Final answer:
Non-metals are typically brittle, dull, and poor conductors, with varying states of matter. However, semimetals or metalloids like silicon and germanium share properties with both metals and non-metals, such as being semiconductors and having a metallic luster.
Step-by-step explanation:
Non-metals generally exhibit properties that are opposite to those of metals, such as being brittle, not shiny, and poor conductors of heat and electricity. However, some elements display characteristics that are intermediate between metals and non-metals; these are known as semimetals or metalloids. Examples of metalloids include silicon and germanium, which have metallic luster and are semiconductors of electricity, sharing some properties with both metals and non-metals. These elements are located along the zigzag line on the right side of the periodic table. While non-metals tend to be dull and are usually poor conductors, they can form various states of matter, such as gases like nitrogen, liquids like bromine, or solids like sulfur. Moreover, non-metal structures are highly variable, with greater electronegativity and electron affinity compared to metals, leading to the creation of molecular structures and acidic oxides.