Are sodium and potassium metals, nonmetals, or metalloids? Note: Really hard to find a good video for this topic! Question a7. See all questions in Metalloids. Impact of this question views around the world. We find arsenic in pesticides, herbicides, and insecticides, but the use of arsenic for these applications is decreasing due to the toxicity of the metal.
Its effectiveness as an insecticide has led arsenic to be used as a wood preservative. Antimony is a brittle, bluish-white metallic material that is a poor conductor of electricity see Figure 4.
Used with lead, antimony increases the hardness and strength of the mixture. This material plays an important role in the fabrication of electronic and semiconductor devices. About half of the antimony used industrially is employed in the production of batteries, bullets, and alloys. Skip to main content. The Periodic Table.
Search for:. Metalloids Learning Objectives Define metalloid. List common metalloids and give their uses. Allied solutions. Book a free class now. Metals and Non-Metals Exercise. Matter and its Composition 2.
Physical and Chemical Changes 3. Elements, Compounds and Mixtures 4. Atomic Structure 5. Language of Chemistry 6. Metals and Non-Metals 7. Exercise 2. Looking to do well in your science exam? Learn from an expert tutor. They are the elements located on the right side of the periodic table. Q: From left to right across each period row of the periodic table, each element has atoms with one more proton and one more electron than the element before it.
How might this be related to the properties of nonmetals? A: Because nonmetals are on the right side of the periodic table, they have more electrons in their outer energy level than elements on the left side or in the middle of the periodic table. The number of electrons in the outer energy level of an atom determines many of its properties. As their name suggests, nonmetals generally have properties that are very different from the properties of metals.
Properties of nonmetals include a relatively low boiling point, which explains why many of them are gases at room temperature. However, some nonmetals are solids at room temperature, including the three pictured above, and one nonmetal—bromine—is a liquid at room temperature. Other properties of nonmetals are illustrated and described in the Table below. Most nonmetals are poor conductors of heat.
In fact, they are such poor conductors of heat that they are often used for insulation. For example, the down filling in this sleeping bag is full of air, which consists primarily of the nonmetal gases oxygen and nitrogen.
These gases prevent body heat from escaping to the cold outside air. Solid nonmetals are generally dull and brittle like these pieces of iodine. Like other nonmetals, iodine lacks the luster of metals and will easily crack and crumble. Reactivity is how likely an element is to react chemically with other elements. Some nonmetals are extremely reactive, whereas others are completely nonreactive. What explains this variation in nonmetals? The answer is their number of valence electrons.
These are the electrons in the outer energy level of an atom that are involved in interactions with other atoms. Simple atomic models of these two elements are shown in the Figure below. A: Fluorine is more reactive than neon. Although neon has just one more electron than fluorine in its outer energy level, that one electron makes a huge difference. Fluorine needs one more electron to fill its outer energy level in order to have the most stable arrangement of electrons.
As a result, fluorine is highly reactive. In fact, reactions with fluorine are often explosive, as you can see in the URL below. Neon, on the other hand, already has a full outer energy level. It is already very stable and never reacts with other elements. It neither accepts nor gives up electrons. Like most other nonmetals, fluorine cannot conduct electricity, and its electrons explain this as well. An electric current is a flow of electrons.
Elements that readily give up electrons the metals can carry electric current because their electrons can flow freely. Elements that gain electrons instead of giving them up cannot carry electric current. They hold onto their electrons so they cannot flow. They are the second largest class of elements after metals. Examples of nonmetals include hydrogen, carbon, chlorine, and helium.
Nonmetals are also poor conductors of heat , and solid nonmetals are dull and brittle. It depends on the number of electrons in their outer energy level. This explains why they cannot conduct electricity, which is a flow of electrons.
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