nonmetal

{| style="float:right; margin-left:2.5em; margin-bottom:1.2em; font-size:95%; max-width: 450px; border:1px solid grey" | style=text-align:center|A periodic table extract |- | 450px| alt=A grid with 7 rows labeled periods "1" to "7" and 10 columns labeled as groups "1", "2", "3–11", and "12" to "18". ¶ Most cells represent one chemical element and are labeled with its 1 or 2 letter symbol in a large font above its name. Cells in column 3 (labeled "3–11") represent a series of elements and are labeled with the first and last element's symbol. ¶ Row 1 has cells in the first and last columns, with an empty gap between. Rows 2–3 have 8 cells, with a gap between the first 2 and last 6 columns. Rows 4–7 have cells in all 10 columns. ¶ A bold falling staircase line separates the rightmost 6/5/4/3/2/1 cells in rows 2–7. ¶ 17 cells above and right of the staircase are tan-colored: both cells row 1 and all cells to its right except the first one. ¶ 9 cells along the staircase are specially colored: gray in rows 2–5 and brown in rows 6-7: the first cell after it in rows 2–7 and first cell before in rows 4/5/7. ¶ The rest of the cells have light gray letters on a white background. |- | |- | style="padding-left:5px; font-size:95%;"|always/usually considered nonmetals |- | style="padding-left:5px; font-size:95%;"|metalloids, sometimes considered nonmetals |- | style="padding-left:5px; font-size:95%;"|status as nonmetal or metal unconfirmed |- |}

In the context of the periodic table, a nonmetal is a chemical element that mostly lacks distinctive metallic properties. They range from colorless gases like hydrogen to shiny crystals like iodine. Physically, they are usually lighter (less dense) than elements that form metals and are often poor conductors of heat and electricity. Chemically, nonmetals have relatively high electronegativity or usually attract electrons in a chemical bond with another element, and their oxides tend to be acidic.