Citric Acid is often used in cosmetic formulations to alter an alkaline pH. Combine with baking soda and you can easily create your own bath bombs and fizzing bath salts. To ensure longest shelf life, store in cool, dry airtight container. Humidity and moisture are difficult to avoid, so we recommend using your citric acid within 6 months for optimum results. Fine grain salt (similar to table salt) and soluble in water. All natural