If you want to block any  site in Chrome, then you need to install a Chrome extension .  The name of the extension is Personal Blocklist.

This personal blocklist extension will transmit to Google the patterns that you choose to block. When you choose to block or unblock a pattern, the extension will also transmit to Google the URL of the web page on which the blocked or unblocked search results are displayed.

Also Read- How To Block Websites In Mozilla Firefox