How much energy in mega joules is needed to convert 7 kilograms of ice at -9 c to water at 0 c?

To calculate the energy required to convert 7 kg of ice at -9°C to water at 0°C, we need to consider two steps: heating the ice to 0°C and then melting the ice. The specific heat capacity of ice is about 2.09 J/g°C, so heating 7 kg (7000 g) of ice from -9°C to 0°C requires approximately 130,230 J (or 0.130 MJ). The latent heat of fusion for ice to water is about 334 J/g, so melting 7 kg of ice requires about 2,338,000 J (or 2.338 MJ). Therefore, the total energy required is approximately 2.468 MJ.