Question

Question 6 (0.5 marks) Two solids, 4.20 g of sodium hydroxide and 5.00 g potassium hydroxide are added to 200.0 mL of water in a calorimeter. If the initial temperature of the water is 20.0 °C, Asolution H (NaOH) = -44.3 kJ/mol, and solution (KOH) = -56.0 kJ/mol, calculate the final temperature of the solution. You may need to obtain some data from your textbook when answering this question. Assume the specific heat capacity of the solution is the same as the specific heat capacity of water.

Answer 1

Moleculan weight d NaoH = 40 a/mo KOH56 g/mol 4.20 3 '. Moles d NaoH taken 0.105 mol 40 mel 5.00 0.0893 mol КОН 56 amol indi cates heat is The negative sign betone 4olution nelesed wil not be used dissolution So tis sign during the magnihtude d melesed heat. to cal culate k J -x 0.0893 kJ x 0.105 mo 56.0 Noo, total heat elecsed = 44,3 mo mo 9.6523 kJ 9652.3 J (: IkJ = 1000 J) Nov, mass f the solution = 200.0 mLX J a/mL + 4.20 at 5.00 ( g/mL) = 209.2 So, ir the tinal temperatune in T'e tren mass xspectic heat x temp. change solution Heat absonbed by = 209.2 gx 4.184 Jg'x (T-20) X 9652.3 J (ANSER) T31.03 °C