Chrome can be quite a memory hog, this is especially felt on older systems with less RAM. If you bring up More Tools -> Task Manager, you might notice that GPU Process consumes a lot of memory and is usually at the top. What is this process and how to disable it?
Chrome tries to use GPU as much as possible as a hardware accelerator for video and graphics rendered on the webpage. This can be turned off, though you must be aware that it will be done on the slower CPU otherwise.
Go to Settings -> System and disable Use hardware acceleration when available option. You will need to restart Chrome for this to take effect. The GPU process should be gone after this change.
Tried with: Chrome 44.0.2403.155 (64-bit) and Ubuntu 14.04