When you send a friend request to someone on Facebook, they can either approve your friendship request, decline it or leave the request untouched.
Now Facebook will inform you when friends approve your request but there’s no easy way to figure out the names of people who are yet to approve your friendship requests.
So here’s a simple Facebook hack to help you retrieve this information:
1. Open your Facebook Privacy page by clicking the "privacy" link at the top right corner.
facebook privacy 
2. Click the link that says "Poke, Message, and Friend Request"
3. The next screen will show you a list of Facebook members who are not your friends but can see some parts of your Facebook profile. They are in the list because you have contacted them in the past through a poke or friend request though you are not mutual friends.
And this is the list that has all the names who have not confirmed your friendship request yet. Unfortunately, there is no way to cancel a friend request once it has been made so you cannot delete names from the list on your own.