I have just completed a lab at school about endothermic and exothermic reactions. I am wondering how it works.
We placed steel wool in oxygen and periodically recorded the temperatures. During the procedure the temperature in the sealed container increased causing the reaction to be endothermic. Is it the steel wool that absorbed heat from the oxygen but the thermometer measure the entire container the heat had to have been absorbed from somewhere.
We also did ammonium chloride and water and Sodium Hydroxide and water.
Please explain how this works and thank you in advance.