Physical science ch 6
Does a hot object contain thermal energy, does it contain heat?
Hot objects contain thermal energy, not heat.
What is the reason for ice being less dense than water?
Ice is less dense than water due to its ice crystals that have open structures.
When disorder in a system increases, does entropy increase or decrease?
increase (entropy is a measure of disorder)
The high specific heat capacity of water has great importance in A. climates. B. cooling systems. C. ocean currents. D. All of the above.
A. All of the above
The first law of thermodynamics is a restatement of the A. conservation of energy. B. conservation of momentum. C. Both of these. D. None of the above.
A. conservation of energy
When a sample of 4°C water is cooled, it A. expands. B. contracts. C. remains unchanged. D. Not enough information.
A. expands (Parts of the water will crystallize and occupy more space)
The second law of thermodynamics tells us that the direction of heat flow is normally A. from hot to cold. B. from cold to hot. C. independent of temperature. D. present with external effort.
A. from hot to cold
When work is done on a system, compressing air in a tire pump, for example, the temperature of the system A. increases. B. decreases. C. remains unchanged. D. is no longer evident.
A. increases (in accord with the first law of thermodynamics, work input increases the energy of the system)
The greatest expansion of water occurs when A. it turns to ice. B. it cools at 4°C. C. it warms at 4°C. D. None of the above.
A. it turns to ice (sure, ice water expands a bit until it reaches 4 degrees Celsius, but the expansion of water when it turns to ice is much greater)
Hot sand cools off faster at night than plants and vegetation. This indicates the specific heat capacity for sand is A. less than that of plants. B. more than that of plants. C. likely the same as that of plants. D. unknown, because there is not enough information.
A. less than that of plants
In nature, high-quality energy tends to transform to A. lower-quality energy. B. entropy. C. time's arrow. D. equally useful forms.
A. lower-quality energy
Temperature
A measure of the hotness of substances, related to the average translational kinetic energy per molecule in a substance, measured in degrees Celsius, degrees Fahrenheit, or kelvins
1st law of thermodynamics
A restatement of the law of energy of conservation, usually as it applies to systems involving changes in temperature: the heat added to a system is equal to the system's gain in thermal energy plus the work that it does on its surroundings
The fact that gasoline will overflow from an automobile tank on a hot day is evidence that the expansion of gasoline is A. more than the tank material. B. about the same as the tank material. C. less than the tank material. D. nonexistent.
A. more than the tank material
When stringing telephone lines between poles in the summer, it is advisable to allow the lines to A. sag. B. be taut. C. be close to the ground. D. allow ample space for birds.
A. sag (telephone lines are longer in a warmer summer and shorter in a cold winter. Hence, they sag more on hot summer days than in winter. If the lines are not strung with enough sag in summer, they might contract too much and snap during the winter-especially when carrying ice)
There is twice as much molecular kinetic energy in 2 liters of boiling water as in 1 liter of boiling water. Which will be the same for both? A. Temperature. B. Thermal energy. C. Both of the above. D. None of the above.
A. temperature (average kinetic energy of molecules is the same, which means temperature is the same for both)
The kind of molecular motion having most to do with temperature is.. A. translational motion B. rotational motion. C. internal vibrational motion. D. longitudinal motion.
A. translation motion
Distinguish among a calorie, a Calorie, and a joule
All are units of energy A calorie is the energy needed to change the temperature of 1 gram of water by 1 degree Celsius; a Calorie is 1000 calories; a joule is the modern unit of energy, where 1 calories=4.19 J
You heat a half-cup of tea and its temperature rises by 4°C. How much will the temperature rise if you add the same amount of heat to a full cup of tea? A. 0°C. B. 2°C. C. 4°C. D. 8°C.
B. 2 degrees C
When a sample of 0°C water is heated, it first A. expands. B. contracts. C. remains unchanged. D. Not enough information.
B. contracts (Water continues to contract until it reaches a temperature of 4 degree Celsius. With further increase in temperature beyond 4 degrees Celsius, water then expands.
Aluminum has a specific heat capacity more than twice that of copper. If equal amounts of heat are given to equal masses of aluminum and copper, the metal that more rapidly increases in temperature is A. aluminum. B. copper. C. neither—actually, both will increase at the same rate. D. None of the above.
B. copper (copper has about half the "thermal inertia" of aluminum)
A metal ring has a gap in it, looking like the letter C. The ring expands when it is heated. Interestingly, the gap A. becomes narrower. B. expands also, as much as if metal filled the gap. C. expands, but less than if metal filled it. D. keeps its size, neither expanding or shrinking.
B. expands also, as much as if metal filled the gap
The same quantity of heat is added to different amounts of water in two equal-size containers. The temperature of the smaller amount of water A. decreases more. B. increases more. C. does not change. D. Not enough information.
B. increases more
Microscopic slush in water tends to make the water A. more dense. B. less dense. C. more slippery. D. warmer.
B. less dense
If a red hot thumbtack is immersed in warm water, the direction of heat flow will be from the A. warm water to the red hot thumbtack. B. red hot thumbtack to the warm water. C. no heat flow. D. Not enough information.
B. red hot thumbtack to the warm water
Absolute zero corresponds to a temperature of A. 0 K. B. -273°C. C. Both of the above. D. None of the above.
C. Both of the above (at absolute zero, a substance has no more energy to give up. 0 K = -273 degrees C)
In your room is a table, chair, and you. Which of these has a temperature normally greater than the temperature of the air in the room? A. Table. B. Chair. C. You. D. All have about the same temperature.
C. You
A bimetallic strip consists of a strip of metal composed of A. an alloy of brass and iron. B. braided brass and iron wires flattened into a strip. C. a brass strip welded along its length to an iron strip. D. a strip of metal with brass on one end, iron on the other end.
C. a brass strip welded along its length to an iron strip.
Thermal energy is normally measured in units of A. calories. B. joules. C. Both of the above. D. Neither of the above.
C. both of the above (calories and joules, like miles and meters, are different units for the same thing. 1 calories = 4.19 joules)
Water at 4°C will expand when it is slightly A. cooled. B. warmed. C. Both of the above. D. None of the above.
C. both of the above (the density of 4 degrees Celsius will also decrease when slightly cooled or warmed)
The thermal expansion of steel is about the same as that of A. water. B. air. C. concrete. D. All of the above.
C. concrete (the fact is important to civil engineers in the construction of concrete that is reinforced with steel rods)
Water at 4°C will sink to the bottom of a pond because A. of thermal currents. B. of the absence of thermal currents at low temperatures. C. like a rock, it is denser than surrounding water. D. of the presence of microscopic ice crystals.
C. like a rock, it is denser than surrounding water
Heat is simply another word for A. temperature. B. thermal energy. C. thermal energy that flows from hot to cold. D. radiant energy.
C. thermal energy that flows from hot to cold (be sure to distinguish between temperature, thermal energy, and flowing thermal energy)
To say that water has a high specific heat capacity is to say that water A. requires a lot of energy in order to increase in temperature. B. gives off a lot of energy in cooling. C. has a lot of "thermal inertia." D. All of the above.
D. All of the above
Which of these locations tends to have lower extremes in yearly temperature? A. Dallas, Texas. B. Sacramento, California. C. St. Louis, Missouri. D. Honolulu, Hawaii.
D. Honolulu, Hawaii (Hawaii is an island where climate is moderate, thanks to water's high specific heat)
The third law of thermodynamics has to do with A. the conservation of energy. B. the direction of time. C. energy dissipation. D. absolute zero.
D. absolute zero
2nd law of thermodynamics
Heat never spontaneously flows from a cold substance to a hot substance. Also, in natural processes, high-quality energy tends to transform into lower-quality energy-order tends to disorder.
How much energy can be removed from a system of 0 K?
No energy can be removed from a system at 0 K.
3rd law of thermodynamics
No system can reach absolute zero.
When can thermal energy move from lower to higher temperatures?
Only when external work is done on the system
Which warms faster when heat is applied: iron or silver? Which has the lower specific heat capacity?
Silver warms more quickly, which indicates that silver has the lower specific heat capacity
Enthalpy
The change in the thermal energy of a system plus the product of its pressure and volume
What role does temperature have in the direction of thermal energy flow?
The direction of thermal energy transfer is from objects at higher temperatures to lower temperatures.
How many joules are needed to change the temperature of 1 gram of water to 1 degree Celsius?
The energy needed is 4.19 J
Entropy
The measure of energy dispersal of a system. Whenever energy freely transforms from one form to another, the direction of transformation is toward a state of greater disorder and, therefore, toward one of greater entropy
Under what condition does a thermometer measure the temperature of its surroundings?
The necessary condition is thermal equilibrium, when both the thermometer and its surroundings have the same temperature
Specific heat capacity
The quantity of heat required to raise the temperature of a unit mass of a substance by 1 degree C.
Water at 4 C will expand when it is slightly a. cooled b. warmed c. both of these d. neither of these
c. both of these
Thermodynamics
The study of thermal energy and its relationship to heat and work.
Absolute zero
The temperature at which no further energy can be taken from a system
Heat
The thermal energy that flows from a substance of higher temperature to a substance of lower temperature, commonly measured in calories or joules.
Thermal energy
The total energy (kinetic plus potential) of the submicroscopic particles that make up a substance,
What is the relationship between water's high specific heat capacity and Europe's climate?
Thermal energy is carried in the Gulf Stream from tropical waters to the North Atlantic where it warms the otherwise cold climate
What are the temperatures for freezing water on the Celsius and Fahrenheit scales, respectively? For boiling water?
Water freezes at 0 degrees C and 32 degrees F, and boils at 100 degrees C and 212 degrees F
Your garage gets messier day by day. In this case, entropy is a. decreasing b. increasing c. hanging steady d. none of these
b. increasing
Absolute zero corresponds to a temperature of a. 0 K b. -273 C c. both of these d. neither of these
c. both of these
Thermal energy is normally measured in units of a. calories b. joules c. both of these d. neither of these
c. both of these
The motion of molecules that most affects temperature is a. translational motion b. rotational motion c. internal vibrational motion d. simple harmonic motion
a. translational motion
Heat energy travels from a. an object that has a greater amount of thermal energy to an object with lower thermal energy b. an object that has a higher temperature to an object with a lower temperature c. both of these d. none of these
b. an object that has a higher temperature to an object with a lower temperature
The specific heat capacity for aluminum is more than twice that of copper. If equal quantities of heat are given to equal masses of aluminum and copper, the metal that more rapidly increases in temperature is a. aluminum b. copper c. neither of these, both will crease in temp at the same rate d. none of these
b. copper
A bimetallic strip used in thermostats relies on the fact that different metals have different a. specific heat capacities b. thermal energies at different temps c. rates of thermal expansion d. all of these
c. rates of thermal expansion
Which two laws of thermodynamics are statements of what doesn't happen? a. the first and the second b. the first and the third c. the second and the third d. none of these; that is, they all state what does happen
c. the second and the third
Microscopic slush in water tends to make the water a. slipperier b. warmer c. more dense d. less dense
d. less dense