Variables
This variable represents heat added or removed
Q
This is the formula that includes heat, specific heat, mass, and temperature change
Q = mcAT
How do you know when to use the Q=MCAT formula?
Water
This phase change occurs when there is snow on the ground, and the weather begins to warm up!
melting
This variable represents mass
m
What is the change in temperature of an object whose initial temperature is 40 °C and reaches a final temperature of 65 °C?
15 °C
What are the units for specific heat?
J /g C
J /g K
This phase change occurs when you have an ice cold beverage outside in the hot sun!
condensation
This variable represents specific heat capacity
How much heat must be absorbed by 375 grams of water to raise its temperature by 25°C? (The specific heat of water is 4.18 J/g°C.)
39187.5 J
How do you know when to use the heat of fusion (Hf) formula?
Problem should mention freezing or melting, no temperature change
This phase change occurs as you begin boiling pasta and feel steam coming off the top of the pot!
evaporation/vaporization
delta T
1840 J of heat is needed to warm 50 g of iron from 20 °C to 100 °C. What is the specific heat of iron?
0.46 J/g°C
What table(s) in the Reference packet do we use to find the values for heat of fusion and heat of vaporization?
Table B
Which phase change is used to create a spooky, foggy effect in movies and haunted houses?
sublimation