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# Calories...Help!

A researcher studying the nutritional value of a new candy places a 3.40 gram sample of the candy inside a bomb calorimeter and combusts it in excess oxygen. The observed temperature increase is 2.36 C. If the heat capacity of the calorimeter is 46.80 kJ*K-1, how many nutritional calories are there per gram of the candy?

### 1 Answer by Expert Tutors

Reno O. B. | Chemistry and Mathematics TutorChemistry and Mathematics Tutor
4.8 4.8 (79 lesson ratings) (79)
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Heat released=heat capacity*change in temperature
#calories=#joules*(1 calorie/4.184 J)

a) convert heat capacity to joules per Kelvin (multiply Heat capacity by 1000 J/kJ)
b) determine heat released by multiplying heat capacity by change in temperature (2.36 C is equivalent to 2.36 K)
c) determine calories by multiplying value of joules by (1 cal/4.184 J)
d) determine calories per gram by dividing value of calories by mass of candy (3.40 grams)

1) heat released (in calories)=
46.80 kJ/K * 1000 J/kJ  or 46, 800 J/K
46,800 J/K * 2.36 K or 110, 448 J
110, 448 J * (1 cal/4.184 J) or 26, 398 cal

2) # calories per gram=26, 398 calories/3.40 grams or 7, 764 calories/gram