Unit 5 Solid, Liquids and Gases Flashcards
What is the formula for density?
mass (kg) / volume (m³) = density (kg/m³)
What is the formula for pressure?
pressure (Pa) = force (N) / distance (m)
What is the formula for pressure difference?
height (m) x density (kg/m³) x gravitational field strength (10N)
What is the definition of density?
the amount of mass per unit of volume
What is the definition of pressure?
how much force exerted upon a certain amount of area
What is the pressure difference?
the difference in pressure between two points, varying between the height, GPE and density.
How does pressure act upon a fluid?
pressure is equal in all directions of a fluid (liquid/gas) because they don’t have a fixed shape and can move freely.
What does heating up a substance do to the particles?
it makes the particles move faster due to the increase in temperature which increases the energy stored (KE). it can also change state.
What is temperature?
the average measure of the amount of KE in a substance/particle
Describe what happens when a substance melts
increases in temperature, the solid particles gain energy and become less ordered, they then move freely
Describe what happens when a substance evaporates
the temperature increases, the pressure decreases, the liquid particles gain energy and escape from the surface and enter the gas phase
What does boiling involve?
rapid vaporisation and bubble formation
Describe the arrangement and motion of particles in solids, liquids and gases
solids: tightly packed only vibrate
liquids: close together and move freely
gases: gar apart and move freely in random motion (exerting force and pressure on container when colliding with walls)
Define specific heat capacity
the amount of energy required to change the temperature of 1kg of an object by 1°C
What is the temperature of absolute 0°C in kelvins?
-273°K
