Homework Answers
a) It is an exothermic process: the temperature increases due to a heat transfer from the system.
b) The temperature change is measured from the starting temperature (26°C) to the constant maxiumum value (~34°C) so:
c) The enthalpy of solution can be obtained as:
where m is the mass of water (remember that density of water is 1g/mL so, the volume and the mass are numerically identical) and Cp is the heat capacity of water (4.184J/g*°C), so:
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The molar mass of solid is 110.98 g/mol PART IV MOLAR MASS OF SOLID Mass of...
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The molar mass of solid is 110.98 g/mol
PART IV MOLAR MASS OF SOLID Mass of Calorimeter (g) 10%1841 991565p S10005 Mass of Calorimeter plus water (g) Mass of water (g) Mass of unknown solid (g) alig'c 28.3 Initial temperature (°C) Final temperature (C) Temperature change (AT) Heat, q (kJ) Heat of solution per gram of solid (kJ/g) Heat of solution per mole of compound (kJ/mol) DATA ANALYSIS 1. Calculate q solution (Cs for water is 4.184 J/g°C) 2. Identify...
8 4 points When a 0.456 g sample of salt is dissolved into water in a completely insulated calorimeter (a simple styrofoam coffee cupl. the temperature of the 500 ml water decreases by 0.940°C. What is the heat for the system (the salt dissolving)? O 1.79kJ 0 +1.80 kJ O +214) O 0.214 - 1.96 kJ +1.97 Ooo
A generic solid, X, has a molar mass of 72.6 g/mol. In a constant-pressure calorimeter, 16.6 g of X is dissolved in 365 g of water at 23.00 °C. X($) — X(aq) The temperature of the resulting solution rises to 27.80 °C. Assume the solution has the same specific heat as water, 4.184 J/(g°C), and that there is negligible heat loss to the surroundings. How much heat was absorbed by the solution? 9 kJ What is the enthalpy of the...
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