Eleanor Mathis

Science Skills and Reasoning 

1st Period

June 28, 2007

Time:

50 minutes

Objectives:

The student will distinguish between metals, non-metals, and metalloids.

The student will compare and contrast the physical and chemical properties of each.

(MS Framework 4a)

Materials:

Overhead, transparency sheets, vis-à-vis pens,

Do Now:

(Written on overhead transparency)

List 3 physical properties and 3 chemical properties each for this key and this piece of cotton cloth.

Set:

1. "Today we are going to continue talking about physical and chemical properties, but now we are going to use them to distinguish between metals and non-metals and a funny group of elements called metalloids."

2. "Metals are pretty common.. I bet you can name me a few already." Have students give examples of metals.

3. Teacher will read a list of metals, some commonly recognizable as metals, and other metals that don't sound like metals. Students will raise their hands to indicate whether they think it is a metal or a non-metal, and teacher will write the name in a chart on the board.

-calcium, magnesium, sodium, potassium, nickel, iron, copper, zinc, gold, platinum, silver, lithium

4. Teacher will reveal that all of them are in fact metals,  so we will have to look a little bit closer at metals and non-metals' properties to REALLY classify them, which we will be able to do by the end of the day.

Procedures:

1.  Tell students the three ways we can distinguish between metals and non-metals- looking at their place on the periodic table, looking at what their electrons do, and what their physical and chemical properties are.

2. "But first..." Have students copy definitions from overhead into their notes of metals ( substance with high electrical conductivity, luster, and malleability, which readily loses electrons to form positive ions) and non-metals (characteristics opposite those of metals, tends to gain electrons)

3. Have student refer back to their periodic table chart, and draw in the dividing lines between metals and non metals on their chart as teacher does it on the overhead.

4. Ask students to identify elements as metals or non-metals based on the lines they drew.

5. Now, the second way- remind students of earlier conversation about opposites attracting- metals have something that non-metals don't, so they get together. Tell students definition of "mettle"- vigor/strength of spirit- to help them remember that metals are the ones "exuding" something- strength or electrons.

6. Independent practice from overhead- have students answer whether an element is a metal or non-metal based on description of gained/lost electrons in bonding between metal and non-metal (Ex. zinc lost an electron and oxygen gained one to form zinc oxide. Which is the metal/non-metal?)

7. Now, the third way. Remind students of the key and the cloth from the do-now. Tell them to think about those as the teacher reads physical and chemical properties of metals and non-metals, and the students put them in a chart on the board (metal/non-metal columns), thus classifying the properties. Check at the end by going through the chart and asking if the properties apply to the key and the cloth.

Physical Properties of Nonmetals:

• No luster (dull appearance)
• Poor conductor of heat and electricity
• Brittle (breaks easily)
• Not ductile
• Not malleable
• Low density
• Low melting point

Chemical Properties of Nonmetals:

• Tend to gain electrons

Physical Properties of Metals:

• Luster (shininess)
• Good conductors of heat and electricity
• High density (heavy for their size)
• High melting point
• Ductile (most metals can be drawn out into thin wires)
• Malleable (most metals can be hammered into thin sheets)

Chemical Properties of Metals:

• Easily lose electrons
• Corrode easily. Corrosion is a gradual wearing away. (Example: silver tarnishing and iron rusting)

8. "Last but not least..." Those silly metalloids. Use "droid"- humanlike robot" as an example of the kind of elements metalloids are- not quite metal, not quite non-metal.. The wishy washy elements... Tie back to relationship example- you don't care that much about bonding with someone who doesn't commit)

9. Point out metalloids on periodic table, and have students write characteristics in their notes as teacher reads them aloud.

Metalloids

Elements on both sides of the zigzag line have properties of both metals and nonmetals. These elements are called metalloids.

Physical Properties of Metalloids:

• Solids
• Can be shiny or dull
• Ductile
• Malleable
• Conduct heat and electricity better than nonmetals but not as well as metals

10. If time remaining, have students start on homework- List 5 metal and 5 non-metal items in your house, and give me one characteristic of each that makes you think that it is metal or non-metal.

Closure:

1. Have students say again what properties of the key and the cloth make them metal/non-metal.

2. Review: Have students verbally list more characteristics of metals/non-metals- make sure they get chemical ones.

3. Next time we're going to start looking closer at how we measure elements- Ask students to remind you which kind of property measurement is (physical)

4. Dismissal.

Assessment/Evaluation:

-The teacher will observe (M) the student distinguish between and compare/contrast metals and non-metals.  (C).

-The teacher will administer a quiz the following day (M) requiring the student to distinguish between a metal and a non-metal (C) and the grade will be recorded in the grade book (D).