mcdeltaT notes.notebook
February 05, 2014
Calculating Heat Energy
Q = m c Δ T
*
*
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mcdeltaT notes.notebook
February 05, 2014
Specific heat (capacity) = c =
amount of energy needed
to raise 1 gram of a
o
substance by 1 C
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mcdeltaT notes.notebook
February 05, 2014
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mcdeltaT notes.notebook
February 05, 2014
How much energy is required to heat 355 g of water from 20.0oC to 100.0oC?
Q = (355g)(4.18J/goC)(80.0oC)
Q = 118712 J ~ 119,000 J
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mcdeltaT notes.notebook
February 05, 2014
A 1.6 g sample of a grey metal requires 5.8 J of energy to change its temperature from 23oC to 41oC. Is the metal pure lead?
5.8 J = (1.6 g)(c)(18oC)
5.8 J = c
(1.6)(18oC)
Source: www.periodictable.com
0.20 J/goC = c
Check the specific heat chart...pure lead has a specific head capacity of 0.13 J/goC. Therefore not pure lead.
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mcdeltaT notes.notebook
February 05, 2014
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