|It looks like you cloned the disk exactly. Most cloning programs also have an option to expand the drive to fill the available space.|
You have two options:
1. Use Disk Management to create a new partition using the currently unused space.
2. Use a partition resizing program (GParted is free and does the job) to expand your current partition to fill the whole disk.
(If any of these terms are unfamilar to you just Google them.)