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Specific Heat

Specific heat is the amount of heat per unit mass required to raise the temperature by one degree Celsius. The relationship between heat and temperature change can be seen below. However this relationship does not apply is a phase change occurs because the heat added or removed during a phase change does not change the temperature.

Q = cmΔT

Where Q is the heat added, c is the specific heat, m is mass, and ΔT is the change in temperature.

The specfic heat of water is 1 calorie/gram oC = 4.186 joule/gram oC. This is higher than any other common substance. As a result, water plays a very important role in temperature regulation. The specific heat per gram of water is higher than that for a metal.

The molar specific heat of most solids at room temperature and above is nearly constant. This comes from the Law of Dulong and Petit. At lower temperatures the specific heat drops as quantum processes become significant. The low temperature behavior is described by Einstein-Debye model of specific heat. 

Categories within Specific Heat

Enthalpy

Postings: 5

Enthalpy is the measure of the total amount of energy in a system.

Phase Changes

Postings: 17

A phase change is the transformation of a substance from one state to another.

Thermal Equilibrium

Postings: 6

Thermal equilibrium is the relationship between two respective physical bodies.

Entropy change: Water

5.2 Calculate the entropy change for each of the following: (a) 10g of steam at l00°C and a pressure of one atmosphere condensing into water at the same temperature and pressure. (The latent heat of vaporization of water is 22571 Jg^-1). (b) 10g of water at l00°C and a pressure of one atmosphere cooling to 0°C at the same

Simplify Representations of the Diesel Cycles

A simplified representation of the diesel cycle, with just air as the working substance. Show that the efficiency of the engine is: n = 1 - 1/y((1/rye-1/ryc)/(1/re-1/rc)) where re = V3/V2, the expansion ratio, and rc = V3/V1, the compression ratio. If re = 5, rc = 15 and y = 1.4, evaluate n. Notice that the compression r

Laboratory Problem

This is a problem we did in lab that dealt with measuring specific heat. Please provide answers along with solutions to the following questions. These problems mainly deal with specific heat capacity. See attached file for full problem description. A. What is the energy gained by water? Include measurement uncertainty?

Density, Pressure and Temperature

1. Spy balloon is to be constructed of a material with a mass of 0.5kg. it will be filled with helium and must be able to carry and instrument payload of 50kg at an altitude of 1000m where the density of the air is 1.16 kg/m^3. what mass of helium will be required. 2. If the temperature of gas (measured in K) is doubled a-

Hot iron horseshoe

A hot iron horseshoe (mass = 0.340 kg) which has just been forged, is dropped into 1.71 L of water in a 0.310 kg iron pot initially at 19.3oC. If the final equilibrium temperature is 24.8oC, calculate the initial temperature of the hot horseshoe (in Celsius).

Heat explained in this answer

How much heat is added to 500g of water to raise its temperature from 15 degrees C to 85 degrees C? a. 35 j b. 1.5 * 10^8j c. 1.5 * 10^5j d. 3.5 * 10^4j

Speed of sound, Bulk modulus of a gas

1) The bulk modulus of a gas varies with pressure. In the case of the air, the bulk modulus of air is equal to 1.40 times its pressure. the atmospheric pressure at sea level is 1.01 * 105 N/m2. The density of air at sea level is 1.20 kg/m3. For these conditions, what is the speed of sound as it passes through the air? a.328 m

Thermodynamics: Isochoric Process

A 2-kW baseboard electric resistance heater in a vacant room is turned on and kept on for 15 min. The mass of the air in the room is 75 kg, and the room is tightly sealed so that no air can leak in or out. The temperature rise of air at the end of 15 min is:

Calculate the rise in temperate after dropping a water filled balloon

A tourist drops a 1-liter water-filled balloon from the top of a monument (170m high). If air resistance is negligible and almost all the motion energy heats the water, find the increase in temperature of the water when it hits the pavement. (hint: equate mgh in joules to the quantity of heat mc (change) T and express c, the

Specific heat capacity

Question: A piece of glass has a temperature of 85.4C. Liquid that has a temperature of 43.0C is poured over the glass, completely covering it, and the temperature at equilibrium is 51.4C. The mass of the glass and the liquid is the same. Ignoring the container that holds the glass and liquid and assuming that the heat lost to

Specific/Heat Capacity - Extensive or Intensive Quality?

The heat capacity is defined as the amount of energy required to change the temperature of an object. The specific heat capacity is defined as the amount of energy required to change the temperature of an object per mole of the substance. a) Heat capacity is an Intensive quantity Extensive quantity b) Specific h

Quantum statistics

Consider a 2-level system with an energy splitting between the upper and lower level. Using Boltzmann statistics, show that the heat capacity of the 2-level system equals: (see attachment for equation) What happens in the limit of (see attachment for equation)

Heat Problem Set: Heat Capacity of Water

1. The air temperature above coastal areas is profoundly influenced by the large specific heat capacity of water. How large of a volume of air can be cooled by 1.0 C if energy is transferred as heat from the air to the water, thus increasing the temperature of 1.0 kg of water by 1.0 C? The specific heat capacity of air is appr

4 Physics Problems: Electrical Energy and Capacitance

See attached file. 1. On planet Tehar, the free fall acceleration is the same as that on Earth but there is also strong downward electric field with the field being uniform close to the planet's surface. A 2.00 kg ball having a charge of 5.00 mC is thrown upward at a speed of 20.1 m/s and it hits the ground after an interval

Proper Units

What amount of heat is required to change 10 grams of Ice at -10 degrees Celsius into steam at 120 degrees Celsius?

Determining the final mass of a cup using calorimetry.

A 150 gram Aluminum calorimeter cup contains 320 grams of water at 22 degrees Celsius. Steam at 100 degrees Celsius is routed into the calorimeter until the temperature of the cup and its contents reaches 50 degrees Celsius. What is the final total mass of the cup and its contents?