Even with eight tabs open for Chrome to use the amount of memory you're talking about there would have to be something else. Chrome has their own basic built in task manager to show how much it's using per page, and extension.
On a system with 2GB of ram I would still have free memory with tabs open, and running other applications. -- I distrust those people who know so well what god wants them to do because I notice it always coincides with their own desires- Susan B. Anthony Yesterday we obeyed kings, and bent our necks before emperors. But today we kneel only to the truth- Kahlil G.
I myself found that just leaving a Facebook page open for 24 hours, Chrome will eventually consume more than 3X the available physical RAM in the system. I have a laptop with 512MB RAM that I use in the kitchen for browsing. It becomes impossible to use after about an hour. After taking 8 minutes to launch Task Manager, I see that Chrome is using 1.7GB of memory! 512MB RAM, plus virtual memory overflow. The HDD LED never goes out--drive is swapping 24 hours a day. Shut down Chrome, load a page like DSLReports, and memory usage stays relatively flat at a couple hundred MB. Pages like Facebook are doing something nefarious with all that memory usage.
Sounds like chrome isn't reining in it's cache, or the plugins/extensions are not given any memory boundaries. That would have actually been an interesting internal task manager screenshot from chrome.
Similar story happens with visiting SHOUTcast Radio and listening some radio station there. Chromium (Iron) takes more and more memory until you have to close it... -- Keep it simple, it'll become complex by itself...