Hope this is not a too late answer.
To activate SWAP, you will need to open terminal (Ctrl + Alt + t). In terminal, type the following command:
swap enable 2000
This will create a 2GB SWAP partition on your Chromebook’s SSD, adjusting the number will change the SWAP size. The Chrome team recommends 2GB. A restart is required to activate your newly created SWAP partition. It is regarding as an experimental feature, and is not recommended for daily use. To disable the SWAP partition type the following command in terminal and restart:
Hopefully this feature will prevent your Chrome tabs from crashing and you should be able to use more tabs. A handy feature until we get Chromebooks with more RAM.