C



Lab: Metals vs. Nonmetals (45 points)

Introduction: Elements can be classified in several ways, according to the similarities and differences in their properties. Two major classes of elements are metals and nonmetals. Everyday experience has given you some knowledge of metallic and nonmetallic properties.

Testable Question: Will we be able to classify an element as a metal or a nonmetal based on its physical and chemical properties alone?

Hypothesis: (5 points) What is your predicted answer to the testable question? Be sure to explain the reasons for your prediction here.

Procedure: (10 points) Summarize the procedure from each station in YOUR OWN WORDS

STATION #1: APPEARANCE (A-C)

List at least three Physical Properties (color, luster, odor, shape, etc.) for element samples A-C.

STATION #2: APPEARANCE (D-G)

List at least three Physical Properties (color, luster, odor, shape, etc.) for element samples D-G.

STATION #3: CRUSHING

Gently tap each element sample A-G with the hammer. Identify each as malleable (flattens without breaking), or brittle (breaks into pieces).

STATION #4: CONDUCTIVITY

Decide if each element sample A-G is a conductor or a nonconductor. Touch the element sample with the probes (wires), but do not allow the probes (wires) to touch each other. If the lightbulb goes on it is a conductor, if the lightbulb does not go on it is a nonconductor.

STATION: #5: REACTIVITY W/ACID (element samples A-C)

1. Add element samples A-C to the well plate.

2. Add exactly 5 drops of acid to each well.

3. Observe each well for 3 minutes. Record any changes or occurrences and decide whether the sample reacted with acid or not (changes include: color change or bubbling)

STATION: #6: REACTIVITY W/ACID (element samples D-G)

1. Add element samples D-G to the well plate.

2. Add exactly 5 drops of acid to each well.

3. Observe each well for 3 minutes. Record any changes or occurrences and decide whether the sample reacted with acid or not (changes include: color change or bubbling)

STATION: #7: REACTIVITY W/CuCl2 (element samples A-C)

1. Add element samples A-C to the well plate.

2. Add exactly 5 drops of CuCl2 to each well.

3. Observe each well for 3 minutes. Record any changes or occurrences and decide whether the sample reacted with CuCl2 or not (changes include: color change or bubbling)

STATION: #8: REACTIVITY W/CuCl2 (element samples D-G)

1. Add element samples D-G to the well plate.

2. Add exactly 5 drops of CuCl2 to each well.

3. Observe each well for 3 minutes. Record any changes or occurrences and decide whether the sample reacted with CuCl2 or not (changes include: color change or bubbling)

Data (10 points)

|Element |Appearance |Crushing |Conductivity |Reactivity w/Acid |Reactivity w/CuCl2 |

|A | | | | | |

|B | | | | | |

|C | | | | | |

|D | | | | | |

|E | | | | | |

|F | | | | | |

|G | | | | | |

Analysis Questions (10 points)

1. Classify each property tested as a physical property or a chemical property.

Appearance:

Conductivity:

Crushing:

Reactivity with acid:

Reactivity with CuCl2:

2. Sort the seven elements (A-G) into two groups (metals or nonmetals) based on similarities in their physical and chemical properties.

3. Which element or elements could fit into either group? Why?

4. Using the following information, classify each tested element A-G as a metal, a nonmetal, or a metalloid:

• Metals have a luster, are malleable, and conduct electricity

• Many metals react with acids; many metals react with copper chloride (CuCl2)

• Nonmetals are usually dull in appearance, brittle, and do not conduct electricity

• Metalloids have properties of both metals and nonmetals

Claims and Evidence (5 points)

Were you able to easily distinguish each element sample as a metal or a nonmetal? Provide evidence to support your conclusion.

Reflection (5 points)

What procedures in this investigation could lead to errors? How would each error affect your data?

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download