There are questions viewed thousands times in a relative short time. Is that because the view counting system consider also external users views? Therefore also views from people searching the net who are not member of the chemistry stack exchange communities are counted.
It's explained on Meta Stack Exchange here; basically, every visit to the page (by community members and people without an account) counts, but additional visits by the same browser within 15 minutes don't count.
Therefore also views from people searching the net who are not member of the chemistry stack exchange communities are counted.
That's correct. Actually, most of the traffic on Stack Exchange is 'anonymous'. You don't even know how much chemistry students you're helping with your questions and answers.
A view is a view. Whether it is a registered user or a guest; on a PC or on a smartphone; behind a VPN or not. They are accumulated.
Some questions seem to rank high on Google searches meaning lots of views trickle in at a faster rate than usual.
However, questions that reach thousands of views within a day were typically featured on the Hot Network Questions list which drives a lot of traffic from other SE sites to Chemistry.SE.