Using Quotation mark " or not

[hugomosh]

I feel like a noob here but I am wondering what is that I am missing:

If I run:

export GIT_REPOS_ROOT="~/repositorios_git/"
    mkdir ${GIT_REPOS_ROOT}
    chmod 711 ${GIT_REPOS_ROOT}

I get chmomkdir: cannot create directory~/repositorios_git/': No such file or directory`

But if i change it to:

export GIT_REPOS_ROOT=~/private_repos/
mkdir ${GIT_REPOS_ROOT}
chmod 711 ${GIT_REPOS_ROOT}

It works fine.

Are we suppose to take the quotation marks or is it that I am using a differnt bash?
Je n comprendo pa.

Thank you for the help : ]