P6 Flashcards
What is mass
The amount of matter an object has
What is volume
The amount of space an object takes up
What is the equation fordensity?
Density(kg/m3)=mass(kg)/volume(m3)
What is density
Mass per unit of volume
Required practical A regular shapes
Find the length,height and width
Multiply them together to get the volume
Weigh it
Calculate density
What is the piece of equipment you can use to improve measurements
Vernier
Required practical A irregular shapes
Use scales for mass
Set up eurka can
Carefully lower object into eureka can
Collect overflowing water into measuring cylinder
That is your volume
Use the mass and volume for the density,
How do you ensure your eureka can is accurate
Fill it with more water (covering the spout)and wait for the water to stop coming out of the spout - right level- even
What is another way tofind the density of an irregular shape
Find the mass
Have an initial volume in a measuring cylinder (how much water is in it to begin with)
Place the object into the cylinder and take mother reading for your final volume
Then find the difference in the 2 readings toget your volume
Then find your density using the mass and the difference in the readings (volume)
How to find the density of a liquid
Put a measuring cylinder onto the scales and set it to 0
Put the liquid at 25cm3
Write down the mass of the liquid when it is at 25m3
Now you have the mass and volume(25m3) so you can figure out density
How can you tell if a substance is pure
Their boiling points
Describe a solid
-particles are uniformly arranged in a tightly packed lattice
-vibrate in a fixed position
-low energy high density
-cannot be compressed
-retains fixed shaped
Describe a liquid
-particles are in contact with each other but are not in a fixed position
-particles move and slide past each other
-moderate energy and density
-Cannot be compressed
- filled the shape of the bottom of any container
Describe a gas
-particles are widely spread and rarely In contact
-move rapidly and freely into any available space
-high energy low density
-can be compressed
-fills the entirety of any enclosed container
differences between evaporation and boiling
Evap:
-no bubbles
-takes place only on surface of liquid
-slower
-occurs that any temp
-thermal energy from surroundings
Boiling:
-bubbles throughout liquid
-takes place throughout liquid
-faster
-boils at specific temp
-needs thermal energy from external source
what are the similarities between evaporation and boiling
-both involve liquids turning into gas
-both need energy
-both are physical changes
in the heating curve why is there a straight line
no change in temp because all energy is going to breaking up bonds between particles- this is latent heat
what is latent heat
the amount of energy needed to change the state of 1kg of a material with out changing its temp
why would a straight line in the cooling curve not be straight
impure substance like tap water
what is kinetic energy
energy due to movement
what is gravitational potential energy
energy due to height
what is internal heat
the total energy that particles in a system is equal to the sum of their kinetic and potential energy stores
what is potential energy
the PES of a system is due to breaking of bonds or making of bonds and position of particles
what are factors that effect internal energy
-heating a substance
-doing work on a gas (squeezing it)—>because you are pushing particles closer together
