EXPLAINING A HEATING CURVE FOR ICE, WATER & STEAM

FIRSTLY WE NEED TO REMEMBER THE 3 STATES OF MATTER INVOLVED: ICE STEAM WATER

AND THE CHANGES OF STATE THAT OCCUR DURING HEATING: ICE MELTING EVAPORATION WATER STEAM

We follow the temperature as we heat up the ice using the apparatus shown below Thermometer HEAT

We record the temperature in the beaker as the ice is heated on a graph Temperature (ºC) Time (Seconds)

As we heat the solid the temperature rises steadily It then levels off as the solid melts Temperature (ºC) Time (Seconds)

As the temperature goes up again, we’re heating the gas The liquid is then heated steadily Temperature (ºC) Until it levels off as the liquid boils Time (Seconds) As the temperature goes up again, we’re heating the gas

These graphs can then be used to find the melting and boiling points of the chemical being heated up Time (Seconds) Gas Boiling Point Liquid Melting Point Solid

WHY DO WE GET THE LEVELLING OFF AREAS? Time (Seconds) Gas Liquid Solid As the change of state happens energy is absorbed to break bonds between the particles in the solid & so the temperature doesn’t rise until they all broken!!

FREEZING POINT = MELTING POINT Of course we can do COOLING CURVES as well, to look something like this Gas Boiling Point Liquid Freezing Point Solid REMEMBER FREEZING POINT = MELTING POINT OF LIQUID OF SOLID

WE ARE DOING THESE CHANGES OF STATE ICE FREEZING CONDENSATION WATER STEAM