When 1.13 g of a granola bar was combusted in a bomb calorimeter, the temperature of \({\text{500 c}}{{\text{m}}^{\text{3}}}\) of water increased from 18.5 °C to 28.0 °C. Calculate the energy value, in kJ per 100 g, of the granola bar to the correct number of significant figures.

energy (released by granola) \( = (500 \times 4.18 \times 9.5 = ){\text{ }}19855{\text{ (J)}}/2.0 \times {10^4}{\text{ (J)}}\);

energy released (in kJ per 100 g) \(\left( {\frac{{19855}}{{1000}} \times \frac{{100}}{{1.13}} = } \right){\text{ }}1757.079\);

\( = 1.8 \times {10^3}{\text{ (kJ per 100 g)}}\);

Allow 1800 (kJ per 100 g).

Award [3] for correct final answer.

Award [2 max] for 1760 (kJ per 100 g).

Remember to allow ECF.

Candidates generally used the appropriate equations to solve for the energy value for part (a) however, many included 1.13g with the mass of water and on quite a few occasions, \({\text{22.4 d}}{{\text{m}}^{\text{3}}}\) was used in the question for to calculate energy per gram. Several missed the final mark for not expressing the final value in 2 significant figures. Candidates were not able to apply the rules for addition and subtraction within the mathematical process. Surprisingly defining dietary fibre in part (b) scored poorly. Many omitted reference to plant material or cellulose; there appears to be a general misunderstanding that any food that is not digested is dietary fibre. Most candidates were able to name two health problems for (b)(ii).