Um... that will FURTHER acidify the soil.
To fix acid soil, you have to add a base or buffer that functions as a base in that reaction.

Get a pH test kit to verify your soil is acid.
Get the pH up/down that is meant for plants NOT POOLS.
Add a very small amount of pH up to bring a gallon of water to a slightly HIGHER pH than you want- like, 7.2.
Water with this until the pH of the runoff out the bottom of the pot reads 6.8.
There's a sticky about this at the top of the section.