Answer:
Cu(s) in Cu(NO₃)₂(aq)
Explanation:
The standard reduction potential (E°) is the energy necessary to reduce the atom in a redox reaction. When an atom reduces it gains electrons from other than oxides. As higher is E°, easily it will reduce. The substance that reduces is at the cathode of a cell, where the electrons go to, and the other that oxides are at the anode of the cell.
The standard reduction potentials from Al(s) and Cu(s) are, respectively, -1.66V and +0.15V, so the half-cell of Cu(s) in Cu(NO₃)₂(aq) is the cathode.
The negative side of another magnet
Explanation:
The emission of a beta particle is the result of the rearrangement of the unstable nucleus of the radioactive atom in order to acquire stability. For that, a phenomenon occurs in the nucleus, in which a neutron decomposes giving rise to three new particles: a proton, an electron (β particle), and a neutrino. The antineutrino and electron are emitted. The proton, however, remains in the nucleus.
The symbol is used to represent beta particles.
Answer: b. Beta