When Frankenstein dissolves the severed arm with acid, the arm as first shown at the beginning of the scene is significantly different in appearance than the one which is shown actually being dissolved.
When Polidori introduces Victor to the creature in his carriage, the interior point of view shot shows a Chinese servant closing the carriage door. A split second later, in a reverse angle shot from the exterior, the servant has vanished.
When Victor is talking to Elizabeth outside the church at his brother's funeral, he is holding his right hand on her shoulder. The shot switches to Elizabeth's face, and his hand is still on her shoulder. In the next wide shot, Victor's hand is down by his side. The following closeup of Elizabeth shows Victor's hand back on her shoulder.