J.R. S. answered 10/06/20
Ph.D. in Biochemistry with an emphasis in Neurochemistry/Neuropharm
Please see previous questions and answers and do this one the same way.
q = mC∆T
q = 0.606 J
m = 261 mg = 0.261 g
C = ?
∆T = 19.5 - 2.8 = 16.7º
Solve for C and get your answer in J/gº (use 2 sig.figs. based on 2.8ºC)