total mass of mixture = 337+16 = 353 g
initial temperature = 23 c
final temperature = 28.7 c
DT = 28.7 -23 = 5.7
heat released in the process (q) = m*s*DT
                                                          Â
= 353*4.184*5.7
                                                           Â
= 8.42 joule
no of mole of solid = 16/80.4 = 0.2 mole
DHsol = q/n  = 8.42/0.2 = 42.1
kj/mol
