Chemistry
Ms. Boon
Name: _________________________________
Period: ______ Date: _______________
Thermochemistry Notes 2
Catalyst: Analyze heat flow in the systems shown on the board here.
Video Demonstration - Focus Question: Are these reactions exothermic or endothermic? How do you know?
States of Matter Vocabulary Review: Use your notes to complete the chart AND bubbles.
PHASE
CHANGE
Solid to Liquid
Liquid to Solid
Liquid to Gas
Gas to Liquid
Solid to Gas
Gas to Solid
CHEMISTRY TERM
ENDOTHERMIC OR
EXOTHERMIC?
The temperature at which a
substance turns from a solid to a
liquid is called the …
The temperature at which a
substance turns from a liquid to a
gas is called the …
Notes: Specific Heat (aka heat capacity or specific heat capacity)
 Specific heat is the amount of __________________ that must be transferred as
______________ to raise the temperature of 1 gram (g) of a substance by 1 Kelvin (K).
 The term used for specific heat is a lowercase “c”. The units for specific heat are Joules/gram*Kelvin or __________.
 Different substances have ______________________ specific heats.
Table 1: Specific Heats at Room Temperature
Substance
Specific Heat
(J/g*K)
Air
1.01
2. What substance has the lowest specific heat?
Aluminum
0.897
Cadmium
0.232
3. Which substance requires more heat energy to increase its
Calcium
0.647
temperature: calcium or gold?
Carbon (graphite) 0.709
Chromium
0.449
4. A substance with a high specific heat requires (more/less) heat
Copper
0.385
energy to raise the temperature of a 1 g sample by 1 K than a
Gold
0.129
substance with a low specific heat.
Granite
0.79
Specific Heat Calculations
Iron
0.449
If we know the specific heat of a substance, we can calculate the amount of
Lead
0.129
heat energy required to raise the temperature of a sample of a substance by a
Neon
1.030
certain amount.
Nickel
0.444
Platinum
0.133
The formula:
Silicon
0.705
Silver
0.235
Water
4.18
Zinc
0.388
Specific Heat Data. Use the table to answer the following questions.
1. What substance in the table as the highest specific heat?
Chemistry
Ms. Boon
Name: _________________________________
Period: ______ Date: _______________
Example 1: A 100.0 g sample of water
was heated and the temperature increased
by 10 K. How much heat did the water
absorb?
Heat Transfer Calculations
Example 2: A 10.0 g sample of aluminum
was heated from 300 K to 325 K. How
much heat was absorbed by the
aluminum?
(1) A 2.0 g sample of lead was heated and
the temperature increased by 100 K. How
much heat did the lead absorb?
(2) A 50.0 g sample of carbon was heated
from 276 K to 376 K. How much heat was
absorbed by the carbon?
(3) A 40.0 mL sample of water (with a
mass of 40.0 g) was poured into the LA
river and its temperature dropped from 35
°C to 5 °C. How much heat was
released?
(4) A 20.0 g sample of silicon was heated
and the temperature increased by 110 K.
How much heat did the silicon absorb?
(5) A 500.0 mg sample of silver was
heated from 276 K to 376 K. How much
heat was absorbed by the silver?
(6) A 40.0 g gold nugget was dropped in
the Merced river and its temperature
dropped from 35 °C to 5 °C. How much
heat was released?
(7) A 23.0 g sample of water was heated
and the temperature increased by 50 K.
How much heat did the water absorb?
(8) A 60.0 g sample of chromium was
heated from 300 K to 350 K. How much
heat was absorbed by the chromium?
(9) 100 g of water was cooled from 370 K
to 273 K. How much heat was released?
What will happen to the water if it
continues to cool?
Example 3: A 0.5 g platinum ring was
dropped in the snow and its temperature
dropped from 35 °C to 0 °C. How much
heat was released?