Question

Calculate the amount of heat required to sublime 50 grams of dry ice (CO2) at -78.5°C given that the heat of sublimation for CO2 is 25.2 kJ/mol.

Answer 1

To calculate the amount of heat required to sublime 50 grams of dry ice, we need to first determine the number of moles of CO2 present in 50 grams. The molar mass of CO2 is 12.01 g/mol  for carbon  + 2 * 16.00 g/mol  for oxygen  = 44.01 g/mol.Number of moles of CO2 = mass / molar massNumber of moles of CO2 = 50 g / 44.01 g/mol = 1.136 molesNow, we can use the heat of sublimation  25.2 kJ/mol  to calculate the amount of heat required to sublime 1.136 moles of CO2.Heat required = number of moles * heat of sublimationHeat required = 1.136 moles * 25.2 kJ/mol = 28.62 kJTherefore, the amount of heat required to sublime 50 grams of dry ice at -78.5C is 28.62 kJ.