a student obtains the following data for his experimental runs for the unknown acid                      run 1 – 0.2541 m            run 2 – 0.2668 m            run 3 – 0.2549 m            run 4 – 0.2554 mthe unknown acid is correctly known to be 0.2542 m. is the % error for the student’s data? is the % spread for the student’s runs?

The % error in the student’s data is  
Correct score - run score/ correct score * 100
 In run 1 we have
  0.2542 - 0.2541/0.2542 * 100 = 0.000393391031 = 0.03933%
 In run 2 we have 
 0.2542 - 0.2668/0.2542 * 100 = -0.00495672699 = -0.495%
 In run 3 we have
 0.2542 - 0.2549/0.2542 * 100 = -0.00275373721 = -0.275%
 And run 4 we have
 0.2542 - 0.2554/0.2542 * 100 = 0.00495672699 = 0.495
 
 The spread are 0.2542 - 0.2541 = 0.0001 and 0.2542 - 0.2668 = -0.0126
 Also 0.2542 - 0.2549 = -0.0007 and 0.2542 - 0.2554 = -0.0012

Exothermic,  physical change after it is already baked