Section 5.2 - Thermal Content Flashcards Preview

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Flashcards in Section 5.2 - Thermal Content Deck (14)
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1

Define internal energy

Sum of the individual potential and kinetic energies of all molecules within the body

2

State the first law of thermodynamics

The change of internal energy of the object is equal to the total energy transfer due to work done and heating

3

Define specific heat capacity

The energy required to change the temperature of 1kg of the substance by 1K without changing state

4

Describe the experiment to measure the specific heat capacity of a metal

Metal block of known mass in an insulated container. Electrical heater inserted into a hole in the metal, thermometer into another.
Measure the temperature change over a given time

5

Which measurements are used to measure specific heat capacity of a metal, and how?

Heater's current (I)
Heater's pd (V)
Time of heating (t)
Temperature change (ΔT)
mcΔT=IVt (rearrange for c)

6

State Boyle's law

When a fixed mass of gas is reduced in volume by a compressing piston, the pressure inside the piston increases

7

Explain why Boyle's law is true

Gas particles all in motion
Pressure exists from surface collisions exerting a force
Volume decreases
Collisions occur more frequently
Pressure increases

8

State Charles' law

For a fixed mass of an ideal gas at constant pressure, its volume is directly proportional to its absolute temperature

9

State the pressure law

For a fixed mass of an ideal gas at constant volume, its pressure is directly proportional to its absolute temperature

10

Define Avogadro constant

The number of atoms in exactly 12g of carbon-12

11

Define molar mass

The mass of 1 mol of the substance

12

What are the five assumptions that are made for the kinetic theory equation?


Molecules are point molecules
No attractive forces between molecules
Molecules move in continual random motion
All collisions are elastic
Time of collisions is negligible

13

Define molar heat capacity

The energy required to change 1 mol of gas by 1K

14

Define heat capacity

The energy required by an entire object to change temperature by 1K