Yes. Click on the "Sent Mail" tab which will allow you to view four important aspects of sending emails: who you have sent emails to, who received them successfully, those that were undeliverable and those that are still pending.
Tip: This is a great tool when combined with the reports tool! You can compare those who have donated to your page to those who you have emailed. Therefore, you can send a second request to someone who has not already donated and this will prevent you from sending duplicate requests.