Question

unemical Changes / Module 4 Lesson 1 Assignment estion 18 Use the following information to answer the next 3 questions ot yet swered larked out of .00 Pflag question Naphthalene (C10H(s) originally was used as the main ingredient in mothballs. Its use was discontinued because of health concerns exposure to large amounts of naphthalene may damage or destroy red blood cells, cause confusion, nausea, vomiting, diarrhea and jaundice. Naphthalene dust can be an explosion hazard when exposed to heat or flame. It may ignite by friction, heat, sparks or flame. May re-ignite after the fire is extinguished and containers of naphthalene may explode when heated. The following calorimetry experiment was designed to determine the enthalpy of combustion of naphthalene, Thermometer Aluminium cover Water Alunnium calorimeter hexamine tablet Fo.1 A 1,00 g sample of naphthalene is burned in a 25.00 g aluminium calorimeter that contains 250.0 g of water. The temperature of the calorimeter and the water increases by 35.50 °C. According to this data, the molar enthalpy of combustion of naphthalene is MJ/mol Hint Includes both the water and the aluminum calorimeter in your calculation. Note that the units for your answer should be in Mi/mol Record your answer to 3 significant digits. Include sign; do not include units.

Hello can someone help me with this question? I spent so much time on it but it seems I am kind of stuck for some reason and my teacher can't answer my emails due to spring break. Thank you.

Answer 1

Specifte heat capacity of alluminum = 0.9211 Jlge, specific heat of water = 4,1841/g*c, Total heat energy evolved = 125,00gx.0.9211J/ge * 35.50°C ? +250.09 * 4.184J/q°C¥35,50°C 418 35,50°C = 817,48 + 37133,0v = 37950,481 Molar mass of naphthalene = 128,1705 g/mol 37950480 x 128:17059. Ig of naphthalene produces 39950,48J. 12811905g » lg 3 4.864 X1060 So, the molar enthalby of combustion i .. = -4.864 MJ/mot,