Can I use lime survey to send my 10 questions to 5000 selected emails ? THANKS

Short answer : yes (i do for more than 100 000 email, with LimeSurvey CE and my own SMTP)

Yes, this is possible. Denis Chenu made a customized setup for this, but even out-of-the box LS will be able to send out 5000 invitations. But it will take some time, because it will be done in batches of 50 per block.

So you will send out 100 blocks of 50 emails. In the most recent versions of LS this will be triggered automatically, so you can just start and the installation will send out 50 mails per time slot, which is 1 minute, as far as I know.

I didn't speak of my plugins, in fact : my sendMailAjax plugin was done just after sending 100 000 emails (when we don't have an automatic click next .