authentication key given to respondents to access survey

I'm trying to administer a survey where I send students a randomized "key" that they must enter in order to access the survey. I want this key to be sent to them in the same email where they access the survey link. Is this possible? I'm aware of the authentication capabilities on the survey, but I'm not sure if/how to create a random code for them that is sent to them along with the survey itself.