Teaching students about different bond types can be boring, unless you incorporate real-life examples and interesting media. This article series shows you how to take covalent bonding to new levels in your chemistry classroom.
When to Use
NOVA has produced a video, The Diamond Deception, that does a remarkable job of showing students how diamonds can be made by machine. They are not fake diamonds, they are synthetic diamonds. The difference is spelled out in the video.
I recommend that before you show your students "The Diamond Deception," you should discuss the fundamentals of covalent bonding. The material in the video will serve as an extension or application of what you have done in the classroom.
One of my favorite pre-viewing activities is to ask the students, "What is the difference between diamond and graphite?" This will lead to a discussion of the element carbon. I will incorporate models of the two different substances into the discussion, and end by pointing out that the main difference is the strength and number of bonds in each substance. After this, we are ready to watch the video.
- List 2 things that make diamonds “magical."
- How did Antoine Lavosier (in the late 1700s) prove that diamonds were pure carbon?
- What is the main difference between diamond and graphite?
- What was the goal of GE’s project Superpressure?
- Why was the metal troilite in the meteor important?
- Why couldn’t these first tiny crystals made by GE ever be gems?
- How does DeBeers protect the value of diamonds?
- What is an inclusion and why does it matter?
- Explain how the man-made diamonds end up with a brown-colored tint.
- Explain the role of a nitrogen "getter."
- Faced with a potential _________________________________ caused by the new synthetics that are undetectable under a microscope, De Beers has been forced to look at the ______________________________of natural and synthetic diamonds to find the tiniest difference.
- How do natural and synthetic diamonds act differently after being placed under a UV light?
- What low-tech way is DeBeers using for diamond detection?
- Which would you buy, a big synthetic diamond or a small natural one? Why?
1. Things that make diamonds magical are their age (3 billion years old), the enormous effort needed to find and get them, and their magnificent way of dealing with light.
2. Lavoisier burned a diamonds completely...all that was left was carbon dioxide gas. This proved that diamonds were pure carbon.
3. The main difference between diamond and graphite are their structures. Graphite has weak bonds between layers, whereas diamond is bonded in all directions.
4. The goal of GE's project Superpressure was to make the world's first industrial diamonds.
5. The metal troilite in the meteor was important because the folks at GE hoped it could be heated and used as a solvent for graphite.
6. The GE crystals would never be gems because they were imperfect.
7. DeBeers protects the value of diamonds by controlling the release of diamonds into the market.
8. Inclusions are tiny minerals trapped at the time of diamond formation that affect the value of the diamond.
9. The man-made diamonds ended up with a brown tint because nitrogen from the atmosphere got into the presses.
10. A nitrogen "getter" chemically attracts nitrogen away from the growing diamond.
11. Faced with a potential crisis caused by the new synthetics that are undetectable under a microscope, DeBeers has been forced to look at the atomic structure of natural and synthetic diamonds to find the tiniest difference.
12. Under a UV light, synthetic diamonds glow, while natural ones do not.
13. DeBeers is putting a stamp on the diamond...a minute logo.
After the video, spend time with students discussing the difference between man-made and fake diamonds. Students will often think of cubic zirconia and will not realize that the diamonds made in the video are real diamonds...they were only produced in a location other than the earth.
Points of interest:
- The synthetic jeweler featured in the video has a website. Look up Gemesis corporation to see the array of synthetic diamonds available.
- Life Gems are diamonds that are made using the remains of loved ones! (Pets or relatives.)
- Blood Diamonds were made famous by Leonardo DiCaprio's movie of the same title. The idea that people may be dying to get you that big diamond is enough to prompt some people to buy synthetic diamonds instead.
It really is amazing that chemistry can produce these man-made diamonds, and that the chemical properties of diamonds have such far-reaching effects!