5 SOLIDS, LIQUIDS AND GASES Flashcards
Unit for temperature (non-gas law)
Degree Celcius (‘C)
Unit for temperature (gas law)
Kelvin (K)
Unit for energy
Joule (J)
Unit for mass
Kilogram (kg)
Unit for density
Kilogram/metre ^3 (kg/m^3)
Unit for distance
Metre (m)
Unit for area
Metre ^2 (m^2)
Unit for volume
Metre ^3 (m^3)
Unit for speed
Metre/second (m/s)
Unit for acceleration
Metre/second ^2 (m/s^2)
Unit for force
Newton (N)
Unit for pressure
Pascal (Pa)
Unit for Specific Heat Capacity
Joules / Kilogram degree celsius (J/kg’C)
Density equation
Density = Mass / Volume
Density symbol equation
p = m / v
Define density
The ammount of mass per unit volume
How to find density of regular object
- Find mass - use mass blance (tare/zero) [in kg]
- Find volume - V = l x h x w, use ruler [in m]
- Density eqution
How to find density of irregualr object
- Volume displacement - use eureka can
- Lower slowly until fully submerged
- Use measureing cylinder for displaced water
- Find mass - use mass balance (tare/zero) [in kg]
- Use density equation
Pressure equation
Pressure = Force / Area
Pressure symbol equation
p = F / A
Pressure difference equation
Pressure difference = density x depth x gravitational field strength
Pressure difference symbol equation
p = pgh
Pressure difference symbol equation
p = pgh
What can be said about pressure on a particle in a liquid or gas not in flow
Pressure rests and acts equally in all directions of the particle
Arrangement of a solid
- Regualr arrangement
- Tightly packed
- Strong forces between particles
- Vibrate about fixed positions
Arrangement of a liquid
- Irregular arrangement
- Tightly packed - take shape of container
- Quite strong forces between particles
- Can slide/flow over each other
Arrangement of a gas
- Random arrangemt
- Expand to fill space avaliable
- Weak forces between particles
- Free to move
How does heating particles increase the temperature or change their state
- There’s a thermal energy transfer to substances upon heating
- Particles gain KE, move faster, and temperature increases
- Thermal energy transfer from heating to particles is sued to break bonds, and change state
Describe an investigation to find how temperature affects the change of state of Steraic acid
- Fill beaker with water, place on gause on tripod over bunsen on heatproof mat
- Place solid stearic acid in boiling tibe with thermometer and melt
- Remove and start stopwatch, taking regular temperature readings unitl it reaches 50c
- Plot a temperature-time graph
On a temperature-time graph, what does the sharp gradient at the start represent
- Cooling
- Large temperature difference between surroundings and stearic acid
- Steep gradient
On a temperature-time graph what does a flat line represent
- Change of state
- All thermal energy used to break bonds between particles
On a temperature-time graph, what does the shallow line represent
- Small temperature difference between stearic acid and surroundings
- Less steep gradient
Define specific heat capacity
The energy required to change the temperature of an object by one degree celcius, per kilogram of mass
Equation for change in thermal energy
Change in thermal energy = mass x specific heat capacity x change in temperatue
Symbol equation for change in thermal energy
xQ = mcxT
Describe an investigation to find the specific heat capacity of a metal block
- In burr holes of a metal block, place nad immersion heater and thermometer covered in lagging
- Connect immersion heater in circuit with power supply, ammeter (in series) and voltemeter (in parallel)
- Measure initial temperature with thermometer
- Start stopwatch and switch on power, measure current and voltage with ammeter and voltmeter
- After 7mins switch off power and measure final temperature
- IVt = mcxT
How does Brownian Motion show particles
- Tiny invisible air particles (invisible to the naked eye) collide with larger smoke particles
- Transfer some momentum to smoke
- Causes smoke particles to move randomly
How do particles exert pressure on a container
- Fast moving and randomly moving gas particles collide with sides, changing velocity which requires a force from the side on the gas particle
- Ft = xP, as gas particles change momentul, N3L states that gas will exert an equal and oppposite force on the side
- Pressure = Force / Area so gas exerts pressure on the side
How does temperature relate to the speed of molecules
As temperature increases, speed increases and KE is transferred to the molecules from thermal energy
How do fast moving particles increse pressure on a container
Faster moving particles cillide with force on wall, and more frequently, increasing pressure
What is the relationship between temperature in Kelivn of a gas molecule and the KE
Kelvin temp is proportional to the average KE of it’s molecule
What is 0K in ‘C
-273
How to covert K to ‘C
-273
How to convert ‘C to K
+273
Why is 0k known as abosloute zero
Partices have no energy, ans so stop moving
Volume Gas Law
P1V1 = P2V2
Temperature Gas Law
P1/T1 = P2/T2 - KELIVN
Temperature Gas Law
P1/T1 = P2/T2 - KELIVN
What must gas law equations have
Temperature in Kelvin
What must remain fixed for P1V1 = P2V2
Fixed mass, and temperature
What must remain fixed for P1/T1 = P2/P2
Fixed mass, and volume
