Change of resolution of an image with Gimp does not show in file system and in chrome

Change of resolution of an image with Gimp does not show in file system
and in chrome

I have two questions.
When I open and save a png image in Gimp, the size in the file system
changes. I use the default settings.
When I change the resolution of a png image and save it, the size in the
file system equals the size mentioned in my first question (where I did
not change the resolution, but only saved). In Gimp the width and height
are changed, but in my browser, Chrome, not.
Thanks,
Eric J.