Question

какое количество теплоты необходимо сообщить льду массой m = 1,5 кг, находящемуся при температуре t = -20 С, чтобы нагреть его до температуры плавления и полностью расплавить?

Answer 1

Q=cmΔt+ λm=2100*1.5*20+ 330000*1.5=63000+495000=558(КДж)

Answer 2

Calculating Heat Required to Melt Ice

To calculate the amount of heat required to melt ice, we can use the formula:

Q = m * L + m * c * ΔT

Where: - Q = heat required - m = mass of the ice (1.5 kg) - L = latent heat of fusion for ice - c = specific heat capacity of ice - ΔT = change in temperature

First, let's find the latent heat of fusion for ice and the specific heat capacity of ice.

The latent heat of fusion for ice is the amount of heat required to change 1 kg of ice at 0°C to water at 0°C. It is approximately 334 kJ/kg.

The specific heat capacity of ice is the amount of heat required to raise the temperature of 1 kg of ice by 1°C. It is approximately 2.09 kJ/kg°C.

Now, we can calculate the heat required to melt the ice.

Q = (1.5 kg) * (334 kJ/kg) + (1.5 kg) * (2.09 kJ/kg°C) * (0°C - (-20°C))

Q = 501 kJ + 62.65 kJ

Q = 563.65 kJ

So, the amount of heat required to melt 1.5 kg of ice at -20°C and raise it to its melting point is approximately 563.65 kJ.