My car sounds like popcorn popping or someone throwing pebbles against the windows

Have your wheel bearings checked, when a wheel bearing is going bad it hums louder as you accelerate, when you stop or slow down the sound stops. A bad bearing does that, it over heats due to it not having enough grease on the bearing and will hum as you drive and get louder as you accelerate.

Might have clogged catalytic converter.

My S40 T5 makes a whirring sound due to the turbo but.... I did have an issue with the right front hub bearing. Lots of road noise while driving and it got louder as I accelerated. $215 dollars for the part.

sounds like a throw outbearig

It very well could be a vac leak or a problem with the air filter box.
If you can make the sound happen sitting in park, have someone listen around the engine compartment with a section of heater hose while you operate the controls.

Check your drivers side front CV joints and make sure the dust covers aren't ripped or broken. You;ll also want to check to make sure part of your splash guard isn't rubbing against your tire.

to test make your turn nice and slow with no throttle, then make the same turn accelerating slightly, if you hear the knocking/popping noise louder when accelerating, then it is probably the CV axels. get a free inspection at mieneke:).

Timing Chain Has Jumped a Tooth

Could be something jumping around in the exhaust. Is your catalytic conv in that area?

Has an exhaust leak. Either a gasket or a cracked exhaust manifold. Take it to a muffler shop for diagnosis.