Specific heat capacities:

copper | 400Jkg^{-1}K^{-1} | |

iron | 460Jkg^{-1}K^{-1} | |

water | 4200Jkg^{-1}K^{-1} | |

ice | 2100Jkg^{-1}K^{-1} |

Specific latent heat of fusion of ice = 3·3×10

^{5}Jkg^{-1}
Molar heat capacities of a diatomic ideal gas:

C

C

_{v}= 12·5J(molK)^{-1}and C_{p}= 20·8J(molK)^{-1}**Question 1**

A piece of metal of mass 0·2kg is heated to a temperature of 200°C. It is then put into 0·2kg of water at 20°C in a container of negligible heat capacity. The "final" temperature, after stirring, is 40°C. Calculate the specific heat capacity of the metal. |

**Question 2**

A piece of ice at -20°C is put into a copper calorimeter of mass 0·2kg which contains 0·15kg of water at 20°C. The water is stirred until all the ice has melted. At this time the temperature of the water (and calorimeter) is 15°C. Calculate the mass of the piece of ice. |

**Question 3**

A refrigerator is capable of removing 50J of heat per second from a container of water. How long will it take to change 2kg of water at 10°C into ice at -5°C? Assume that the rate of removal of heat remains constant and that the container has negligible heat capacity. Are these assumptions likely to be valid in practice? |

**Question 4**

A piece of metal of mass 100g, has a temperature of 100°C. It is put into 100g of water at 20°C in a container of negligible heat capacity. After stirring, the maximum temperature of the "mixture" (metal and water) is 27·5°C. Calculate the specific heat capacity of the metal. |

**Question 5**

How long will it take to change the temperature of 200kg of water from 15°C to 40°C, using a heater of power 3kW. Assume that all the thermal energy remains in the water. |

**Question 6**

The diagram below show a cross-section view of a sheet of metal (of thermal conductivity, k) covered on each side by a layer of plastic of thermal conductivity k/1000. The lower face of the plastic is maintained at a steady temperature, T_{4} = 150°C. The top surface is maintained at a steady temperature, T_{1} = 20°C. Calculate the temperatures of the surfaces of the metal, T_{2} and T_{3}. Assume that the heat lost through the sides of the metal (and plastic) is negligible. |

**Question 7**

A rectangular piece of metal is 20·00cm×30·00cm, at 20°C. The linear expansivity (linear expansion coefficient) for the metal is = 1×10^{-6}°C^{-1}. | |||

Calculate | |||

a) | the surface area, A_{o}, of the piece of metal at 20°C (yes I know its difficult, but try…) | ||

b) | the lengths of the sides of the piece of metal at 80°C | ||

c) | the surface area, A, of the piece of metal at 80°C | ||

d) | the value of the quantity | ||

Compare this figure with the value of . |

**Question 8**

a) | Considering question 9 part d), define, in words, the area expansion coefficient of a substance and state how it is related to the linear expansion coefficient. |

b) | Suggest a definition of the volume expansion coefficient of a substance and predict how it might be related to the linear expansion coefficient. |

**Question 9**

Two moles of an ideal gas are heated at a constant pressure of 10^{5}Pa. The temperature of the gas increases from 293K to 313K. | |

Calculate | |

a) | the total amount of heat supplied |

b) | the change in internal energy of the gas |

c) | the work done by the gas during expansion |

d) | the change in volume of the gas. |

**Question 10**

20mols of an ideal gas are in a cylinder of initial volume 0·5m^{3} at a temperature of 27°C. The gas is supplied with 10000J of heat at constant pressure. Calculate | |

a) | the final temperature of the gas |

b) | the final volume of the gas |

c) | the change in internal energy of the gas |