1. The problem statement, all variables and given/known data The radial distribution factor for a 1s orbital given: R10 Calculate the expected value for potential energy of a He atom in the ground state. 2. Relevant equations i understand the integral math where I solve down to <1/r> = z/a but now, how do i use the V(r) = Z/(4(pi)E) = k (1/r) equation 3. The attempt at a solution i know Z is 2 for He and E is in coulombs and I need to end with joules, but I am just stumped on this part.