Heating Curve for Water Notes

1. AGENDA:
PHET BUILD A
MOLECULE
WATER NOTES
TEST CORRECTIONS

2. PHASE CHANGES
• MELTING
• FREEZING
• VAPORIZATION (OR
EVAPORATION)
• CONDENSATION
• SUBLIMATION
• DEPOSITION
SOLID  LIQUID
LIQUID  SOLID
LIQUID  GAS
GAS  LIQUID
SOLID  GAS
GAS  SOLID

3. HEAT GAIN, HEAT LOSS
• ENDOTHERMIC CHANGE
• ENDOTHERMIC CHANGE – SYSTEM
ABSORBS HEAT
• EXOTHERMIC CHANGE
• EXOTHERMIC CHANGE – SYSTEM
RELEASES HEAT

4. HEATING CURVE FORWATER
120 °C
STEAM
(GAS)
100 °C WATER→ STEAM
50°C WATER(LIQUID)
0 °C SOLID→ LIQUID
-10 °C ICE (SOLID)
HEAT ADDED→

5. ENDOTHERMIC OREXOTHERMIC?
120 °C
STEAM
(GAS)
100 °C WATER→ STEAM
50°C WATER(LIQUID)
0 °C SOLID→ LIQUID
-10 °C ICE (SOLID)
HEAT ADDED→

6. HEATING CURVE
THE FLAT LINES ON A HEATING CURVE REPRESENT
 A CHANGE OF STATE
THE SLOPEDLINES ON A HEATING CURVE
REPRESENT
 A TEMPERATURE CHANGE
KEY TEMPERATURES FORWATER FREEZING - 0
ºC ANDBOILING - 100º C

7. HEATING CURVE
WHY DOTHE FLAT LINES EXTENDOVERA LONG
PERIODOF TIME?
 WATERHAS A HIGHSPECIFIC HEAT –
MEANING IT ABSORBS HEAT FORA LONG TIME
BEFORE IT CHANGES STATE/PHASE

8. COOLING CURVE
USING THE HEATING CURVE OF WATERAS
A GUIDE, DRAWA COOLING CURVE FOR
WATERBEGINNING WITHSTEAMAT 110°C
ANDENDING AT -20°C.

9. LEARNING CHECK1
A. WATERCONDENSES AT A TEMPERATURE OF
1) 0°C 2) 50°C 3) 100°C
B. AT A TEMPERATURE OF 0°C, WATER
1) FREEZES 2) MELTS 3) CHANGES TOA GAS
C. WHEN A GAS CONDENSES, HEAT IS
1) RELEASED 2) ABSORBED
D. FREEZING IS
1) ENDOTHERMIC 2) EXOTHERMIC

10. SOLUTION 1
A. WATERCONDENSES AT A TEMPERATURE OF
3) 100°C
B. AT A TEMPERATURE OF 0°C, WATER
1) FREEZES 2) MELTS
C. WHEN A GAS CONDENSES, HEAT IS
1) RELEASED
D. FREEZING IS
2) EXOTHERMIC

11. LEARNING CHECK2
IS ENERGY ABSORBED(1) ORRELEASED(2) IN EACHOF
THE FOLLOWING:
____A. ICE TOLIQUIDWATER
____B. WATERVAPORTO RAIN
____C. WATERTO ICE
WHEN IT RAINS, THE AIRBECOMES
1) WARMER 2) COOLER 3) DOES NOT CHANGE

12. SOLUTION 2
IS ENERGY ABSORBED(1) ORRELEASED(2) IN EACHOF THE
FOLLOWING:
A. ICE TOLIQUIDWATER
1
B. WATERVAPORTO RAIN
2
C. WATERTOICE
2
WHEN IT RAINS, THE AIRBECOMES
1) WARMER

13. LEARNING CHECK 3
COMPLETE USINGTHE TERMS GAINS OR
LOSES
IN THE COOLINGCOILS OF A REFRIGERATOR,
LIQUIDFREON ___________ HEAT FROMTHE
FOODANDCHANGES TOA GAS
FOOD___________HEAT ANDBECOMES
COLDER
IN THE BACKOF THE REFRIGERATOR, FREON
_________ HEAT ANDCONDENSES BACKTOA