Metals or Non-metals Lab Report

Metal or Nonmetal

7/9/13

Georgie Dorfman, Ben Cohen, and Charlie Dorfman

Dr. Foreman

Abstract:

My group and I identified the unknown elements as either a metal, metalloid, or a nonmetal. We did this by preforming 5 different tests. We tested for physical properties or chemical properties. To test the physical properties we recorded the appearance of the elements (luster or dull) and we crushed the elements with a hammer to see if the element were brittle (break), or if they were malleable (would not break). To test for the chemical properties we tested for the presence of conductivity and for the recording of reactivity with hydrochloric acid and copper chloride.

Significance of lab:

This lab gave me a better understanding on how to distinguish the difference between metals, metalloids, and nonmetals. I learned that you cannot distinguish between metals and non-metals by judging its appearance. There are important tests that have to take place to test between the two. 

Purpose:

The purpose of this lab is to test un-known elements and determine whether each element is a metal, metalloid, or a nonmetal.

Procedure:

1. Create a data table including six columns, including the elements and the properties we are testing for

2. Record the appearance of each element 

3. Use an electrical conductivity apparatus and touch both electrodes to the element sample

4. Record if the element is a conductor or a nonconductor

Non-conductor

 

Conductor

5. Gently tap each element with a hammer

6. Record if the element is malleable (flattens, but doesn't shatter) or brittle (shatters into pieces)

Brittle

Malleable

7. Reactivity with copper chloride:

-Label seven wells in a well-plate A-G

-Put a sample of each element into each well

- Add 15-20 drops of 0.1 M copper chloride to each sample

-Allow the sample to sit for 5 minutes

-Observe and record a change in the sample's appearance and see if the elements reacted with the copper chloride

reaction with copper chloride

8. Put the well plate to the side
9. Get a new well plate
10. Reactivity with acid:

              -Label seven wells in the clean well-plate A-G

              -Place a sample of each element into a separate well

              -Add 15-20 drops of 0.5 M HCl to each sample

-Allow the sample to sit for 5 minutes

-Observe and record if there is a formation of gas bubbles and if there is a reaction with the hydrochloric acid

reaction with hydrologic acid

-Discard both well-plates

-Wash your hands thoroughly 

Results:

My group and I had a hard time deciding which elements were metals, nonmetals, or metalloids. From our five observations, it was easy to detect if the elements were either metals or nonmetals because they have very distinct results. Identifying if each element is a metalloid was more difficult because metalloids are a mixture of both metals and nonmetals, so a slight mistake in a step could lead to the belief that the element is a metalloid. This was difficult because some elements conducted electricity, but could easily shatter like elements D and G. Some elements could not conducted electricity, but were malleable at the same time like element A. Comparisons like this gave us a hard time. With all these different results, my group and I finally were able to decide which unknown elements were metals, metalloids, or nonmetals. We came to the conclusion that elements A, C, and F were metals, elements B, D, and G were metalloids, and element E was a nonmetal.

Class aggregated data:

There is a variation in results. For element A, most groups concluded that it was metal, while the group Carbon concluded it was a nonmetal. For element B, there was an even number of results of metalloids and metals. For element C, most groups concluded that the element was a metal. For element D, the results varied between metals, nonmetals, or metalloids. For element E, most groups concluded that the element was a nonmetal. For element F, all groups concluded that this element was a metal. For element G, the results varied between metals, metalloids, and nonmetals. With the confusion of metalloids, the results varied because of the close difference it makes.

Lab Questions:

1. The physical properties tested were the appearance and the crushing of the element. The chemical properties were conductivity and the reactivity with copper chloride and hydrochloric acid.

2. The first group unknown elements are the metals. This group consists of elements A, C, and F. The second group of the unknown elements are called the nonmetals. This group consists of one element E.

3. The elements that could fit into either group are elements B, D, and G. These elements are metalloids. These elements look luster and conduct electricity, but they are brittle and don't react with the two solutions. And some of these elements may look dull, but actually conducts electricity. This makes them metalloids.

4. The metals are elements A, C, and F. The metalloids are elements B, D, and G. The nonmetal is element E.