An acid is then added to create a thick gel.

The problem is if you add too much acid.

Finally, hydrofluoric acid is added to give the end product.

When neutralised (an acid is added) they produce a salt and water.

Be aware that when you add acid to the cooking water, as with juices, the rice takes longer to cook.

Retinoic acid may be added to your skin plan, or an antibiotic.

When one adds acid or base to a buffer the ratio of the two concentrations change.

To drive the reaction towards the product (ester), then add a bit more acid.

You need to add enough acid to keep the pH slightly acidic.

In your equation, we are adding nitric acid to this material.