PLEASDE PLE A SHELP What is the change in enthalpy of the first reaction below, given the enthalpies of the other two reactions? 2C(s) +0,(8) 200(g)
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C(s) +0,(g) - CO2(g) AH°-394 kJ/mol
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CO(s) +0,() CO2(g) AH° = -283 kJ/mol

a is the correct answer

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