A customer orders 200ml of Sumatran coffee at precisely 60.0°C. You then need to drop the temperature of the coffee, initially at 90.0°C, to the ordered temperature. In order to simplify the calculations, you will start by assuming that coffee has the specific heat and density as if water. In the following parts, you will remove these simplifications. Solve now this problem assuming the density is 1.000 g/ml for coffee and its specific heat capacity is 4.184 J/(g ºC). If you had used ice cubes to cool the coffee, your calculation of q would have been a two- step process: (1) the ice at 0 oC first has to melt (energy added to go from solid to liquid; and then (2) to warm the liquid from 0 oC to the final temperature where q = mice cice + mwater cwater ∆T where cice = 2.11 J/ g . oC cwater = 4.184 J/ g . oC (Note: there is no ∆T for the first step since melting of the ice occurs at 0 oC, no temperature change) What mass of ice would you need to use to achieve the same result (qice = qmilk)? (Note: mice = mwater)
Thermochemistry
Thermochemistry can be considered as a branch of thermodynamics that deals with the connections between warmth, work, and various types of energy, formed because of different synthetic and actual cycles. Thermochemistry describes the energy changes that occur as a result of reactions or chemical changes in a substance.
Exergonic Reaction
The term exergonic is derived from the Greek word in which ‘ergon’ means work and exergonic means ‘work outside’. Exergonic reactions releases work energy. Exergonic reactions are different from exothermic reactions, the one that releases only heat energy during the course of the reaction. So, exothermic reaction is one type of exergonic reaction. Exergonic reaction releases work energy in different forms like heat, light or sound. For example, a glow stick releases light making that an exergonic reaction and not an exothermic reaction since no heat is released. Even endothermic reactions at very high temperature are exergonic.
Please provide complete step by step answer:
A customer orders 200ml of Sumatran coffee at precisely 60.0°C. You then need to drop the temperature of the coffee, initially at 90.0°C, to the ordered temperature.
In order to simplify the calculations, you will start by assuming that coffee has the specific heat and density as if water. In the following parts, you will remove these simplifications. Solve now this problem assuming the density is 1.000 g/ml for coffee and its specific heat capacity is 4.184 J/(g ºC).
If you had used ice cubes to cool the coffee, your calculation of q would have been a two- step process: (1) the ice at 0 oC first has to melt (energy added to go from solid to liquid; and then (2) to warm the liquid from 0 oC to the final temperature where
q = mice cice + mwater cwater ∆T where cice = 2.11 J/ g . oC
cwater = 4.184 J/ g . oC
(Note: there is no ∆T for the first step since melting of the ice occurs at 0 oC, no temperature change)
What mass of ice would you need to use to achieve the same result (qice = qmilk)? (Note: mice = mwater)
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