You are planning a birthday party for your niece and need to make at least 4 gallons of Kool-Aid, which you would like to cool down to 32 oF (0 °C) before the party begins. Unfortunately, your refrigerator is already so full of treats that you know there will be no room for the Kool-Aid. So, with a sudden flash of insight, you decide to start with 4 gallons (1 gallon = 3.7854 liters, and a liter (L) is 0.001 cubic meters) of the coldest tap water you can get, which you determine is 50 °F (10 °C), and then cool it down with a 1- quart (1/4 of a gallon) chunk of ice you already have in your freezer. The owner's manual for your refrigerator states that when the freezer setting is on high, the temperature is -20 °C. Will your plan work? You assume that the density of the Kool-Aid is about the same as the density of water. You look in your physics book and find that the density of water is 1.0 g/cm3 (1kg/L), the density of ice is 0.9 g/cm3 (0.9kg/L), the heat capacity of water is 4200 J / (kg °C), the heat capacity of ice is 2100 J / (kg °C), the heat of fusion of water is 3.4 x 105 J/kg, and its heat of vaporization is 2.3 x 106 J/kg.
Energy transfer
The flow of energy from one region to another region is referred to as energy transfer. Since energy is quantitative; it must be transferred to a body or a material to work or to heat the system.
Molar Specific Heat
Heat capacity is the amount of heat energy absorbed or released by a chemical substance per the change in temperature of that substance. The change in heat is also called enthalpy. The SI unit of heat capacity is Joules per Kelvin, which is (J K-1)
Thermal Properties of Matter
Thermal energy is described as one of the form of heat energy which flows from one body of higher temperature to the other with the lower temperature when these two bodies are placed in contact to each other. Heat is described as the form of energy which is transferred between the two systems or in between the systems and their surrounding by the virtue of difference in temperature. Calorimetry is that branch of science which helps in measuring the changes which are taking place in the heat energy of a given body.
You are planning a birthday party for your niece and need to make at least 4 gallons of Kool-Aid, which you would like to cool down to 32 oF (0 °C) before the party begins. Unfortunately, your refrigerator is already so full of treats that you know there will be no room for the Kool-Aid. So, with a sudden flash of insight, you decide to start with 4 gallons (1 gallon = 3.7854 liters, and a liter (L) is 0.001 cubic meters) of the coldest tap water you can get, which you determine is 50 °F (10 °C), and then cool it down with a 1- quart (1/4 of a gallon) chunk of ice you already have in your freezer. The owner's manual for your refrigerator states that when the freezer setting is on high, the temperature is -20 °C. Will your plan work? You assume that the density of the Kool-Aid is about the same as the density of water. You look in your physics book and find that the density of water is 1.0 g/cm3 (1kg/L), the density of ice is 0.9 g/cm3 (0.9kg/L), the heat capacity of water is 4200 J / (kg °C), the heat capacity of ice is 2100 J / (kg °C), the heat of fusion of water is 3.4 x 105 J/kg, and its heat of vaporization is 2.3 x 106 J/kg.
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