Physical Science Chap. 6 Thermal
19.) How does thermal energy flow?
(For substances in thermal contact)From the higher temperature substance into the lower temperature until thermal equilibrium is reached. {Thermal energy never flows unassisted from a lower temperature substance into a higher temperature one.}
22.) What is a kilo calorie?
1 kcal = 1000 cal
20.) Convert joules to calories.
4.19 J = 1 Calorie
21. ) How much heat is needed to change 1 g of water by 1 Celsius?
4.19 joule/1 calorie
Q3.) The amount of heat transferred to a system can be measured in _______.
Either calories or joules
14.) What happens to gas when temperature changes?
Gases expand when heat and contract when cooled.
26.) What is the second law of thermodynamics?
Heat never spontaneously flows from a cold substance to a hot substance.
3.) How temperature measured in gases?
How fast the gas particles are bouncing back and forward.
5.) How is temperature measured in solids?
How fast the particles move as they vibrate and jiggle in place.
4.) How is temperature measured in liquids?
How fast they slide and jiggle past each other.
25.) What are the 2 possible effect does heat have when added to something?
Increase the system thermal energy or enable it to do work on its surroundings (or both)
8.) Define temperature?
a per-particle property, the average Kinetic Energy per particle. Measured in degrees.
12.) What happens to thermal motion increases?
A solid object first melts,and then becomes liquid, vaporize, molecules break apart (dissociate) into atoms, the atoms will lose some or all of their electrons, thereby forming a cloud of electrically charged particles(a plasma)
Q6.) The rock-bottom coldest an object can hope to reach is _______.
Absolute zero and -273degrees Celsius
10.) Define Thermal Energy
Also called internal energy
Q10.) When the temperature of a strip of iron is increased, the length of the strip _______.
Also increases
Q9.) What does specific heat capacity measure?
Any substance is defined as the quantity of heat required to change the temperature of a unit mass of the substance by 1 degree Celsius. **AKA thermal inertia(inertia: resistance to change in its state of motion)**
Thermal Expansion
As the temperature of a substance increases, its molecules jiggle faster and move farther apart. *Liquids expand more than solids
Q1.) Temperature is generally proportional to a substance's _______.
Average translational kinetic energy of its particles
Why is water's specific heat capacity important?
Because of its transparency it takes more energy to warm water, it has a much higher capacity for storing thermal energy than almost any other sustance. It absorbs a great quantity of heat for small increases in temperature Water has various ways that energy can be stored w/o increasing translational kinetic energy
Q5.) As entropy in a system increases, energy in the system _______.
Becomes less ordered
Q4.) The second law of thermodynamics tells us that heat flows from _______.
Cold to hot with work input
What happens to water between 0 degrees and 4 degree Celsius
Contraction and expansion at the same time Volume decrease when warm Volume increases when frozen
Q17.) To say that water has a high specific heat capacity is to say that water ______. A. requires a lot of energy for an increase in temperature B. releases a lot of energy in cooling. C. absorbs a lot of energy for an increase in temperature. D. all of the above
D. All of the above Requires a lot of energy for an increase in temperature, Releases a lot of energy in cooling, Absorbs a lot of energy for an increase in temperature.
Q20.) As a hot iron ring cools, the diameter of the hole
Decreases
Equal masses of different materials require_____.
Different quantities of heat to change their temperatures by a specific number of degrees
15.) What is the absolute temperature scale?
Kelvin scale (0K), no negative numbers. temperature divisions are identical to the divisions on the Celsius scale. 273K melting point of ice/ 373K boiling point of water
Q12.) Microscopic slush in water tends to make the water _______.
Less dense or crowed (bloats) *Volume is slightly increased Ice is less dense than water
Q8.) Hot sand cools off faster at night than do plants and vegetation. Hence, the specific heat capacity for sand is _______.
Less than that of plants and vegetation
11.) Define Absolute zero?
Lower limit of temperature -273 Degrees Celsius. Molecules have lost all available kinetic energy. **No more energy can be lost therefore it cant get any colder**
Q19.) If the specific heat capacity of water were lower than it is, ponds in the cold of winter would be_______.
More likely to freeze
23.) Define thermodynamics?
Movement of heat.
17.) Which is larger a kelvin or Celsius?
Neither, they are equal.
CHAPTER 6
QUIZ
7.) Define thermal energy?
Relating to the sum total kinetic energy of all the particles in your sample.
Q7.) To say that water has a high specific heat capacity means that water _______.
Releases a lot of energy in cooling, absorbs a lot of energy for a small increase in temperature, requires a lot of energy in order to increase in temperature.
Q18.) Which law of thermodynamics addresses the direction of heat flow?
Second law {High Quality of energy, as energy becomes more diffuse and ultimately degenerates into waste} high energy transformers into lower quality energy
18.) A sample of hydrogen gas has a temperature of 0 degrees Celsius. If the gas is heated until hydrogen molecules have doubled their kinetic energy, what is its temperature?
The 0 degree Celsius gas has an absolute temperature of 273K. Twice as much kinetic energy means that it has twice the absolute temperature, or two times 273 K. This would be 546K, or 273 Celsius
2. ) Temperature is proportional to what?
The average transitional (to and fro linear motion) kinetic energy per particle that makes up the substance.
24.) What is first law of thermodynamics?
The law of energy conservation applied to thermal systems. When heat flows to or from a system, the system gains or loses an amount of energy equal to the amount of heat transferred. { Heat added = Increase in thermal energy + External work done by the system}
6.) If someone has a cup of hot water and then pours half of the water onto the floor what would be the result?
The remaining water in the cup will not change its temperature, half the thermal energy will remain. Therefore their are only half as many molecules as before.
16.) Define heat?
Thermal (energy) in transit. Measured in joules or calories. [Thermal energy transferred from one thing to another due to a temperature difference. {Matter only contains thermal energy Not heat. Heat ceases when transferred from one object to another}]
1.) What happens when you touch ice?
Thermal energy passes from your had to the colder ice.
Q2.) Heat is simply another word for _______.
Thermal energy that flows from hot to cold
13.) Define plasma?
They exist in stars, temperature has no upper limit.
Q14.) The thermal energy in a substance is related mostly to the________.
Total kinetic energy of particles.
9.) Define thermal equilibrium?
When the object and the thermometer have the same average kinetic energy per particle