Consider the reaction 2A + 3B ---> 3C + 2D. The standard enthalpy of formation for A, B, C and D are -79.8, 49.2, -145.8, and -87.4, respectively in kJ / mol. What is the standard enthalpy change for the reaction in kJ/mol?

personal, she chose to do it.

i wish i could but this one is weird give me abc and i can solve it.

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