Test Lead at Home: How to Identify Unknown Metals

In summary, the lead test strip showed inconclusive results due to the low concentrations of lead even if the test was followed to the letter. The lump is very much like lead, is heavy for its size, ductile, and can be marked with a knife. It is possible to precipitate lead out of solution with iodide ions. If lead is present, melting it in a can over a gas stove will result in lead being released.
  • #36
DaveC426913 said:
OK, I took my sample into my brother's lab to test its density.We measured its volume by dropping it in a full beaker of water and measuring the weight (and thus volume) of the water that was displaced on a microgram scale. By far the biggest problems we had were:
- eliminating the meniscus so we cold get an accurate water level, and
- ensuring that we drained all drops from the exteroir of the beaker onto the weight scale.

We used combinations of alcohol and/or hand soap to minimize the meniscus and used a microlitre pipette to recover any drops that lingered on the beaker. My brother, having spent decades in the lab, was able to estimate the few microlitre drops remaining and added them to the test sample. We figure we got our volume measurements to within +/-20 microlitres. We did the experiment 3 times.

Results:
The sample weighs 116.06g.
The volume is 10.13, 10.56 and 10.64 cm^3 for an average of 10.44 cm^3.

This results in a density of 11.12g/cm^3 +/- 0.02.

The published density of common lead is 11.34g/cm^3.

My measurement of the sample is within 2% of the density of lead.

I'm callin' it lead.
You could have a slug of "printer's lead". It was used for linotype printing and is cut with antimony (and perhaps a little tin) so that it is hard enough to resist deformation when making multiple impressions on a printing press, yet still re-melt easily for re-use.

Edit: hand-loaders love this stuff, since it can be easily cast into bullets, and it is "just" hard enough to shoot a (warning! Scientific term coming!) gazillion times without causing lead deposition in the grooves of a rifled barrel. Commercially, this tendency is overcome by jacketing bullets in copper or some other metal or alloy, but hand-loaders don't have the capability of producing jacketed bullets. Linotype lead is a precious (and shrinking) commodity.
 
Last edited:
Chemistry news on Phys.org
  • #37
turbo-1 said:
Linotype lead is a precious (and shrinking) commodity.
That is interesting. My brother also speculated that it might be precious, but for a different reason. He said something about low radioactive decay rate of a particular isotope that makes it useful for ... uh ... something to do with shielding.
 
<h2>1. What is the purpose of identifying unknown metals at home?</h2><p>The purpose of identifying unknown metals at home is to determine their chemical and physical properties, which can help in understanding their potential uses and applications. It can also be a fun and educational activity for science enthusiasts.</p><h2>2. What materials are needed for conducting a test lead at home?</h2><p>You will need a set of unknown metal samples, a magnet, a scale, a graduated cylinder, a beaker, hydrochloric acid, and a flame source (such as a Bunsen burner or a candle).</p><h2>3. How do you perform a flame test to identify unknown metals?</h2><p>To perform a flame test, you will need to heat up the end of a metal sample using a flame source. Observe the color of the flame and compare it to a color chart to identify the metal. Different metals produce different colored flames due to the emission of specific wavelengths of light.</p><h2>4. What is the process of using hydrochloric acid to identify unknown metals?</h2><p>When hydrochloric acid is added to a metal, it can produce a chemical reaction that releases hydrogen gas. The rate of reaction and the amount of gas produced can help in identifying the metal. For example, if a metal reacts quickly and produces a lot of gas, it is likely to be a reactive metal such as magnesium or zinc.</p><h2>5. Are there any safety precautions to take when conducting a test lead at home?</h2><p>Yes, it is important to wear protective gear such as gloves and safety glasses when handling chemicals and heating metal samples. It is also recommended to conduct the experiment in a well-ventilated area and to have a fire extinguisher nearby in case of any accidents. If you are unsure about the safety of a particular metal, it is best to avoid handling it and seek professional help.</p>

1. What is the purpose of identifying unknown metals at home?

The purpose of identifying unknown metals at home is to determine their chemical and physical properties, which can help in understanding their potential uses and applications. It can also be a fun and educational activity for science enthusiasts.

2. What materials are needed for conducting a test lead at home?

You will need a set of unknown metal samples, a magnet, a scale, a graduated cylinder, a beaker, hydrochloric acid, and a flame source (such as a Bunsen burner or a candle).

3. How do you perform a flame test to identify unknown metals?

To perform a flame test, you will need to heat up the end of a metal sample using a flame source. Observe the color of the flame and compare it to a color chart to identify the metal. Different metals produce different colored flames due to the emission of specific wavelengths of light.

4. What is the process of using hydrochloric acid to identify unknown metals?

When hydrochloric acid is added to a metal, it can produce a chemical reaction that releases hydrogen gas. The rate of reaction and the amount of gas produced can help in identifying the metal. For example, if a metal reacts quickly and produces a lot of gas, it is likely to be a reactive metal such as magnesium or zinc.

5. Are there any safety precautions to take when conducting a test lead at home?

Yes, it is important to wear protective gear such as gloves and safety glasses when handling chemicals and heating metal samples. It is also recommended to conduct the experiment in a well-ventilated area and to have a fire extinguisher nearby in case of any accidents. If you are unsure about the safety of a particular metal, it is best to avoid handling it and seek professional help.

Similar threads

  • Other Physics Topics
Replies
28
Views
3K
Replies
16
Views
2K
  • Engineering and Comp Sci Homework Help
Replies
1
Views
4K
  • Electrical Engineering
Replies
16
Views
2K
Replies
4
Views
811
Replies
13
Views
2K
  • Art, Music, History, and Linguistics
Replies
1
Views
1K
  • Materials and Chemical Engineering
Replies
6
Views
3K
Replies
2
Views
3K
Replies
9
Views
8K
Back
Top