specific heat capacity

• What concept relates internal energy to temperature?

  Specific heat capacity
• What is internal energy?

  Total energy stored by particles in a substance
• What are the two parts of internal energy?

  Potential energy stores and kinetic energy stores
• Which type of energy is important for temperature changes?

  Kinetic energy
• How does heating a substance affect its internal energy?

  It increases the kinetic energy of particles
• What does temperature measure?

  Average internal energy of a substance
• Why do some materials require more energy to increase temperature?

  They have higher specific heat capacities
• How much energy does water require to warm 1 kg by 1°C?

  4200 joules
• How much energy does mercury require to warm 1 kg by 1°C?

  139 joules
• What is specific heat capacity?

  Energy needed to raise temperature of 1 kg by 1°C
• What happens when 1 kg of water cools by 1°C?

  It releases 4200 joules of energy
• What is the equation for change in internal energy?

  ΔU = m × c × Δθ
• How do you find the change in temperature?

  Energy / (mass × specific heat capacity)
• What is the mass of water in kilograms if it is 800 grams?

  0.8 kilograms
• How do you convert 20 kilojoules to joules?

  20,000 joules
• What is the temperature change for 20,000 joules of energy to 0.8 kg of water?

  5.95 degrees Celsius
• What is the final temperature of water if the initial temperature is 20°C and the change is 5.95°C?

  25.95 degrees Celsius
• Why might the temperature not increase as much in real life?

  Energy is lost to surroundings as heat
• What precautions should be taken during the experiment to measure temperature changes?

  • Use a lid to minimize heat loss
  • Insulate the container well
• What are the key differences in specific heat capacities of water and mercury?

  • Water: 4200 joules/kg/°C
  • Mercury: 139 joules/kg/°C
  • Water requires more energy to heat