Energy of Nuts - a Calorimetry Experiment

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Procedure 1: Energy of a cashew.
Recorded Data:
 | Trial 1| Trial 2| Trial 3| Trial 4| Trial 5|
Mass of cashew (in grams)| 1.00 g (± 0.01 g)| 1.00 g (± 0.01 g)| 1.70 g (± 0.01 g)| 1.40 g (± 0.01 g)| 1.50 g (± 0.01 g)| Mass of remaining material (in grams)| 0.60 g (± 0.01 g)| 0.30 g (± 0.01 g)| 0.30 g (± 0.01 g)| 0.50 g (± 0.01 g)| 0.80 g (± 0.01 g)| Mass of cashew that burned (in grams)| 0.40 g (± 0.01 g)| 0.70 g (± 0.01 g)| 1.40 g (± 0.01 g)| 0.90 g (± 0.01 g)| 0.70 g (± 0.01 g)| Volume of liquid water (in mL)| 59 mL | 54 mL| 104 mL| 31 mL| 15 mL| Mass of liquid water (in grams)| 59 g| 54 g| 104 g| 31 g| 15 g|

Calculations:
The mass of a particular amount of a substance is equal to the product of the volume of that amount and the density of the substance. Mass = Volume x Density
The density of water is 1.0 g/cm3, so it is assumed that the volume of water in mL will be equal to the mass of the water in g. 1 mL H2O = 1 g H2O
For example, in trial 1,
Volume of liquid water = 59 mL
* Mass of liquid water = 59 g

Observations:
1. While the cashew was burning, the flame barely rose above the nut. 2. The cashew burned for a long duration of time (about 2 minutes). 3. The cashew was completely black (charred) and brittle after it was entirely burnt.

Processed Data:
| Trial 1| Trial 2| Trial 3| Trial 4| Trial 5|
Heat produced by the burning cashew (in cal)| 4720 cal| 4320 cal| 8320 cal| 2480 cal| 1200 cal| Heat produced by 1 gram of cashew (in cal)| 11800 cal| 6171.43 cal| 5942.86 cal| 2755.56 cal| 1714.29 cal | Kilocalories of heat from 1 gram of cashew| 11.80 kcal| 6.17 kcal| 5.94 kcal| 2.76 kcal| 1.71 kcal| Note: All decimal values are approximated to two decimal values. Calculations:

The heat produced by the burning cashew was calculated by the equation: qcashew = mwater x 80 cal/g
where: qcashew = heat produced by the cashew in calories
mwater = mass of the water in grams
80 cal/g = the heat of fusion of ice (the heat needed to melt one gram of ice) For example, in trial 1,
mwater = 59 g
* qcashew = 59 g x 80 cal/g
* qcashew = 4720 cal

Correlation = 0.202914
The heat, in calories, generated by one gram sample of the cashew is calculated by the equation: q= qcashewmcashew
where: q = heat generated per gram of sample in calories
qcashew = heat produced by the burning cashew in calories
mcashew = mass of the cashew that burned in grams
For example, in trial 1,
qcashew = 4720 cal
mcashew = 0.40 g
* q= 4720 cal0.40 g
* q = 11800 cal
The nutritional calories or kilocalories was calculated by dividing the heat generated by 1 gram of sample by 1000. kilocalories (kcal)= q1000 cal/kcal
where: q = heat generated per gram of sample in calories
For example, in trial 1,
q = 11800 cal
* kilocalories= 11800 cal1000
* kilocalories=11.80 kcal

Procedure 2: Energy of a walnut.
Recorded Data:
 | Trial 1| Trial 2| Trial 3| Trial 4| Trial 5|
Mass of walnut (in grams)| 2.29 g (± 0.01 g)| 2.20 g (± 0.01 g)| 2.70 g (± 0.01 g)| 2.00 g (± 0.01 g)| 3.00 g (± 0.01 g)| Mass of remaining material (in grams)| 0.29 g (± 0.01 g)| 0.49 g (± 0.01 g)| 1.20 g (± 0.01 g)| 0.30 g (± 0.01 g)| 0.80 g (± 0.01 g)| Mass of walnut that burned (in grams)| 2.00 g (± 0.01 g)| 1.71 g (± 0.01 g)| 1.50 g (± 0.01 g)| 1.70 g (± 0.01 g)| 2.20 g (± 0.01 g)| Volume of liquid water (in mL)| 54 mL| 50 mL| 36 mL| 12 mL| 69 mL| Mass of liquid water (in grams)| 54 g| 50 g| 36 g| 12 g| 69 g|

Calculations:
The mass of a particular amount of a substance is equal to the product of the volume of that...
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