If you have four cores and really want so that Chrome can only use one of them at a time you can just start it with taskset -c 0 google-chrome or maybe bett

If you have four cores and really want so that Chrome can only use one of them at a time you can just start it with taskset -c 0 google-chrome or maybe better taskset -c 0-2 google-chrome which will allocate cores 0-2 to Chrome, dedicating one core for your other work.