Final answer:
In the nuclear reaction 40K → 2Ca+ce20, a is 40, b is 20, and c represents the charge of the emitted particle. It is a type of beta decay where a neutron is converted into a proton, and an electron is emitted.
Step-by-step explanation:
In the nuclear reaction 40K → 2Ca+ce20, the letters a, b, and c represent the atomic numbers of the atoms involved. In this case, a is 40 (representing the atomic number of potassium), b is 20 (representing the atomic number of calcium), and c is the charge of the emitted particle.
Since the reaction involves the emission of a particle, it is a type of beta decay. Beta decay occurs when a neutron in the nucleus is converted into a proton and an electron is emitted. This process helps to stabilize the nucleus and bring it closer to the region of stability.