Sodium (Na):The symbol Na represents sodium in the periodic table, derived from the Latin word "natrium," another name for sodium. Sodium is the primary positive ion, or cation, found in the fluid outside cells. Its chemical symbol is Na+. When sodium bonds with chloride (Cl), it forms table salt (NaCl). Excessive sodium intake, like that from fast food such as hamburgers and fries, is eliminated through urine. Diets high in sodium are believed to lead to health issues. Both insufficient and excessive sodium levels can disrupt cellular function, with severe cases being potentially deadly. The normal range for blood sodium levels is between 135 and 145 milliequivalents per liter (mEq/L), or in international units, 135 to 145 millimoles per liter (mmol/L).
