Question

Answer the following questions on a black paper, take a picture and email it back to me as PDF. Must show all the steps and calculations. (Use S.I. units for all the parameters) If a hot (200 °C) 50g aluminum (Sai = 900 JKg-1K-1) block is immediately immersed into 200ml water inside an ideal copper calorimeter (Scu= 386 JKg-1K-1), (a) what will be the final temperature of the mixture? Note that, the mass of the calorimeter is 200g and it was in equilibrium with the water in room temperature (25°C) before the mixture. (Swater = 4200 JKg 1K-1) (b) What will be the final temperature of the mixture if an ice block (Sice=2100 JKg 1K-1) of mass 20g and temperature -10°C is also immersed into the water?

Answer 1

50 g = mass of Aluminium = Spuitto heat of Aluminium 900 J kg'K Initial temperature of Aluminium Ti = 200°c 200 g mass of Calorümeter = Spuific heat of Copper Calorimehera Initial temperature of Calorimeter Tci 386 5 Kg K 25°C = = 200g volume of water 200 ml mais of water 200X1 Spuific heat of water 4200 J kg'K' Initial temperature of water Tei = Twi =25°c Let the final Temperature of mixture T = Tf

Now of ie Amur applying principal of conservatory energy Heat lost by Aluminium Heat gained by (Water t calorimeter) = ie 200 x goo (200-TF) = (2ook 86 X(T-25) † 200X 4200XC Tf-25) 900 (200-TF) = (386 +4200) Tf [(386*25) + (4200X25) 180000 - Goo Ts 4586 Tf 114650 5486 TS - 294650 294650 Tf 5486 Tf - 64.25° C

(6) 209 heat of Tomponatur of mixtun 64.25°C mass of ice Specific ice - 2100 J Kglk Initial tempuratwu of ice 20 -10°C Latent heal of fusion of ice 334 J/9 La thc final temperature of final mixture TS then Heat gained by ice Heat lost by mixture 20 X 2100X10 + 20 X334 + 20 X 9200 (74-0) 200 x 900 (14'- 64.25) # pou x 386 x 115'-64.25) Ce pou X 9200 (TF' - 64.25) 420000 + 6680 + 840 Dots' = - 180000ts - 77200 Ts' 840000 Ts' + [ 64.25 (180000 + 7 7200+840000)] (84000 + 180000 + 77200 + 840000) It! 64.25 X 109.7200) 426680] » [(64.2 1181200 TS Ts' Jout 70068 420 700 68420 59.32 ( 1181200

Therefore final temperature of the mixture is 59.32°C