Chemistry

08. Determination of an enthalpy change of combustion

  • 00:40 Why is it important to keep the lid on the burner when not being used?
  • 00:44 Why is it important to know the initial temperature of the water?
  • 00:52 Why is it important to remove the lighted splint quickly after igniting the wick?
  • 00:55 Why is it not important to try to achieve a temperature rise of exactly 40oC?
  • 01:02 Why does the cap extinguish the flame?

  • de-ionised water

  • digital balance (pref. 3-decimal place but minimum 2-dp)

  • clamp stand

  • 250 cm3 conical flask

  • spirit burner

  • heat-proof mat

  • thermometer

Hazard Risk Control measure

Ethanol – fflamadwy iawn Methanol – fflamadwy, gwenwynig iawn a pherygl iechyd difrifol.

Os nad yw’r llosgydd yn cael ei ddiffodd yn gywir, mae gwirod sydd wedi gollwng o’r llosgydd o gwmpas y wic yn gallu tanio.

Llygad: golchwch â digonedd o ddŵr tap (10 munud).
Croen / dillad: diffoddwch y fflamau gan ddefnyddio planced dân neu ddefnydd arall addas. Oerwch groen sydd wedi cael llosg o dan y tap (10 munud).