Experiment WS 4: 7.3A & B

Kowloon Tong School (Secondary Section)

F.2 Integrated Science

Experiment Worksheets 4

Name: _________________ (    )                                                               Date: __________________

Class: 2 _______

Experiment 7.3A, B: Comparing the energy contents能量值 of different snacks? (P.27 - 30)

Objective: To compare the energy contents of cookies and peanuts.

Design of Experiment: (P.29)

Consider of “3Cs” of a fair test公平測試

n   Variable to be changed: type of snack

n   Variable(s) to be kept constant保持不變: (Put a “Ö” in the appropriate boxes.)

	Weight of food	Ö	Volume of water
	Size of food pieces	Ö	Type of boiling tube
	Type of food	Ö	Type of burning spoon
Ö	Initial temperature of water
Ö	Others: position and distance of burning food from the boiling tube
	of water

n   What to compare: increase in water temperature per gram of snack used

Results: (P.30)

Snack	Weight of snack used (g)	Initial water temperature (oC)	Highest water temperature reached in burning (oC)	Increase in water temperature* (oC)	Increase in temperature per gram of snack used# (oC g-1)
Peanut
Cookies

*Increase in water temperature = Highest water temperature reached – Initial water temperature

#Increase in temperature per gram of snack used =

Discussion: (P.30)

How can you compare the energy contents of the snacks according to you results?

According to the results, the greater (greater / smaller) the increase in water temperature per gram of snack burnt, the higher the energy content of the snack.

Conclusion: (P.30)

The energy contents of peanut is higher / lower (depends on results) than that of cookies.