Como acessar unidades externas do Linux Chrome OS
To access external storage devices from linux on Chrome OS, you can navigate to
the /mnt/chromeos/removable/ directory.
From here you should see your external devices.
You might also need to go into Settings>Advanced>Linux Development Enviroment (beta)>Manage USB Devices
and then enable the devices you want to share. Access these devices as shown above.
Stormy Skylark