1.) Write a partial decay series for At-217 undergoing the following sequential decays: α, β, α, β. 2.) The hydride of an unstable nuclide of a Group IIA metal, MH2(s), decays by a-emission. A 0.025-mol sample of the hydride is placed in an evacuated 1.8 −L container at 298 K. After 88 minutes, the pressure in the container is 0.44 atm. Find the half-life of the nuclide.