Chapter 12 Lesson 3 Part 1 ByDesign Science, 8th Grade What Are Metals? Chapter 12 Lesson 3 Part 1 ByDesign Science, 8th Grade

Metals Metal is an element that is a good conductor of electricity and heat.

Metals Metal is an element that is a good conductor of electricity and heat. Most of the elements on the periodic table are metals.

Metals Recall that most metals are hard, shiny solids with high melting points.

Metals Recall that most metals are hard, shiny solids with high melting points. One exception is mercury, which is a liquid at room temperature.

Metals Recall that most metals are hard, shiny solids with high melting points. One exception is mercury, which is a liquid at room temperature. Metallic elements are generally somewhat flexible and bendable.

Metals Recall that most metals are hard, shiny solids with high melting points. One exception is mercury, which is a liquid at room temperature. Metallic elements are generally somewhat flexible and bendable. They can be hammered into thin sheets or other shapes, a property known as malleability.

Metals Most metals can also be drawn into long, thin, flexible wires, which is a property known as ductility.

Metals The chemical properties of metals vary widely.

Metals The chemical properties of metals vary widely. Some metals, such as sodium and potassium, react with oxygen or water vapor so rapidly that they must be storied in ways that keep they away from the air.

Metals The chemical properties of metals vary widely. Some metals, such as sodium and potassium, react with oxygen or water vapor so rapidly that they must be storied in ways that keep they away from the air. Others, such as gold, react very slowly with oxygen or water vapor.

Metals The chemical properties of metals vary widely. Some metals, such as sodium and potassium, react with oxygen or water vapor so rapidly that they must be storied in ways that keep they away from the air. Others, such as gold, react very slowly with oxygen or water vapor. A gold object can remain bright and shiny for thousands of years.

Metals Between these extremes are metals such as iron and copper that gradually rust or tarnish.

Alkali Metals The elements in Group 1 of the periodic table are the alkali metals.

Alkali Metals The elements in Group 1 of the periodic table are the alkali metals. The atoms of the alkali metals have one electron in the highest orbital.

Alkali Metals The elements in Group 1 of the periodic table are the alkali metals. The atoms of the alkali metals have one electron in the highest orbital. That electron is easily removed in chemical reactions, which makes that alkali metals extremely reactive compared with other metallic elements.

Alkali Metals They are so reactive that they are never found in pure form in nature.

Alkali Metals They are so reactive that they are never found in pure form in nature. They must be stored in airtight containers or covered with a layer of oil to isolate them from oxygen and water vapor in the air.

Alkali Metals They are so reactive that they are never found in pure form in nature. They must be stored in airtight containers or covered with a layer of oil to isolate them from oxygen and water vapor in the air. Otherwise, the metals would react rapidly and violently with these substances.

Alkali Metals The alkali metals are very similar to one another and have very similar chemical and physical properties.

Alkali Metals The melting point of the alkali metals are very low compared with those of most other metals.

Alkali Metals The melting point of the alkali metals are very low compared with those of most other metals. Sodium, for example melts at 208ºF, less than the boiling point of water (212ºF).

Alkali Metals The melting point of the alkali metals are very low compared with those of most other metals. Sodium, for example melts at 208ºF, less than the boiling point of water (212ºF). Cesium melts at just over 82ºF, the temperature of a warm room.

Alkali Metals As pure elements, the alkali metals are much softer than most other metals.

Alkali Metals As pure elements, the alkali metals are much softer than most other metals. Cutting a block of alkali metal in half with a sharp knife does not take much effort.

Alkali Metals The most common alkali metals are sodium and potassium.

Alkali Metals The most common alkali metals are sodium and potassium. Although these metals are not found in pure form, they are very common in nature.

Alkali Metals The most common alkali metals are sodium and potassium. Although these metals are not found in pure form, they are very common in nature. For example, sodium combines with the element chlorine to form sodium chloride, which is familiar table salt.

Alkali Metals The most common alkali metals are sodium and potassium. Although these metals are not found in pure form, they are very common in nature. For example, sodium combines with the element chlorine to form sodium chloride, which is familiar table salt. Potassium, in the form of potassium compounds, is an important part of your diet and necessary nutrients for plants.

Alkaline Earth Metals The elements in Group 2 of the periodic table are the alkaline earth metals.

Alkaline Earth Metals The elements in Group 2 of the periodic table are the alkaline earth metals. As with the alkali metals, the alkaline earth elements all have similar properties.

Alkaline Earth Metals The elements in Group 2 of the periodic table are the alkaline earth metals. As with the alkali metals, the alkaline earth elements all have similar properties. They are very reactive metals, although not nearly as reactive as the alkali metals.

Alkaline Earth Metals The elements in Group 2 of the periodic table are the alkaline earth metals. As with the alkali metals, the alkaline earth elements all have similar properties. They are very reactive metals, although not nearly as reactive as the alkali metals. Most of the alkaline earths react with water, but not as vigorously as the alkali metals.

Alkaline Earth Metals The pure metals can burn in air if they are exposed to a flame.

Alkaline Earth Metals The pure metals can burn in air if they are exposed to a flame. The melting points of the alkaline earth metals are much higher than those of corresponding alkali metals but lower than those of many other metals.

Alkaline Earth Metals The pure metals can burn in air if they are exposed to a flame. The melting points of the alkaline earth metals are much higher than those of corresponding alkali metals but lower than those of many other metals. Magnesium melts at 1200ºF compared to 208ºF for sodium.

Alkaline Earth Metals Calcium and Magnesium are the most familiar alkaline earth metals.

Alkaline Earth Metals Calcium and Magnesium are the most familiar alkaline earth metals. Calcium is very important part of the human diet because calcium is a major component of bones and teeth.

Alkaline Earth Metals Calcium and Magnesium are the most familiar alkaline earth metals. Calcium is very important part of the human diet because calcium is a major component of bones and teeth. Magnesium is mixed with other metals to form alloys that are very light but stronger than steal.

Alkaline Earth Metals Calcium and Magnesium are the most familiar alkaline earth metals. Calcium is very important part of the human diet because calcium is a major component of bones and teeth. Magnesium is mixed with other metals to form alloys that are very light but stronger than steal. High-performance bicycles are built using an alloy of aluminum and magnesium.