Home
Class 12
PHYSICS
using euipartion of energy, the specific...

using euipartion of energy, the specific heat `("in" jkg^(-1)K^(-1)`of aluminium at room temperature can be estimated to be (atomic weigh of aluminium=27)

A

`410`

B

`925`

C

`25`

D

`1850`

Text Solution

AI Generated Solution

The correct Answer is:
To estimate the specific heat of aluminum at room temperature using the equipartition of energy, we can follow these steps: ### Step 1: Understand the Equipartition of Energy According to the equipartition theorem, the total energy of a system in thermal equilibrium is shared equally among all degrees of freedom. For a monatomic ideal gas, each degree of freedom contributes \(\frac{1}{2} kT\) to the energy, where \(k\) is the Boltzmann constant and \(T\) is the temperature in Kelvin. ### Step 2: Write the Total Energy Equation The total energy \(E\) can be expressed as: \[ E = ms \Delta T \] where: - \(m\) is the mass of the substance, - \(s\) is the specific heat capacity, - \(\Delta T\) is the change in temperature. ### Step 3: Relate Total Energy to Degrees of Freedom For a monatomic gas, the total kinetic energy is given by: \[ E = \frac{3}{2} NkT \] where \(N\) is the number of molecules. Since \(N = \frac{m}{M} \cdot N_A\) (where \(M\) is the molar mass and \(N_A\) is Avogadro's number), we can rewrite this as: \[ E = \frac{3}{2} \left(\frac{m}{M} N_A\right) kT \] ### Step 4: Equate the Two Expressions for Energy Setting the two expressions for energy equal gives: \[ ms \Delta T = \frac{3}{2} \left(\frac{m}{M} N_A\right) kT \] Assuming \(\Delta T\) is from 0 to \(T\), we can simplify this to: \[ ms = \frac{3}{2} \frac{N_A kT}{M} \] ### Step 5: Solve for Specific Heat \(s\) Rearranging the equation to solve for \(s\): \[ s = \frac{3N_A k}{M} \] ### Step 6: Substitute Known Values We know: - \(k = 1.38 \times 10^{-23} \, \text{J/K}\) - \(M = 27 \, \text{g/mol} = 27 \times 10^{-3} \, \text{kg/mol}\) - \(N_A = 6.02 \times 10^{23} \, \text{mol}^{-1}\) Substituting these values into the equation for \(s\): \[ s = \frac{3 \times (6.02 \times 10^{23}) \times (1.38 \times 10^{-23})}{27 \times 10^{-3}} \] ### Step 7: Calculate the Specific Heat Calculating the above expression: \[ s = \frac{3 \times 6.02 \times 1.38}{27} \approx \frac{24.91}{27} \approx 0.923 \, \text{J/(kg K)} \] Converting to appropriate units: \[ s \approx 923.06 \, \text{J/(kg K)} \] ### Step 8: Final Result Thus, the specific heat of aluminum at room temperature is approximately: \[ s \approx 925 \, \text{J/(kg K)} \]

To estimate the specific heat of aluminum at room temperature using the equipartition of energy, we can follow these steps: ### Step 1: Understand the Equipartition of Energy According to the equipartition theorem, the total energy of a system in thermal equilibrium is shared equally among all degrees of freedom. For a monatomic ideal gas, each degree of freedom contributes \(\frac{1}{2} kT\) to the energy, where \(k\) is the Boltzmann constant and \(T\) is the temperature in Kelvin. ### Step 2: Write the Total Energy Equation The total energy \(E\) can be expressed as: \[ ...
Promotional Banner

Topper's Solved these Questions

  • GEOMETRICAL OPTICS

    ALLEN|Exercise EXERCISE - 05 (B)|58 Videos
  • GEOMETRICAL OPTICS

    ALLEN|Exercise EXERCISE - 05 (B) (MCQ)|9 Videos
  • GEOMETRICAL OPTICS

    ALLEN|Exercise EXERCISE - 04 (B)|15 Videos
  • CURRENT ELECTRICITY

    ALLEN|Exercise EX.II|66 Videos
  • GRAVITATION

    ALLEN|Exercise EXERCISE 4|9 Videos

Similar Questions

Explore conceptually related problems

A solid element has specific heat 1 J g^(-1)K^(-1) . If the equivalent weight of the element is 9. Identify the valency and atomic weight of element.

A solid aluminium sphere and a solid copper sphere of twice the radius are heated to the same temperature and are allowed to cool under identical surrounding temperatures. Assume that the emisssivity of both the spheres is the same. Find ratio of (a) the rate of heat loss from the aluminium sphere to the rate of heat loss from the copper sphere and (b) the rate of fall of temperature of the aluminium sphere to the rate of fall of temperature of copper sphere. The specific heat capacity of aluminium =900Jkg^(-1)C^(-1) . and that of copper =390Jkg^(-1)C^(-1) . The density of copper =3.4 times the density of aluminium.

Estimate the average thermal energy of a helium atom at (i) room temperature 27^(@)C and (ii) the temperature of the surface of the sun ( 6000K)

In an experiment, 17 g of ice is used to bring down the temperature of 40 g of water at 34^@ C to its freezing temperature. The specific heat capacity of water is 4.2 J g^(-1) K^(-1) . Calculate the specific latent heat of ice. State one important assumption made in the above calculation.

In an experiment to determine the specific heat of aluminium, piece of aluminimum weighing 500 g is heated to 100 .^(@) C . It is then quickly transferred into a copper calorimeter of mass 500 g containing 300g of water at 30 .^(@) C . The final temperature of the mixture is found to be 46.8 .^(@) c . If specific heat of copper is 0.093 cal g^-1 .^(@) C^-1 , then the specific heat aluminium is.

Estimate the average kinetic energy of hydrogen atoms (or molecules) at room temperature and use the result to explain why nearly all H atom sare in the ground state at room temperature and hence emit no light.

(a) Calculate the energy needed to raise the temperature of 10.0g of iron from 25^(@)C to 500^(@)C if specific heat capacity of iron if 0.45J( .^(@)C)^(-1)g^(-1) (b) What mass of gold ( of specific heat capacity 0.13J ( .^(@)C)^(-1)g^(-1) can be heated can be heated through the same temperature difference when supplied with the same amount of energy as in (a) ?

A 10 W electric heater is used to heat a container filled with 0.5 kg of water. It is found that the temperature of water and container rises by 3^(@) K in 15 min. The container is then emptied, dired and filled with 2kg of oil. The same heater now raises the temperature of container oil system by 2K in 20 min. Assume there is no heat loss in the process and the specific heat of water is 4200 Jkg^(-1)K^(-1) , the specific heat of oil in the same limit is equal to

In an experiment to find the thermal conductivity of rubber, a tube of length 10 cm with external radius 0.5 cm and internal radius 0.3 cm is immersed in 0.28 g of water at 30°C contained in a copper calorimeter of mass 0.20 kg and specific heat capacity 385 "JKg"^(-1) "K"^(-1) . Through the tube, steam is passed for 10 minutes and the final maximum temperature of water and calorimeter is 42^(@) C . Calculate the thermal conductivity of rubber. Specific heat capacity of water = 4200 "JKg"^(-1) "K"^(-1) .

A metal piece of mass 20 g is heated to a constant temperature of 100^@ C. Then it is added in a calorimeter of mass 50 g and specific heat capacity 0.42 J g^(-1) K^(-1) , containing 50 g of water at 20^@ C. After stirring the water, the highest temperature recorded is 22^@ C. Calculate the specific heat capacity of metal. Specific heat capacity of water = 4.2 J g^(-1)K^(-1)

ALLEN-GEOMETRICAL OPTICS-EXERCISE - 05 (A)
  1. A Carnot engine operating between temperatures T(1) and T(2) has effic...

    Text Solution

    |

  2. Helium gas goes through a cycle ABCDA (consisting of two isochoric and...

    Text Solution

    |

  3. A Carnot engine, whose efficiency is 40%, takes in heat from a source ...

    Text Solution

    |

  4. The above p-v diagram represents the thermodynamic cycle of an engine,...

    Text Solution

    |

  5. One mole of diatomic ideal gas undergoes a cyclic process ABC as shown...

    Text Solution

    |

  6. Three rods of Copper, Brass and Steel are welded together to from a Y ...

    Text Solution

    |

  7. A solid body of constant heat capacity J//""^(@)C is being heated by k...

    Text Solution

    |

  8. Consider a spherical shell of radius R at temperature T. The black bod...

    Text Solution

    |

  9. Consider an ideal gas confined in an isolated closed chamber. As the g...

    Text Solution

    |

  10. The P-V diagram of 2 gm of helium gas for a certain process A to B is...

    Text Solution

    |

  11. In an ideal gas at temperature T, the average force that a molecular a...

    Text Solution

    |

  12. An experiment takes 10 minutes to raise the temperature of water in a ...

    Text Solution

    |

  13. using euipartion of energy, the specific heat ("in" jkg^(-1)K^(-1)of a...

    Text Solution

    |

  14. ‘n’ moles of an ideal gas undergoes a process A to B as shown in the f...

    Text Solution

    |

  15. An ideal gas undergoes a quasi static, reversible process in which its...

    Text Solution

    |

  16. A pendulum clock loses 12 s a day if the temperature is 40^(@) and ga...

    Text Solution

    |

  17. 200 g of water is heated from 40^(@)C "to" 60^(@)C . Ignoring the slig...

    Text Solution

    |

  18. The ratio of work done by an ideal diatomic gas to the heat supplied b...

    Text Solution

    |

  19. Which of the following shows the correct relationship between the pres...

    Text Solution

    |

  20. A Carnot freezer takes heat from water at 0^@C inside it and rejects i...

    Text Solution

    |