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# Calorimeter 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?

Harley,

Remember the equation

ΔH = -Ccal x ΔT.

Hints:

1) make sure ΔT in in K
2) 1 nutritional calorie = 4.2 kJ
3) give the answer on a per gram basis of candy

I think you can take it from here!!

Carol,

Unfortunately, I am still not coming up with the correct answer. I don't know if I am calculating wrong or what?

Harley
Do you want to share your work so far?  I may be able to help if I see what you've tried.
I multiplied 46.80 x 2.36 then took that answer and converted calories. And finally divided it by 3.40.
Harley, Here's what I get

ΔH = -Ccal x ΔT
- 46.80 kJ/K x 2.36 K = -110.448 kJ

convert to nutritional calories
-110.48 kJ (1 Calorie/4.2 kJ) = -26.3 Calorie

Calories per gram
-26.3 C/ 3.40 g = -7.73 Calorie/gram

Did you get something different?