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A serving holds 5 g protein, 31 g carbohydrate and 12 g fat. Using 4, 4 and 9 Calories per gram, what is its energy content?
A192 Calories
B252 Calories
C432 Calories
D144 Calories
Answer & Solution
Correct answer: B. 252 Calories
1. Protein gives 5 g times 4 Calories per gram, which is 20 Calories.
2. Carbohydrate gives 31 g times 4 Calories per gram, which is 124 Calories.
3. Fat gives 12 g times 9 Calories per gram, which is 108 Calories.
4. Adding the three gives 20 plus 124 plus 108, which is 252 Calories.
5. Using 4 Calories per gram for fat as well would give 192 Calories, understating the total.
_Source: OpenStax Chemistry (CC BY 4.0), Ch 5 "Thermochemistry", section 5.2 Calorimetry_
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