solids, liquids, and gases Flashcards
density formula
density=mass/volume
density experiment for a regular shaped object
- record mass using scale (check for zero error)
- measure volume using ruler/vernier caliper
- substitute values into the formula ρ=m/v
density experiment for liquid
- place a measuring cylinder onto a scale and tare it
- pour the liquid into the measuring cylinder and record the mass
- read the measurement of volume off the cylinder at: eye level to avoid the parallax error, from the bottom of the meniscus, and on a flat surface
- substitute values into the formula ρ=m/v
density experiment for an irregular object
- record the mass using a balance
- for the volume there are two options:
- eureka can:
- fill the eureka can up to the spout
- submerge the irregular object
- collect the displaced water in a measuring cylinder
- the volume of the displaced water=the volume of the object - fill a cylinder with water
- submerge the irregular object
- the rise in the volume of water=the volume of the irregular object
- substitute values into the formula ρ=m/v
pressure formula for solids
pressure= force/ area
- pascals (Pa)
- 1Pa=1N/m2
pressure in liquids and gases
- acts equally in all directions
- increases with depth
- depends on the density
- doesn’t depend on the shape of the container
pressure and depth
pressure increases with depth
pressure difference formula
Pressure= density x gravitational field strength x height
P= ρ x g x h
properties of solids
- solids have a definite rigid shape and are often very dense (the density of a substance is a measure of how tightly packed the particles are)
- the particles are very closely packed together in a regular arrangement. there are strong forces between the particles which give solid objects their definite shape
- they vibrate about fixed positions, their movement increases with heat because they gain more kinetic energy
properties of liquids
- no definite shape
- particles are still close together and attract one another and hold together but they can slide over each other and move in random directions
- liquids occupy the lowest part of any container and are much more dense than gases but less dense than solids
- irregular arrangement
- their movement increases with heat because they gain more kinetic energy
properties of gases
- particles are very spread out with large spaces between them, forces holding them together are weak
- gases have low densities and no definite shape , they can be compressed
- move randomly at high speeds
- the particles will bump into anything in the gas, or into the walls of the container, and the forces caused by these collisions exert a pressure
why do gases exert pressure inside a container
- the gas particles move at high speeds in random directions inside the container
- as they do this they collide with themselves and the walls of the container, these are called elastic collisions
- this exerts a force on the surface area of the walls and since pressure=force/area this exerts a pressure inside the container
boyle’s law
boyle’s law states that for a fixed amount of gas, at a constant temperature, pressure is inversely proportional to its volume
P1xV1=P2xV2
absolute zero
absolute zero or kelvin zero= -237 degrees celsius
converting kelvin to celsius
temp in k - 237
converting celsius to kelvin
temp in celsius + 237
gay-lussac’s law
gay-lussac’s law states that for a fixed amount of gas, at constant volume, pressure is directly proportional to its temperature IN KELVINS
P1/T1=P2/T2
kinetic energy and temperature
the heat energy is transferred to the kinetic energy of the particles, they have more kinetic energy (they speed up) and the temperature increases
specific heat capacity
the specific heat capacity of a substance is the amount of thermal energy required to raise the temperature of 1kg of that substance by 1 degrees celsius.
specific heat capacity formula
C=ΔQ/mΔT
specific heat capacity= difference in thermal energy/ mass x difference in temperature
J/kg per Celsius
why the specific heat capacity of substances is higher when done in practical than the theoretical value
the SHC of a substance is higher when done in practicals than the theoretical value because we don’t account for the heat dissipated to the surroundings
ΔQ formulas
ΔQ= m x c x ΔT
ΔQ= V x I x t
changes of state
when you heat a substance its kinetic energy increase (because they are directly proportional) but when the substance reaches a certain temperature the kinetic energy will stop increasing and instead the heat will go into the potential energy of the molecules, breaking the bonds between them and changing the state
