There is no option in the preferences of Google Chrome to enter a proxy server, but it is possible to specify one using command line arguments. You have to execute the Google Chrome binary inside the application bundle from terminal. First open terminal and then cd to your applications directory or wherever Chrome is stored.
cd /Applications
Next start chrome with the proxy server option:
Google\ Chrome.app/Contents/MacOS/Google\ Chrome --proxy-server="socks5://host:port"
Replacing host and port with your information. Keep in mind that although HTTP requests are being serviced through the proxy DNS lookups are not going through the proxy server. You can add "&" to the end of the command to have it execute in the background.
