Influence on the electrolyte resistance of the contact angle of a bubble attached to a disk electrode

•We calculate the ER increment due to bubble of any contact angle on disk electrode.•The ER increment is up to 40% of that of a perfect sphere near the electrode edge.•We developed a technique to measure the ER increment due to a truncated sphere.•Despite low values, the ER increments could be experimentally measured.•We obtained an excellent agreement between the theoretical and experimental results.