The progress of a reaction in the aqueous phase was monitored by the absorbance of a reactant at various times: Time/s 0 54 171 390 720 1010 1190 Absorbance 1.67 1.51 1.24 0.847 0.478 0.301 0.216 Determine the order of the reaction and the rate constant.

percent abundance for cu-63 can be shown as:

63 x + 65 (1-x) = 62.9296

65 - 62.9296 = 2 x

x = 1.035

thus, percent abundance for cu-63 is 1.035

percent abundance for cu-65 can be shown as:

63 x + 65 (1-x) = 64.9278

65 - 64.9278 = 2 x

x = 0.0361

thus, percent abundance for cu-63 is 0.0361

the mass spectrum of cu-63 showing the intense peak as, this isotope is found in nature more abundantly around 92.38 % in comparison to cu-65 which is found 62.58 % naturally