Q. Why Barium in a suitable form is administered to patients before an X-ray examination of the stomach? (UPSC Prelims 1999)
Answer: barium is a good absorber of X-rays and this helps the stomach to appear clearly in contrast with the other regions in the picture
Notes: Barium is given in adequate amount to patients before X-ray examination. The gut (gastrointestinal tract) does not show up very well on ordinary X-ray pictures. However, if you drink a white liquid that contains a chemical called barium sulphate, the outline of the upper parts of the gut (oesophagus, stomach and small intestines) shows up clearly on X-ray pictures. This is because X-rays do not pass through barium.