Question

DUNLICIS Here is a set of data for you to do the lab calcs with. Assignments The pre-lab video assignment gives more background information on what reaction is occuring, Grades You should solve for the heat of neutralization from the acid and base reacting. Syllabus solnmsoln X 4.184 J/gCx (TT:) = Joules tudent Evaluations Divide in Joules by 1000 to get ku Confer Zoom Divide kJ by the number of moles to find delta H in kJ/mol for the reaction STUDENT DATA Mass Calorimeter (8) Mass Calorimeter + HCI (8) Mass Calorimeter + NaOH (8) Mass Calorimeter + NaOH + HCI (8) Initial Temp, T. (OC) Final Temp T (OC) TRIAL 1 23.0432 54.0041 43.1590 74.1200 21.9 26.6 TRIAL 2 23.0432 53.4448 43.2944 73.6959 22.1 26.9 TRIAL 3 23.0432 54.7122 42.1463 73.8153 21.7 26.2

Answer 1

Here we do not have to convert the temperature in K since in the given formula the unit of temperature is given as 0C .

Mass of the soln. (NaOH + HU ) ) - Mass of Calorimeter + NaOH + HU - Mass of Calorimeter 8 Molecular mass of NaOH = 39.997 g/mol М» (eum мам и на 2 36 - 46 | мок . Molecular mass of the solm. (NaOH +HU (G)) a = 39.997 g/mol + 36.46 g/mol - = 76.457 g/mol For trial I Mass of the solution = 74 1200 g -23.043 20 = 51:0768 Number of moles of the solm. = Mass of the soln. Molecular mass of the soln. = 51.0768 g 76.457 g/mol 0:6680 mol z

qsohn = Mson *4.184 I/gc x (Tf - Ti). = 51.0768 g x 4.18 4 J/ge. (ox (26.6°C -21.9°C) = 1004.41 ] = 1004.41 kJ = 1.004 kJ 1000 :DH = 1.0044 kJ 0.6680 mal = 1.50 kJ/mol For trial a Mass of the soln. = 73.6959 g - .23.04 3 2 g = 50.6527 g No. of moles of the solu. = 50.65 27 g 76.4.57 g/mol = 0.6625 mol Isoln = 50.65279 x 4.18 4 J/g C X (26.9°C - 22.1°c) =1017.26

or q soln = J = 1.0172 ki 1017.26 k 1000 DH 2 1.0172 kJ 0.6625 mol = 1.53 kJ/mol For trial 3 Mass of the solution = 73.81539 - 23.0439 = 50.77219 No. of moles of the solu. = 50.77219 76.457 glmal = 0.664 1. mal - Zsoln. = 50.7721 g x 4.184 Ilge x (26. 2°C -21-7°c) = 955.937 J = 955.937 kJ = 0.9559 kJ 1000 DH 20.9559 kJ = 1.44 kJ/mol 0.664 1 mol