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What is the enthalpy change of dissolving 10 grams of sodium chloride (NaCl) in 100 ml of water, given that the final temperature of the solution is 25°C and the initial temperature of the water was 20°C?

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To calculate the enthalpy change of dissolving sodium chloride in water, we can use the formula:q = mcTwhere q is the heat absorbed or released, m is the mass of the solution, c is the specific heat capacity of the solution, and T is the change in temperature.First, we need to determine the mass of the solution. Since the density of water is approximately 1 g/mL, the mass of 100 mL of water is 100 grams. Adding the 10 grams of NaCl, the total mass of the solution is 110 grams.The specific heat capacity of water is 4.18 J/gC. Assuming the specific heat capacity of the NaCl solution is similar to that of water, we can use the same value for c.The change in temperature  T  is the final temperature minus the initial temperature: 25C - 20C = 5C.Now we can plug these values into the formula:q =  110 g  4.18 J/gC  5C  = 2299 JSince the temperature of the solution increased, the dissolution of NaCl is an endothermic process, meaning it absorbed heat from the surroundings. Therefore, the enthalpy change of dissolving 10 grams of sodium chloride in 100 mL of water is +2299 J.

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