How many grams of coffee must evaporate from 650 g of coffee in a 160 g...

 

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How many grams of coffee must evaporate from 650 g of coffee in a 160 g glass cup to cool the coffee and the cup from 95.0C to 20.0C? Assume the coffee has the same thermal properties as water and that the average heat of vaporization is 2,340 kJ/kg (560 cal/g). Neglect heat losses through processes other than evaporation, as well as the change in mass of the coffee as it cools. x g Do the latter two assumptions cause your answer to be higher or lower than the true answer? O My answer is lower than the true answer because, if coffee loses heat in other ways and its mass decreases, it will need more evaporation for the same temperature drop. My answer is higher than the true answer because, if coffee loses heat in other ways and its mass decreases, it will need less evaporation for the same temperature drop. O My answer is higher than the true answer because, if coffee loses heat in other ways and its mass decreases, it will need more evaporation for the same temperature drop. O My answer is lower than the true answer because, if coffee loses heat in other ways and its mass decreases, it will need less evaporation for the same temperature drop. How many grams of coffee must evaporate from 650 g of coffee in a 160 g glass cup to cool the coffee and the cup from 95.0C to 20.0C? Assume the coffee has the same thermal properties as water and that the average heat of vaporization is 2,340 kJ/kg (560 cal/g). Neglect heat losses through processes other than evaporation, as well as the change in mass of the coffee as it cools. x g Do the latter two assumptions cause your answer to be higher or lower than the true answer? O My answer is lower than the true answer because, if coffee loses heat in other ways and its mass decreases, it will need more evaporation for the same temperature drop. My answer is higher than the true answer because, if coffee loses heat in other ways and its mass decreases, it will need less evaporation for the same temperature drop. O My answer is higher than the true answer because, if coffee loses heat in other ways and its mass decreases, it will need more evaporation for the same temperature drop. O My answer is lower than the true answer because, if coffee loses heat in other ways and its mass decreases, it will need less evaporation for the same temperature drop.