Baixe e instale a chave:
~$ wget -q -O - https://dl-ssl.google.com/linux/linux_signing_key.pub | sudo apt-key add -

Adicione o repositório da chave:
~$ sh -c 'echo "deb [arch=amd64] http://dl.google.com/linux/chrome/deb/ stable main" >> /etc/apt/sources.list.d/google-chrome-unstable.list'

Agora atualize os respositórios e instale o Google Chrome:
~$ apt-get update
~$ apt-get install google-chrome-unstable