A calorimeter of water equivalent 15 g contains 165 g of water at 25°C. Steam at 100°C is passed through the water for some time. The temperature is…

A calorimeter of water equivalent 15 g contains 165 g of water at 25°C. Steam at 100°C is passed through the water for some time. The temperature is increased to 30°C and the mass of the calorimeter and its contents is increased by 1.5 g. Calculate the specific latent heat of vaporization of water. [Specific heat capacity of water = 4.2 Jg⁻¹K⁻¹]

  1. 2386 Jg⁻¹
  2. 3780 Jg⁻¹
  3. 2226 Jg⁻¹ ✓
  4. 3339 Jg⁻¹

Explanation

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Electricity generation: mainly gas-fired plants and hydro (Kainji, Shiroro, Jebba dams). Chronic power shortages hamper industry and daily life. Many rely on generators despite high fuel costs.

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