Which chemical symbol represents hydrogen?

The chemical symbol for hydrogen is represented by a single letter, "H." This symbol is derived from the first letter of the name of the element, which is a common practice in chemistry for denoting elements. Each element has a unique one- or two-letter symbol, and hydrogen, being the first element on the periodic table, is symbolized simply as "H."

Other choices present different elements: "He" stands for helium, "Hy" is not a standard designation for any known element, and "Hg" represents mercury. Understanding the periodic table and the specific symbols assigned to each element is crucial in chemistry. The simplicity of hydrogen's symbol highlights its fundamental nature in the field of science, as it is the most abundant element in the universe and plays a crucial role in various chemical reactions, including those vital to life.