Question

Use all of the information to answer the following practice questions. These practice problems will be similar to your theory questions on the test.

Determination of Standard Enthalpy of Solution of NaOH in Water Mass of NaOH and bottle = 4.61 g Mass of bottle = 2.51 g Mass of NaOH = 2.10 g Mass of calorimeter and solution = 58.63 g Mass of calorimeter = 9.41 g Mass reaction mixture = 49.22 g Ti = 21.6°C Tg = 30.2°C AT = 8.6°C Using the information provided in the table above, answer the following questions: Q1 a) What is the value of q, where - Cwater = -4. 184? (Hint: q= -Cwater*msoln* AT) b) n = NaOH where Mr = 40.00, calculate the value of n in mol? Mr c) Hence, calculate AH° = q/n, in J and kJ?

Answer 1

delta Ho of a reaction is negative, hence the reaction is exothermic in nature.

given: mass of AlaOH 2.10g ssg veuetton mixture - 49.22 Ti 21.6 °C 1 = 30.2°C AT = 8.6 °C هے solution : w.K.T 9= -Custok mosogena AT cu specific heat capacity a water - 4.184 310.9 q = - 4.184 I Agf * 49.22g x 8.6 € q -1.79 x103 I 0 -1.77 KJ O nog moles, on of moles, n = mass molar mass of 5.25x100 moles moles NaOH 2.10g 40 gmot! © W.KiT oHº q ln AH -1.77 XI0²J 5.25x102 33.71x10 Joules AH = -33.71x10 Joules 67 -33.71 Killojoules