Energy Content of Food - Practical Skills

Question 1

What needs to be measured to determine the energy content of food?

Answer 1

• Change in water temperature
• Mass of food ( should be the same for each sample)

Question 2

State the formula for calculating the energy value of a food sample

Answer 2

Energy = mass of water * temperature change *4.2

Question 3

Why should the boiling tube be at an angle?

Answer 3

So water can be heated more evenly

Question 4

What should be done when the flame of the burning food sample goes out?

Answer 4

Relight it and continue to heat the water until the food sample does not relight anymore

Question 5

State 2 sources of error in this practical

Answer 5

• Incomplete combustion of food sample
• Heat loss to surroundings
• Inconsistent angle of boiling tube

Question 6

State a hazard and safety precaution involved in this practical

Answer 6

Take care to keep hands away from burning food, dripping fat from the food sample and the Bunsen flame