at rest acts equally in all
directions

Question 12

the formula for pressure difference

Answer 12

Pressure difference [Pa] = Density [kg/m3] x gravitational field strength [N/kg] x Height [m]

P = m x g x h

Question 13

explain how molecules in a gas have random motion and that they exert a force and hence a pressure on the walls of a container

Answer 13

Gas molecules have rapid and random motion due to the random collisions with other gas molecules and the walls of the container
Pressure = Force/Area