Answer:
-12.5 kJ/mol
Explanation:
The free-energy predicts if a reaction is spontaneous or not. If it is, ΔG < 0. When a reaction happens by steps, the free-energy of the global reaction can be calculated by the sum of the free-energy of the steps (Hess law). If it's needed to operations at the reaction the same operation must be done in the value of ΔG (if the reaction is inverted, the signal of ΔG must be inverted).
Phosphocreatine → creatine + Pi ∆G'° = –43.0 kJ/mol
ATP → ADP + Pi ∆G'° = –30.5 kJ/mol (x-1)
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Phosphocreatine → creatine + Pi ∆G'° = –43.0 kJ/mol
Pi + ADP → ATP ∆G'° = 30.5 kJ/mol
The bold compounds are in opposite sides, so they'll be canceled in the sum of the reactions:
Phosphocreatine + ADP → creatine + ATP
∆G'° = -43.0 + 30.5
∆G'° = -12.5 kJ/mol
It affects the volume of air you can inhale.
The reaction between zinc and hydrochloric acid is Zn + HCl = H2 + ZnCl2. It is a single replacement reaction where zinc metal displaces the hydrogen to form hydrogen gas and zinc chloride, a salt. Zinc reacts quickly with the acid to form bubbles of hydrogen.