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linhy
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Homework Statement
a 25 kg block of ice is heated from -10 celcius to 78 celcius. HOw much heat is required.
The amount of heat required to boil water depends on several factors, such as the initial temperature of the water, the atmospheric pressure, and the altitude. On average, it takes about 1 calorie of heat to raise the temperature of 1 gram of water by 1 degree Celsius. So, to boil 1 liter of water (1000 grams) from room temperature (25 degrees Celsius), it would require 75,000 calories of heat.
The amount of heat required to melt a substance, also known as its heat of fusion, varies depending on the substance. Each substance has a specific heat of fusion, which is the amount of heat required to melt 1 gram of the substance. For example, the heat of fusion for water is 334 joules per gram, so it would take 334 joules of heat to melt 1 gram of ice into 1 gram of water.
The amount of heat required to raise the temperature of a substance depends on its specific heat capacity. Specific heat capacity is the amount of heat required to raise the temperature of 1 gram of a substance by 1 degree Celsius. For example, the specific heat capacity of water is 4.184 joules/gram °C, so it would take 4.184 joules of heat to raise the temperature of 1 gram of water by 1 degree Celsius.
The amount of heat required for a chemical reaction, also known as the heat of reaction, is determined by measuring the change in enthalpy of the reaction. Enthalpy is a measure of the total energy of a system, and the change in enthalpy is the difference between the energy of the reactants and the products. This change in enthalpy can be measured using a calorimeter.
The amount of heat required for a process can be calculated using the formula Q = mcΔT, where Q is the heat required, m is the mass of the substance, c is the specific heat capacity, and ΔT is the change in temperature. This formula can be used for various processes, such as melting, boiling, and raising the temperature of a substance.