Your baking soda can work wonders and help you with your problems.
Learn the right procedures as demonstrated byNatural Health Remedieson YouTube.
This produces co2 which drowns the centipedes.

Image Credits: Natural Health Remedies via YouTube
You might have to do several rinses to kill your centipede problem.
This will also help to deter any future slimy invaders.
This dehydrates the ant and kills it.

Leave it overnight, then vacuum it up in the morning.
Note:If any step doesnt work then see if your baking soda is old.
If it still not working then give a shot to find out why or if the insects ate it.

*All these images are credited toNatural Health Remediesvia YouTube.