The Element Strontium

The Element Strontium
An Internet Hotlist on Strontium (Sr)

created by audreylewis09
Stoneleigh-Burnham School

Introduction | Basic Information | Uses of Strontium | Health Effects of Strontium | Useful Visual Aids

Introduction

Name: Strontium
Symbol: Sr
Atomic number: 38
Atomic mass: 87.62 amu
Melting point: 1050° K
Boiling point: 1655 K
Density: 2.64
Solid at room temperature
Silvery-gray in color
Alkaline Earth Metal
Reacts violently with air
Strontium carbonate (SrCO3) and strontium nitrate (Sr(NO3)2) burn with a strong red flame
Does not react with nitrogen below 653 K.
Strontium is not toxic in some isotopes, but the radioactive isotopes, when absorbed into the bones, can cause bone cancer and other bone disorders.
Some uses of strontium include: paliosalinity (where oceans were in the past), strontium isotope stratigraphy (determining how old soil is), making color television tubes, making the color red in flares and fireworks, and treating osteoporosis and other bone disorders (strontium is absorbed into bones like calcium, and has similar strengthening properties)
Strontium is found in nature, with a concentration in the ocean of 0.1 mg/L. It is also part of 40 common minerals, one of which is celestite.
Strontium is named after the town of Strontian in Scotland. It was originally thought to be a compound of barium or flourite. It was first identified as a new element by Thomas Charles Hope, who called it Strontianite.
Some interesting aspects of this element are that it is is similar to calcium in the way that it is absorbed into human bone. Another couple of interesting points are that strontium has both radioactive and stable isotopes, and the most common radioactive isotope (Strontium - 90) has a half-life of 29 years. A last interesting point is that because strontium is so unstable, it combusts in air.

Image from http://jchemed.chem.wisc.edu/jcesoft/CCA/CCA4/STILLS64/S_elt/Sr/Sr_element/2.JPG

The Internet Resources

Basic Information

Element: Strontium - Although this site doesn't seem to have much going for it at all, it really has some interesting facts that weren't mentioned in other articles, especially about the uses of strontium and natural occurrence of strontium. It also had two very useful links right on the page, which linked to strontium isotopic data and a nuclear periodic table (which would be useful to people looking for information on all the elements, not just strontium. One interesting thing I learned was that 98% pure strontium sells for $5 an ounce. I would rate this site a 3.5 out of five, because although it does not seem like it has a lot of good information on it, it really does, and was very helpful on the topic of strontium.
It's elemental - The element Strontium - This site did not have as much information about the history and the uses of strontium, but was more about the physical properties of the element. There was a little illustration of the periodic table, as well as many physical properties, like boiling point and density. One interesting point about strontium I found on this site was that the strontium-90 isotope was a common product of nuclear explosions. Although this site did not have that much about the history and other information, it had a lot about the elemental properties. I would rate this site 4 out of 5, because I learned a lot about the element Strontium, but not about the history, etc. of it.
Mineral Information Institute - Strontium - This was a nice website with also very basic information, just a little more in-depth; this was very similar to the previous website, with a reading level of probably high school, but very general information. This was mostly about the background and sources of strontium, not so much about uses or other properties of the element. One thing I learned was that some strontium is used to create special magnets, called ferrite ceramic magnets. I would rate this site a three out of five, because there was a lot of information on it, but not that much specific information.
Strontium - This page was short, but had a lot of information. The information on the site included bullet points on the history, forms, properties, isotopes, etc. One interesting piece of information from this included the fact that strontium was named after Strontian, a town in Scotland. I would rate this site a three out of five, because it had good information, but did not develop them at all, and really was very superficial information.
Strontium - element - Some of my teachers do not like Wikipedia, because there is no way of verifying the information off of it. However, I like Wikipedia because if the information I get off of it checks out, I know that it is accurate. One interesting piece of information I got off of this site was that strontium is the 15th most abundant element on Earth. I would rate this site four out of five, because although there is no way of making sure all the information on this site is completely accurate, there is a lot of good information on it too.
The Element Strontium (Sr) - I really liked this site – it had a very interesting piece about the history of strontium, and had some good information about the history of strontium and the occurrence of strontium in the world. This is a good site for someone my age, or maybe a college student, just looking for basic information about strontium. One interesting fact I learned from this site was that before strontium was identified as a new element, mineralogists thought it was fluorite or barium sulfate. I would rate this site a four out of five, because the information in it was all good and useful, but there could have been more information altogether – it was a pretty short website.

Uses of Strontium

Marine Strontium Isotope Studies - This was a site about paleosalinity. It was a pretty short website, but very informative about one of the more esoteric uses of strontium. It was a pretty good website – a bit confusing sometimes, but usually was very informative. Although it was a little confusing, it really explained what paleosalinity was to someone like me, who did not understand it or know what it was. One interesting fact I learned from this site was that fresh water has much less strontium than seawater. I would rate this site three out of five, because this was informative, but I could only apply it to one aspect of my powerpoint, and not to the rest of my hotlist.
Strontium Isotope Stratigraphy - There was not that much about this topic, which was strontium isotope stratigraphy. This is the study of how old soil is, by looking at sedimentary layers, and helps people decide where to drill/explore for underground reservoirs. This was a very complicated topic, which I did not know anything about, but I was able to figure out what the basics were off this introduction to it. Although I liked the way this site was set up, it was more of a research-in-progress site, which was not quite as helpful. One interesting thing I learned from this site was that strontium works as a chemical tracer. I would rate this site a two out of five, because it was very confusing sometimes, and the more technical terms were hard to wade through.
Strontium and Osteoporosis - This was a very specialized site, about the recent breakthrough which uses strontium to treat osteoporosis. Although radioactive strontium (which the previous site was all about) is harmful, there are other kinds of strontium that actually work to strengthen bones. This was very interesting – lab rodents that had strontium administered through their drinking water had markedly larger and thicker teeth, and thicker and stronger bones. This information surprised me – I had previously thought that the effects of strontium in bones would be mostly negative. One thing I learned from this site was that strontium in doses of up to 1.7 g/day helped prevent and reverse osteoporosis. I would rate this site a 3.5 out of five, because while the information was all good and interesting, it was mostly medical, not quite as much chemistry as I had hoped.
Strontium in Fireworks - According to this site, strontium is put in fireworks (as well as police flares and other pyrotechnics), to make them a red color. This site was more about fireworks in general than strontium, but was still interesting, and some of the information could be put in when I talk about the uses of strontium. One interesting fact that I learned from this site was that both purple and red had strontium salts in them. I would rate this site a two out of five, because this site really didn’t have that much about strontium, and was more about fireworks, so I really wasn’t able to use it that much.

Health Effects of Strontium

FAQs about the Health Effects of Strontium - This site was all about the health effects and toxicity of strontium. It was nice because it addressed the main questions about strontium, and was not just unrelated information that you had to wade through to find the answer to one question, which really helps, especially with research. Most of these were about the health risks of strontium, and were so not too helpful with my kind of research, but were still pretty interesting for researching how strontium is in the natural world. One interesting thing I learned from this website was that high amounts of radioactive strontium can damage bone marrow. I would rate this site a three out of five, because it was very useful, but when it can down to it, did not have as much information as some of the other sites did.
Strontium - nuclear data - This site was more about the chemical element strontium, like my first couple of sites. It had several charts, but not much written description of strontium. There were a lot of simple mathematical facts about strontium, especially the nuclear data about strontium. Some of these facts I didn’t understand, because they had complicated units and technical terms that I really didn’t get. One interesting fact I learned from this website was that strontium has a melting point of 1041 K. I would rate this site a three out of five, because this site was very helpful with basic facts about strontium. I think it was a good site for someone like me, who didn’t know much about strontium, but wanted to know more, but it would be better for the reader to know more about chemistry and some of the terms used with it.
Strontium and Radioactivity - This site was a pdf file about strontium, with a focus on strontium’s radioactive properties. This was a really good site – it had a lot of information, especially with helping me by looking at charts and graphs. There was even an equation about the lifetime cancer mortality risk, through ingestion or inhalation! Not only did this site go in depth about radioactive isotopes of strontium (especially strontium-90), but it also covered strontium in the environment, and uses of strontium. One thing I learned from this site was that strontium-90 has a half life of 29 years. I would rate this site a 4.5 out of five, because it was very helpful, and definitely helped the part of my research about strontium in the body, and radioactive isotopes of strontium.

Useful Visual Aids

Pictures and Videos of Strontium - This site was mostly pictures, and did not have much in words about strontium. What I did like about this website was that although it did not have a lot of written material, it had many images, and three videos. There were some basic pictures of strontium, showing what it looked like. The three videos were also really good – they showed what happened when strontium was exposed to air, to water, and to acid. One thing I learned was that strontium is a dark, crystal-looking thing. I would rate this site a 3.5 out of five, because although the videos were helpful, there was not much else, and nothing written about strontium to help me interpret the videos and images.
Visual Elements - Strontium - Although at first glance it looks like this site does not have that much to offer, there was some good information about the history of strontium. There are also a link on it which was to more about the actual chemical element Strontium. This site would be good for people who were not looking for very specific things about Strontium, but for basic information. One thing I learned about was that Strontium-90, an isotope created by a nuclear explosion, was dangerous because it could be absorbed into the bones of small children. I would rate this site a three out of five, because it all had good valid information, but most of the information on this site I could find on different sites.

Content by audreylewis09, alewis@sbschool.org
http://www.kn.att.com/wired/fil/pages/liststrontiuau.html
Last revised Thu Jan 3 13:57:37 US/Pacific 2008