The answer by annav is correct that the neutron decay products will travel in straight paths in a vacuum chamber; the electron and proton will interact with the walls of the chamber, slow down, and become ordinary matter. (Most actual neutron traps involve strong magnetic fields, which make the charged particles travel on non-straight paths, but that seems like a minor detail.)
However: because the neutron decay involves three objects, the distribution of energy and momentum among the electron, proton, and neutrino is random. The total energy released in the decay is roughly 750,000 eV, which is typically shared more-or-less equally between the electron and the neutrino. However, if the neutrino carries away so much of the energy that the electron and proton together have less that 13 eV, the binding energy of the hydrogen atom, then it is possible for the electron to be immediately captured. This is called "bound beta decay", $\rm n \to H+\bar\nu_e$. As of 2014 this process has not been observed.