Final answer:
The product of electron capture by Fe-55 is Mn-55.
Step-by-step explanation:
The product of electron capture by Fe-55 is Mn-55.
In electron capture, an electron from the inner electron shell is captured by a proton in the nucleus, resulting in the conversion of a proton to a neutron. This causes the atomic number to decrease by one, while the mass number remains the same.
In the case of Fe-55, the electron capture process results in the formation of Mn-55.