Answer is: Zn + Cu2+ → Zn2+ + Cu.
In this chemical reaction, there is transfer of electrons from zinc (Zn) to copper (Cu). Zinc change oxidation number from 0 to +2 (lost electrons) and copper change oxidation number from +2 to 0 (gain electrons).
Oxidation half reaction: Zn⁰ → Zn²⁺ + 2e⁻.
Reduction half reaction: Cu²⁺ + 2e⁻ → Cu⁰.
In other chemical reactions, there is no change of oxidation number of elements.
Answer:
The science or act of measuring changes in state variables of a body for the purpose of deriving the heat transfer associated with changes of its state due, for example, to chemical reactions, physical changes, or phase transitions under specified constraints.
Explanation:
The reaction will be spontaneous if Gibb free energy is negative, according the following relation:
G = H - T*S
where G is Gibbs free energy, T is change of enthalpy , T is temperature and S is change of entropy
In the case of ammonia:
G = -93000 - 356*(-198) = -93000 + 70488 = -22512 j/mol
As G < 0 then the reaction is spontaneous.
The correct answer among the choices given is option C. Above the critical pressure, a substance is a supercritical fluid. This fluid is any substance at a temperature and pressure above the critical point here the phases of the liquid and the gas do not exist.
