Question

AutoSave OFF Aos 50 CHEM101L-Lab Report 6 - Calorimetry - Saved to my Macy Home Layout Tell me Share Comments Insert Draw Design Layout References Mailings Review View Cambria 12 AA Aa A E EVEU BI U ab x, x A LA EEEE E Table Design ALT D AaBbCcDdEe AaBbCcDdee AaBbCcDc AaBbCcDdEt AaBb No Spacing Heading 1 Heading 2 Title Paste Normal Styles Pane Dictate Heat of solution of a salt Salt name: Potassium Iodide (KI) Trial 1 75.00 ml Trial 2 75.00 ml 22 °C 22 °C 5.00 g 5.00 g 18°C 17°C Volume of water used, mL Initial temperature of water (T1) in °C Mass of salt taken in g. Moles of salt taken Final temperature (T2) in °C AT (T2-T1) in °C Total mass of solution (salt + water) in g. Heat flow Q (in J.) Heat of Solution AH (KJ/mol) Mean value of AH Mean value of AH (average of both values of AH) Is the solution process of this salt (the salt dissolving in water) an endothermic or an exothermic process? Explain. Page 2 of 3 455 words English (United States) Focus E 6 - - • - + 146%

Answer 1

Mean value of AH = AH, +4Hz 2. = 0°0418 + 0'0523 KJ/mol 2 z 0°0470 kJ/mol Since the solution proun of this salt a heat is absorbed (ie temperature of soll decreares) hence reaction is endothermic and AH is positive.

We know, Heat flow (6) May of water x (Change in tempo X Hent capacity of water since Heat capacity of water. 4.184 I Ige ... Heat flow (a) = (0759 ) x (-40) X(4-1843/g °c) - 1.255 I In Trial 2 Heat floa (Q.) = ('075g) x (52)x(4+1849/98) - 1.569 J Since Heat of solution - heat flow N Moler In Treial 1 Heat of solution (AH,) = -/- 1.255) 030 z 41188 g/mol = 0°0418 15]/mol In theial 2 K 1'569 ) Head of solution (Alle) = -( 030) = 5213 g/mol z 0°0523 kJ/mol