Question

Calculate the enthalpy change when 50 mL of 0.2 M sodium chloride solution is mixed with 50 mL of 0.2 M silver nitrate solution. The final temperature of the solution was found to be 25°C and the initial temperature of the reactants was 30°C. The specific heat of the solution is 4.18 J/g°C, and the density of the solution is 1.00 g/mL.

Answer 1

To calculate the enthalpy change, we need to first determine the heat released or absorbed during the reaction. We can do this using the formula:q = mcTwhere q is the heat released or absorbed, m is the mass of the solution, c is the specific heat of the solution, and T is the change in temperature.First, let's find the mass of the solution. Since the density of the solution is 1.00 g/mL, and we have a total volume of 100 mL  50 mL of sodium chloride solution + 50 mL of silver nitrate solution , the mass of the solution is:m = 1.00 g/mL * 100 mL = 100 gNow, let's find the change in temperature. The final temperature is 25C, and the initial temperature is 30C, so:T = 25C - 30C = -5CNow we can calculate the heat released or absorbed:q = mcT =  100 g  4.18 J/gC  -5C  = -2090 JSince the heat is negative, this means that the reaction is exothermic and heat is released. The enthalpy change is equal to the heat released or absorbed, so:H = -2090 JThe enthalpy change when 50 mL of 0.2 M sodium chloride solution is mixed with 50 mL of 0.2 M silver nitrate solution is -2090 J.