Practice Respiration Lab Problems  The answers are at the bottom, separated by large gaps so you have to scroll down to see them...


Calculate the heat produced (absorbed by the water) using the following formula:

heat (calories) = mass of water (g) x temperature chang   (^oC) x 1 cal / (g) (^oC)

Convert calories to kilocalories by dividing the amount you calculated above by 1,000.

Calculate the mass of the nut that burned. To do this, subtract the mass that remained from the initial mass of the nut. (The stand/pin/stopper/Al-boat doesn’t change so it just subtracts out.)

Find the caloric value of the nut by dividing the kilocalories of heat produced by the mass of the nut of that burned:

caloric value = Kcal / g of nut burned   

a) mass of aluminum can - empty

b) mass of aluminum can + water

c) mass of water (b-a) in grams

d) mass of the nut on the stand (with the Al foil platform & the rubber stopper)

e) mass of the ashes on the stand

f) mass of the nut that actually burnt up (d-e) in grams

g) initial temperature of the water

h) final temperature of the water

i) change in water temperature (h-g) in oC

j) Heat absorbed by the water (c x i x 1 cal / (g) (oC)) in calories

k) Heat absorbed by the water in kilocalories (j/1000)

l) Caloric value (k/f) in kcal/gm

1)  A group of students measured their walnut, stand and aluminum foil boat at 21.41 grams. They measured the aluminum can as 19.0 grams, and after adding water remeasured it as 69.0 grams.  The initial water temperature was 22.0 ^oC.. After burning the nut the water temperature was 80.0 ^oC, and the Al boat, stand and walnut ash had a mass of 18.41 gms.

2)   group of students measured their walnut, stand and aluminum foil boat at 22.41 grams. They measured the aluminum can as 19.0 grams, and after adding water remeasured it as 69.0 grams.  The initial water temperature was 22.0 ^oC.. After burning the nut the water temperature was 80.0 ^oC, and the Al boat, stand and walnut ash had a mass of 18.41 gms.

3)  A group of students measured their walnut, stand and aluminum foil boat at 21.41 grams. They measured the aluminum can as 19.0 grams, and after adding water remeasured it as 69.0 grams.  The initial water temperature was 20.0 ^oC.. After burning the nut the water temperature was 80.0 ^oC, and the Al boat, stand and walnut ash had a mass of 18.41 gms.

4)  A group of students measured their walnut, stand and aluminum foil boat at 22.41 grams. They measured the aluminum can as 17.0 grams, and after adding water remeasured it as 69.0 grams.  The initial water temperature was 22.0 ^oC.. After burning the nut the water temperature was 80.0 ^oC, and the Al boat, stand and walnut ash had a mass of 18.41 gms.

[5] A group of students measured their walnut, stand and aluminum foil boat at 20.38 grams. They measured the aluminum can as 19.2 grams, and after adding water remeasured it as 68.29 grams.  The initial water temperature was 22.5 ^oC.. After burning the nut the water temperature was 80.9 ^oC, and the Al boat, stand and walnut ash had a mass of 16.0 gms.

[6] Another group of students measured a marshmallow in the stand as 21.35 grams. Their can massed 18.6 grams  and with water 76.87 grams. The initial temperature of the water was 22.6 ^oC. After heating the water was 27.3 ^oC. The stand/Al boat and ash had a mass of 19.3 gms.

[7] A group measured the Al can as 18.2 gms and added 21.6 ^oC. water so that the mass was 137.1 grams. Their nut on its stand measured 21.49 grams before the experiment and 20.1 grams after the experiment. The water had a peak temperature of 59.9 ^oC.

[8] A group of students measured their walnut, stand and aluminum foil boat at 21.38 grams. They measured the aluminum can as 19.2 grams, and after adding water remeasured it as 68.29 grams.  The initial water temperature was 22.5 ^oC.. After burning the nut the water temperature was 80.9 ^oC, and the Al boat, stand and walnut ash had a mass of 20.0 gms.

[9] Another group of students measured a marshmallow in the stand as 20.35 grams. Their can massed 19.6 grams  and with water 76.87 grams. The initial temperature of the water was 22.6 ^oC. After heating the water was 27.3 ^oC. The stand/Al boat and ash had a mass of 20.3 gms.

[10] A  group measured the Al can as 20.2 gms and added 21.6 ^oC. water so that the mass was 127.1 grams. Their nut on its stand measured 21.49 grams before the experiment and 20.1 grams after the experiment. The water had a peak temperature of 59.9 ^oC.



Answers below.....

	1.00
a) mass of aluminum can - empty	19.00
b) mass of aluminum can + water	69.00
c) mass of water (b-a) in grams	50.00
d) mass of the nut on the stand (with the Al foil platform & the rubber stopper)	21.41
e) mass of the ashes on the stand	18.41
f) mass of the nut that actually burnt up (d-e) in grams	3.00
g) initial temperature of the water	22.00
h) final temperature of the water	80.00
i) change in water temperature (h-g) in oC	58.00
j) Heat absorbed by the water (c x i x 1 cal / (g) (oC)) in calories	2900.00
k) Heat absorbed by the water in kilocalories (j/1000)	2.90
l) Caloric value (k/f) in kcal/gm	0.97

	2.00
a) mass of aluminum can - empty	19.00
b) mass of aluminum can + water	69.00
c) mass of water (b-a) in grams	50.00
d) mass of the nut on the stand (with the Al foil platform & the rubber stopper)	22.41
e) mass of the ashes on the stand	18.41
f) mass of the nut that actually burnt up (d-e) in grams	4.00
g) initial temperature of the water	22.00
h) final temperature of the water	80.00
i) change in water temperature (h-g) in oC	58.00
j) Heat absorbed by the water (c x i x 1 cal / (g) (oC)) in calories	2900.00
k) Heat absorbed by the water in kilocalories (j/1000)	2.90
l) Caloric value (k/f) in kcal/gm	0.73
	3.00
a) mass of aluminum can - empty	19.00
b) mass of aluminum can + water	69.00
c) mass of water (b-a) in grams	50.00
d) mass of the nut on the stand (with the Al foil platform & the rubber stopper)	21.41
e) mass of the ashes on the stand	18.41
f) mass of the nut that actually burnt up (d-e) in grams	3.00
g) initial temperature of the water	20.00
h) final temperature of the water	80.00
i) change in water temperature (h-g) in oC	60.00
j) Heat absorbed by the water (c x i x 1 cal / (g) (oC)) in calories	3000.00
k) Heat absorbed by the water in kilocalories (j/1000)	3.00
l) Caloric value (k/f) in kcal/gm	1.00
	4.00
a) mass of aluminum can - empty	17.00
b) mass of aluminum can + water	69.00
c) mass of water (b-a) in grams	52.00
d) mass of the nut on the stand (with the Al foil platform & the rubber stopper)	22.41
e) mass of the ashes on the stand	18.41
f) mass of the nut that actually burnt up (d-e) in grams	4.00
g) initial temperature of the water	22.00
h) final temperature of the water	80.00
i) change in water temperature (h-g) in oC	58.00
j) Heat absorbed by the water (c x i x 1 cal / (g) (oC)) in calories	3016.00
k) Heat absorbed by the water in kilocalories (j/1000)	3.02
l) Caloric value (k/f) in kcal/gm	0.75
	5.00
a) mass of aluminum can - empty	19.20
b) mass of aluminum can + water	68.29
c) mass of water (b-a) in grams	49.09
d) mass of the nut on the stand (with the Al foil platform & the rubber stopper)	20.38
e) mass of the ashes on the stand	16.00
f) mass of the nut that actually burnt up (d-e) in grams	4.38
g) initial temperature of the water	22.50
h) final temperature of the water	80.90
i) change in water temperature (h-g) in oC	58.40
j) Heat absorbed by the water (c x i x 1 cal / (g) (oC)) in calories	2866.86
k) Heat absorbed by the water in kilocalories (j/1000)	2.87
l) Caloric value (k/f) in kcal/gm	0.65
	6.00
a) mass of aluminum can - empty	18.60
b) mass of aluminum can + water	76.87
c) mass of water (b-a) in grams	58.27
d) mass of the nut on the stand (with the Al foil platform & the rubber stopper)	21.35
e) mass of the ashes on the stand	19.30
f) mass of the nut that actually burnt up (d-e) in grams	2.05
g) initial temperature of the water	22.60
h) final temperature of the water	27.30
i) change in water temperature (h-g) in oC	4.70
j) Heat absorbed by the water (c x i x 1 cal / (g) (oC)) in calories	273.87
k) Heat absorbed by the water in kilocalories (j/1000)	0.27
l) Caloric value (k/f) in kcal/gm	0.13
	7.00
a) mass of aluminum can - empty	18.20
b) mass of aluminum can + water	137.10
c) mass of water (b-a) in grams	118.90
d) mass of the nut on the stand (with the Al foil platform & the rubber stopper)	21.49
e) mass of the ashes on the stand	20.10
f) mass of the nut that actually burnt up (d-e) in grams	1.39
g) initial temperature of the water	21.60
h) final temperature of the water	59.90
i) change in water temperature (h-g) in oC	38.30
j) Heat absorbed by the water (c x i x 1 cal / (g) (oC)) in calories	4553.87
k) Heat absorbed by the water in kilocalories (j/1000)	4.55
l) Caloric value (k/f) in kcal/gm	3.28
	8.00
a) mass of aluminum can - empty	19.20
b) mass of aluminum can + water	68.29
c) mass of water (b-a) in grams	49.09
d) mass of the nut on the stand (with the Al foil platform & the rubber stopper)	21.38
e) mass of the ashes on the stand	20.00
f) mass of the nut that actually burnt up (d-e) in grams	1.38
g) initial temperature of the water	22.50
h) final temperature of the water	80.90
i) change in water temperature (h-g) in oC	58.40
j) Heat absorbed by the water (c x i x 1 cal / (g) (oC)) in calories	2866.86
k) Heat absorbed by the water in kilocalories (j/1000)	2.87
l) Caloric value (k/f) in kcal/gm	2.08
	9.00
a) mass of aluminum can - empty	19.60
b) mass of aluminum can + water	76.87
c) mass of water (b-a) in grams	57.27
d) mass of the nut on the stand (with the Al foil platform & the rubber stopper)	20.35
e) mass of the ashes on the stand	20.30
f) mass of the nut that actually burnt up (d-e) in grams	0.05
g) initial temperature of the water	22.60
h) final temperature of the water	27.30
i) change in water temperature (h-g) in oC	4.70
j) Heat absorbed by the water (c x i x 1 cal / (g) (oC)) in calories	269.17
k) Heat absorbed by the water in kilocalories (j/1000)	0.27
l) Caloric value (k/f) in kcal/gm	5.38
	10.00
a) mass of aluminum can - empty	20.20
b) mass of aluminum can + water	127.10
c) mass of water (b-a) in grams	106.90
d) mass of the nut on the stand (with the Al foil platform & the rubber stopper)	21.49
e) mass of the ashes on the stand	20.10
f) mass of the nut that actually burnt up (d-e) in grams	1.39
g) initial temperature of the water	21.60
h) final temperature of the water	59.90
i) change in water temperature (h-g) in oC	38.30
j) Heat absorbed by the water (c x i x 1 cal / (g) (oC)) in calories	4094.27
k) Heat absorbed by the water in kilocalories (j/1000)	4.09
l) Caloric value (k/f) in kcal/gm	2.95