The accepted ΔH for a reaction is - 42.3 kJ/mol. A student has performed a lab experiment to determine the enthalpy change of the same reaction. Calculate the percent error

Student 1 Exp. ΔH (kJ/mol)

Trial 1 - 43.8

Trial 2 - 41.0

Trial 3 - 42.7

trial 1: % error = 3.546 %

trial 2: % error = 3.073 %

trial 3: % error = 0.946 %

Explanation:

% error = ((ΔHi - ΔH) / ΔH) * 100

∴ ΔH = - 42.3 KJ/mol

trial 1:

∴ ΔH1 = - 43.8 KJ/mol

⇒ % error = ((-43.8 - (-42.3)) / (-42.3)) * 100

⇒ % error = (0.03546) * 100 = 3.546 %

trial 2:

∴ ΔH2 = - 41.0 KJ/mol

⇒ % error = ((-42.3 - (-41.0)) / (-42.3)) * 100

⇒ % error = (0.03073) * 100 = 3.073%

trial 3:

∴ ΔH3 = - 42.7 KJ/mol

⇒ % error = ((-42.7 - (-42.3)) / (-42.3)) * 100

⇒ % error = (9.456 E-3) * 100 = 0.946 %