Final answer:
A barium swallow, also known as a barium meal, is a diagnostic medical imaging procedure where a patient ingests barium sulfate, which enhances X-ray visibility of the gastrointestinal tract for the diagnosis of various conditions.
Step-by-step explanation:
A barium swallow is also called a barium meal or an upper gastrointestinal series. This medical imaging procedure involves the patient ingesting a suspension of barium sulfate, a chalky powder that is mixed with water to form a substance often referred to as a "barium milkshake." Due to the very low solubility of barium sulfate, represented by a solubility product constant (Ksp) of 2.3 × 10^-8, it remains largely undissolved as it coats the lining of the gastrointestinal tract. When a patient undergoes an X-ray after consuming this mixture, the barium makes it opaque to X-rays, thereby creating a detailed outline of the digestive organs. This procedure enhances the visibility of the digestive tract on the X-ray images, providing greater visual detail than conventional X-rays, which is critical for diagnosing conditions like acid reflux disease, Crohn's disease, and ulcers.