Iron specific heat

Calculate the mass loss or gain for each of the following processes (a) a 50.0-g block of iron (specific heat capacity, 0.45 J-(°C)"1-g 1) cools from 600°C to... 

Operational Characteristics. Oxygen generation from chlorate candles is exothermic and management of the heat released is a function of design of the total unit iato which the candle is iacorporated. Because of the low heat content of the evolved gas, the gas exit temperature usually is less than ca 93°C. Some of the heat is taken up within the candle mass by specific heat or heat of fusion of the sodium chloride. The reacted candle mass continues to evolve heat after reaction ends. The heat release duting reaction is primarily a function of the fuel type and content, but averages 3.7 MJ/m (100 Btu/fT) of evolved oxygen at STP for 4—8 wt % iron compositions. 

The specific heats of solids at low temperatures are appreciably less than at higher temperatures. A maximum specific heat has been observed in the case of iron at 740° and nickel at 320° (Lecher, 1908). Since these are the temperatures at which recalescence and loss of magnetic properties occur, the close relation of specific heat to molecular structure is evident. 

Fig. 5. Typical DSC-traces for the specific-heat jumps at the glass transition regions of iron-epoxy particulates, or E-glass fiber-epoxy composites and the mode of evaluation of ACp s...

Dowden and Reynolds (49,50) in further experimental work on the hydrogenation of benzene and styrene with nickel-copper alloys as catalysts, found a similar dependence. The specific activities of the nickel-copper alloy catalysts decreased with increasing copper content to a negligible value at 60% copper and 30-40% copper for benzene and styrene, respectively. Low-temperature specific heat data indicated a sharp fall (1) in the energy density of electron levels N(E) at the Fermi surface, where the d-band of nickel becomes filled at 60 % copper, and (2) from nickel to the binary alloy 80 nickel -)- 20 iron. Further work by these authors (50) on styrene hydrogenation with nickel-iron alloy... 

A 100.0 g sample of glycerol is put into the calorimeter calibrated in Problem 6, and its temperature is observed to be 20.5°C. Then 45.7 g of iron at 165.0°C are added to the glycerol, giving a resultant temperature of 37.4°C. Calculate the specific heat of the glycerol. (Use the approximate specific heat of iron.)... 

The heat capacity of a substance can be measured by a simple experiment. Add 50 g of water at 20.0°C to a calorimeter like that in Fig. 6.13. Then place 21 g of iron at 90.2°C into the calorimeter. Let s say that we measure a final temperature of 23.2°C. What is the specific heat capacity of iron ... 

STRATEGY All the heat lost by the iron is transferred to the water and the rest of the calorimeter. The heat lost or gained by each substance is equal to its heat capacity multiplied by the temperature rise or fall the heat capacity is the specific heat capacity multiplied by the mass. The heat capacity of the polystyrene cup is so small that we assume it can be neglected. Therefore, we can use Eq. 15 to write... 

The specific heat of iron shows a peak near the Curie temperature. From W. F. Hosford, Physical Metallurgy (Boca Raton, FL CRC Press, 2005), p. 331, figure 15.2. 

After finishing the measurement described in Example 5, the same iron resistor is placed in an insulated container with 75 g of an unknown substance. A current of 37 A through the resistor for 15 s raises the temperature of the system by 7.6°C. What is the specific heat of the unknown substance ... 

The total emissivity of the oxidised iron surface is 0.78 and both emissivity and absorptivity may be assumed independent of the surface temperature. (Density of iron = 7.2 Mg/m3. Specific heat capacity of iron = 0.50 kJ/kg K.)... 

In this case, n is a mass and C is the specific heat of iron ... 

The specific heat of iron is 0.11 cal/g °C thus, from the value of Sm determined experimentally, the unknown metal is iron. 

Consider a coffee-cup calorimeter filled with 250 g of distilled water at room temperature (25°C). Now, let s say you take a 5.00 g piece of iron that has been heated to 100°C by placing it in a container of boiling water for an extended period of time. If you place the iron into the room temperature water, you can probably imagine that the temperature of the iron will cool down while the temperature of the water will increase. The increase in the water s temperature and decrease in the iron s temperature are directly related to the transfer of heat from the iron to the water. The two will not stop changing temperature until they have both reached the same temperature. If the final temperature of the water is 25.2°C, what is the specific heat of the iron The specific heat of water is 4.18 J/g°C. 

The heat lost by the iron will equal the heat gained by the water, so we can use the specific heat equation to solve the problem ... 

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