A kilogram of aluminum metal and a kilogram of water are each warmed to 75 ∘C and placed in two identical insulated containers.
One hour later, the two containers are opened and the temperature of each substance is measured. The aluminum has cooled to 35 ∘C while the water has cooled only to 66 ∘C.
The difference is in the amount of heat required to increase their temperature by 1 °C
It takes 4.19 joules to increase the temperature of water by 1 °C compared to Aluminium which is 0.900 joules to raise the temperature by 1 °C. Consequently, Aluminum will cool easily compare to water which will retain some of it heat longer because it does not heat up quickly like Aluminum.
Carbon Dioxide fire extinguishers extinguish fire by taking away the oxygen element of the fire triangle and also be removing the heat with a very cold discharge. Carbon dioxide can be used on Class B & C fires. They are usually ineffective on Class A fires
