How does the setblock command work in 1.13?

I am trying to make a setblock command destroy a chest with air, making it drop the items. This worked perfectly in 1.12 but now in 1.13 I can't get it to work in a command block, and even when I get it to break a chest using my command prompt in chat, it doesn't drop the items. How does this new system work and how can I get it to work if it is even possible?