Section 4: Heat & Temp

Question 1

What is ºF to ºC?

Answer 1

ºC = (5/9)(ºF - 32)

Question 2

What is ºC to K ?

Answer 2

K = ºC + 273.15

Question 3

What is Thermal Expansion Equation ?

Answer 3

L = L₀[1 + α∆T]

Question 4

How is total heat energy of this problem found ?

Suppose you want to raise the temperature of a 0.21-kg piece of ice from -20.0°C to 130°C. The heat of fusion is Lf = 334kJ/kg, and the heat of vaporization is Lv = 2256kJ/kg. In this problem, take 1520J/kg⋅°C as the specific heat of steam (c₂), and 2090J/kg⋅°C as the specific heat of ice (c₁).

Take (c) as the specific heat of water 4184J/kg°C

Answer 4

This block of ice goes through two phase changes: Solid-Liquid (Lf) and Liquid to Gas (Lv). so we use out two equations:

Q = mc∆T & Q = mL; to solve the total amount of energy produced:

Q₁ = mc₁∆T₁
Q₂ = mLf
Q₃ = mc∆T₂
Q₄ = mLv
Q₅ = mc₂∆T₃

Then find the energy by summing these values: ΣQ

Question 5

What is specific heat of water at liquid phase ?

Answer 5

c = 4184J/kg°C