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Data Unknown Identifier(s) (a) Mass of empty styrofoam cups (b) Mass of cups 100

ID: 532611 • Letter: D

Question

Data Unknown Identifier(s) (a) Mass of empty styrofoam cups (b) Mass of cups 100 mL water (c) Mass of cups 100 mL water hot metal (d) Initial temperature of water in the calorimeter (cups) (e) Temperature of the boiling water bath Final temperature of water added hot metal Calculations (g) Mass of water in cups, mcw.[b-a] (h) Mass of added hot metal, mHM Te-b] li) Temperature change of the water in the calorimeter (AT G) Temperature change of the added hot metal (AT, Tf-Ti x AT Calculate the heat gained by the calorimeter B x AT, (m) Calculate the total heat gained AH (n) Since AH calculate the heat lost Earned by the hot metal AHM -AH (o) Calculate the specific heat capacity of the metal from x AT x C (D) Atomic weight nf metal Metal 2 Metal 1. 2.61 g 10 13 g 102.22 150.47 g ZI, Z 2 1,1 13.34 g 21.12 33.09 2. 7 1.2 16 37.29 33, 32 J 91. Z 1661. 3 60 28 72 166 93 J 6023.72

Explanation / Answer

Data Unknown Identifiers

Metal 1

Metal 2

a) Mass of empty Styrofoam cups

8.64 g

9.10 g

b)Mass of cups + 100 mL water

107.48 g

108.22 g

c) Mass of cups +100 mL water + hot metal

150.47 g

141.31 g

d) Initial temperature of water in the calorimeter (cups)

21.4C

21.2C

e) Temperature of the boiling water bath

95.4C

95.6C

f) Final temperature of water + added hot metal

24.2C

25.2C

Calculations

g) Mass of water in cups, mCW, (b – a)

(107.48 – 8.64) g = 98.84 g

(108.22 – 9.10) g = 99.12 g

h)Mass of added hot metal. mHM, (c – b)

(150.47 – 107.48) g = 42.99 g

(141.31 – 108.22) g = 33.09 g

i) Temperature change of the water in the calorimeter (TCW = Tf – Ti(CW))

(24.2 – 21.4)C = 2.8C

(25.2 – 21.2)C = 4.0C

j) Temperature change of the added hot metal (THM = Tf – Ti(HM))

(24.2 – 95.4)C = -71.2C

(25.2 – 95.6)C = -70.4C

k) Calculate the heat gained by the cold water

HCW = mCW*CS*TCW (Cs = 4.18 J/g.C)

(98.84 g)*(4.18 J/g.C)*(2.8C) = 1156.823 J

(99.12 g)*(4.18 J/g.C)*(4.0C) = 1657.864 J

l) Calculate the heat gained by the calorimeter

Hcal = B*TCW (take the value of B from below)

(7.333 J/C)*(2.8C) = 20.5324 J

(7.333 J/C)*(4.0C) = 29.332 J

m) Calculate the total heat gained

Hgained = HCW + Hcal

(1156.823 + 20.5324) J = 1177.3554 J

(1657.864 + 29.332) J = 1687.196 J

n) Since Hgained = -Hlost, calculate the heat lost by the metal

HHM = -Hgained

-(1177.3554 J) = -1177.3554 J

-1687.196 J

o) Calculate the specific heat of the metal

HHM = mHM*CS(HM)*THM

Cs(HM) = HHM/(mHM*THM)

(-1177.3554 J)/(42.99 g).(-71.2C) = 0.3846 J/g.C 0.385 J/g.C

(-1687.196 J)/(33.09 g).(-70.4C) = 0.7242 J/g.C 0.724 J/g.C

Part 1: Determining the calorimetric constant

Data Unknown Identifiers

Trial 1

Trail 2

a) Mass of empty Styrofoam cups

9.64 g

10.41 g

b)Mass of cups + 70 mL water

77.16 g

81.40 g

c) Mass of cups +100 mL water + 30 mL hot water

98.88 g

103.03 g

d) Initial temperature of water in the calorimeter (cups)

21.6C

21.5C

e) Temperature of the boiling water bath

96.6C

93.9C

f) Final temperature of water + added hot water

38.5C

39.1C

Calculations

g) Mass of cool water in cups, mCW, (b – a)

(77.16 – 9.64) g = 67.52 g

(81.40 – 10.41) g = 70.99 g

h)Mass of added hot water, mHW, (c – b)

(98.88 – 77.16) g = 21.72 g

(103.03 – 81.40) g = 21.63 g

i) Temperature change of cool water in the calorimeter (TCW = Tf – Ti(CW)) = (f) – (d)

(38.5 – 21.6)C = 16.9C

(39.1 – 21.5)C = 17.6C

j) Temperature change of added hot water (THW = Tf – Ti(HW)) = (f) – (e)

(38.5 – 96.6)C = -58.1C

(39.1 – 93.9)C = -54.8C

k) Calculate the heat lost by the hot water

HHW = mHW*CS*THW (Cs = 4.18 J/g.C)

(21.72 g)*(4.18 J/g.C)*(-58.1C) = -5274.875 J

(21.63 g)*(4.18 J/g.C)*(-54.8C) = -4954.654 J

l) Calculate the heat gained by the cold water

HCW = mCW*Cs*TCW

(67.52 g)*(4.18 J/g.C)*(16.9C) = 4769.748 J

(70.99 g)*(4.18 J/g.C)*(17.6C) = 5222.592J

m) Calculate the heat gained by the calorimeter

Hcal = -HHW - HCW = -k - l

-(-5274.875 J) – (4769.748 J) = 505.127 J

-(-4954.654 J) – (5222.592 J) = -267.938 J

n) Calculate the calorimetric constant

B = Hcal/TCW = m/i

(505.127/16.9) J/C = 29.889 J/C

(-267.938/17.6) J/C = -15.223 J/C

o) Average calorimeter constant

½*[29.889 + (-15.223)] J/C = 7.333 J/C

Data Unknown Identifiers

Metal 1

Metal 2

a) Mass of empty Styrofoam cups

8.64 g

9.10 g

b)Mass of cups + 100 mL water

107.48 g

108.22 g

c) Mass of cups +100 mL water + hot metal

150.47 g

141.31 g

d) Initial temperature of water in the calorimeter (cups)

21.4C

21.2C

e) Temperature of the boiling water bath

95.4C

95.6C

f) Final temperature of water + added hot metal

24.2C

25.2C

Calculations

g) Mass of water in cups, mCW, (b – a)

(107.48 – 8.64) g = 98.84 g

(108.22 – 9.10) g = 99.12 g

h)Mass of added hot metal. mHM, (c – b)

(150.47 – 107.48) g = 42.99 g

(141.31 – 108.22) g = 33.09 g

i) Temperature change of the water in the calorimeter (TCW = Tf – Ti(CW))

(24.2 – 21.4)C = 2.8C

(25.2 – 21.2)C = 4.0C

j) Temperature change of the added hot metal (THM = Tf – Ti(HM))

(24.2 – 95.4)C = -71.2C

(25.2 – 95.6)C = -70.4C

k) Calculate the heat gained by the cold water

HCW = mCW*CS*TCW (Cs = 4.18 J/g.C)

(98.84 g)*(4.18 J/g.C)*(2.8C) = 1156.823 J

(99.12 g)*(4.18 J/g.C)*(4.0C) = 1657.864 J

l) Calculate the heat gained by the calorimeter

Hcal = B*TCW (take the value of B from below)

(7.333 J/C)*(2.8C) = 20.5324 J

(7.333 J/C)*(4.0C) = 29.332 J

m) Calculate the total heat gained

Hgained = HCW + Hcal

(1156.823 + 20.5324) J = 1177.3554 J

(1657.864 + 29.332) J = 1687.196 J

n) Since Hgained = -Hlost, calculate the heat lost by the metal

HHM = -Hgained

-(1177.3554 J) = -1177.3554 J

-1687.196 J

o) Calculate the specific heat of the metal

HHM = mHM*CS(HM)*THM

Cs(HM) = HHM/(mHM*THM)

(-1177.3554 J)/(42.99 g).(-71.2C) = 0.3846 J/g.C 0.385 J/g.C

(-1687.196 J)/(33.09 g).(-70.4C) = 0.7242 J/g.C 0.724 J/g.C