The Age of the Earth

The cells are magnified x10, If you grew x10, , you could place your feet in Seattle and touch Perth, Australia with your hands. Iron in hemoglobin carries oxygen around our bodies. Scrap iron and steel for recycling. How times have changed; iron was once worth eight times more than gold. Discovery of Iron Iron has been known since ancient times. The first iron used by humans is likely to have come from meteorites. Iron corrodes easily, so iron artifacts from ancient times are much rarer that objects made of silver or gold. This makes it harder to trace the history of iron than the less reactive metals.


At the time that Darwin’s On the Origin of Species was published, the earth was “scientifically” determined to be million years old. By , it was found to be 1. In , science firmly established that the earth was 3. Finally in , it was discovered that the earth is “really” 4.

Strontium is itself radioactive, having a half-life of 30 years, before it emits a beta particle and decays into Yttrium, with a half life of a few days, after which it emits a beta particle to turn into the stable Zirconium

History of Technology Heroes and Villains – A little light reading Here you will find a brief history of technology. Initially inspired by the development of batteries, it covers technology in general and includes some interesting little known, or long forgotten, facts as well as a few myths about the development of technology, the science behind it, the context in which it occurred and the deeds of the many personalities, eccentrics and charlatans involved.

You may find the Search Engine , the Technology Timeline or the Hall of Fame quicker if you are looking for something or somebody in particular. Scroll down and see what treasures you can discover. Background We think of a battery today as a source of portable power, but it is no exaggeration to say that the battery is one of the most important inventions in the history of mankind.

Volta’s pile was at first a technical curiosity but this new electrochemical phenomenon very quickly opened the door to new branches of both physics and chemistry and a myriad of discoveries, inventions and applications. The electronics, computers and communications industries, power engineering and much of the chemical industry of today were founded on discoveries made possible by the battery. Pioneers It is often overlooked that throughout the nineteenth century, most of the electrical experimenters, inventors and engineers who made these advances possible had to make their own batteries before they could start their investigations.

They did not have the benefit of cheap, off the shelf, mass produced batteries. For many years the telegraph, and later the telephone, industries were the only consumers of batteries in modest volumes and it wasn’t until the twentieth century that new applications created the demand that made the battery a commodity item. In recent years batteries have changed out of all recognition. No longer are they simple electrochemical cells.

J. Laurence Kulp: Wikis

This new method has been used to perform a detailed Radiation levels in food predicted June 14, Food in Japan will be contaminated by low-level radioactivity for decades following the Fukushima nuclear disaster, but not at a level which poses a serious risk to human health, according to new research. Radioactive leaks top priority at Fukushima: Oats to clean up heavy metals in contaminated soil February 6, Researchers from universities in China, Switzerland and Australia have identified that the naked oat is best suited to remove radioactive strontium from contaminated soils.

Paper spotlights key flaw in widely used radioisotope dating technique January 31, An oversight in a radioisotope dating technique used to date everything from meteorites to geologic samples means that scientists have likely overestimated the age of many samples, according to new research from North Carolina

Knowledge of the half-life of an isotope is useful in almost all calculations involving tracer isotopes. It also leads to an interesting use for naturally occurring isotopes: dating of ancient objects.

May 20, Strontium also plays an important role in figuring out the origins of species: Anthropologists measure the levels of strontium ions in bones and teeth to help determine the geographic origins of ancient humans and animals. While natural strontium is harmless, one of its isotopes, Sr , carries a more sinister reputation: Highly reactive Strontium is quite common in nature — it is the 15th most abundant element in Earth’s crust, according to the Minerals Education Coalition MEC.

Strontium occurs in about 0. Natural strontium is a mixture of four stable isotopes — Sr , Sr , Sr and Sr — and is primarily found within the minerals celestite and strontianite. Like other alkali metals, strontium is highly reactive chemically and reacts with both air and water. When exposed to air, it burns with a bright red flame. When combined with water, strontium gives off hydrogen gas and strontium hydroxide — a strong irritant.

While natural strontium is stable and not hazardous to health, the synthetic Sr isotope is radioactive and a dangerous component of nuclear fallout. World resources of strontium are thought to exceed 1 billion tons, according to the USGS. The primary producers of strontium as celestine are China and Spain, followed by Mexico, Argentina and Morocco.

Although strontium deposits occur widely in the United States, they have not been mined since

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Louis, March 15, Sun streamed in through a stained glass window of the chapel at Washington University in St. Louis, Missouri on a pleasant and sunny Wednesday afternoon in mid-May About 1, people listened to Linus Pauling, the Nobel Laureate in Chemistry, deliver a fiery speech urging an end to nuclear weapons testing.

Radioactive iodine (which gets into the thyroid gland) cerium, caesium, zirconium, niobium and ruthenium, along with americium, strontium 90 (which gets into the bones) and plutonium (which gets.

The Radiometric Dating Game Radiometric dating methods estimate the age of rocks using calculations based on the decay rates of radioactive elements such as uranium, strontium, and potassium. On the surface, radiometric dating methods appear to give powerful support to the statement that life has existed on the earth for hundreds of millions, even billions, of years. We are told that these methods are accurate to a few percent, and that there are many different methods.

We are told that of all the radiometric dates that are measured, only a few percent are anomalous. This gives us the impression that all but a small percentage of the dates computed by radiometric methods agree with the assumed ages of the rocks in which they are found, and that all of these various methods almost always give ages that agree with each other to within a few percentage points.

Since there doesn’t seem to be any systematic error that could cause so many methods to agree with each other so often, it seems that there is no other rational conclusion than to accept these dates as accurate. However, this causes a problem for those who believe based on the Bible that life has only existed on the earth for a few thousand years, since fossils are found in rocks that are dated to be over million years old by radiometric methods, and some fossils are found in rocks that are dated to be billions of years old.

Half life question (again).. help please!?

For example, why are some radioisotopes, such as uranium , found in nature, whereas others are not and must by synthesized? The key to answering this question is to realize that different nuclei undergo radioactive decay at different rates. Many radioisotopes decay essentially completely in a matter of seconds or less; obviously, we do not find such nuclei in nature.

06/07/TM 1 RADIOISOTOPES IN EVERYDAY LIFE Radioactive materials are used in a wide variety of applications in everyday life. Research laboratories, medical centers, industrial.

Biological activity[ edit ] Strontium is a ” bone seeker ” that exhibits biochemical behavior similar to calcium , the next lighter group 2 element. Exposure to 90Sr can be tested by a bioassay , most commonly by urinalysis. However, by averaging all excretion paths, the overall biological half life is estimated to be about 18 years. As strontium has an affinity to the calcium-sensing receptor of parathyroid cells that is similar to that of calcium, the increased risk of liquidators of the Chernobyl power plant to suffer from primary hyperparathyroidism could be explained by binding of strontium Controlled amounts of 90Sr and 89Sr can be used in treatment of bone cancer.

It is also used as a radioactive tracer in medicine and agriculture.

Radioactive Decay: A Sweet Simulation of Half-Life

Periodic Table of Elements Provides comprehensive data for each element of the periodic table of elements including up to 40 properties, names in 10 languages and common chemical compounds. Information also provided for 3, nuclides and 4, nuclide decay modes. Some chemicals in this database contain more information than others due to the original reason this information was collected and how the compilation was accomplished. While working with material safety data sheets MSDS , I found that manufacturers sometimes used obscure names for constituent chemicals and I didn’t always have a good idea of what I was dealing with.

1. What Is Radioactive Material? Figure 1. The Atom R adioactivity is a part of nature. Every thing is made of atoms. Radioactive bon that is used in carbon dating as well as bio- half-life = 28 years Strontium half-life = 64 years Yttrium stable Zirconium Figure 2.

Bulk properties[ edit ] Thorium is a moderately soft , paramagnetic , bright silvery radioactive actinide metal. In the periodic table , it lies to the right of actinium , to the left of protactinium , and below cerium. Pure thorium is very ductile and, as normal for metals, can be cold-rolled , swaged , and drawn. Aluminium ‘s is In the beginning of period 7 , from francium to thorium, the melting points of the elements increase as in other periods , because the number of delocalised electrons each atom contributes increases from one in francium to four in thorium, leading to greater attraction between these electrons and the metal ions as their charge increases from one to four.

After thorium, there is a new downward trend in melting points from thorium to plutonium , where the number of f electrons increases from about 0. The major impurity is usually thorium dioxide ThO2 ; even the purest thorium specimens usually contain about a tenth of a percent of the dioxide. Addition of small proportions of thorium improves the mechanical strength of magnesium , and thorium-aluminium alloys have been considered as a way to store thorium in proposed future thorium nuclear reactors.

Thorium forms eutectic mixtures with chromium and uranium, and it is completely miscible in both solid and liquid states with its lighter congener cerium. Isotopes of thorium All but two elements up to bismuth element 83 have an isotope that is practically stable for all purposes “classically stable” , with the exceptions being technetium and promethium elements 43 and All elements from polonium element 84 onward are measurably radioactive. Four-fifths of the thorium present at Earth’s formation has survived to the present.

It is one of only three radioactive elements along with protactinium and uranium that occur in large enough quantities on Earth for a standard atomic weight to be determined.

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It rapidly reacts in air to take on a yellowish colour; therefore, it must be protected from oxygen for storage. It does not occur free in nature. Although it is widely distributed with calcium , there are only two principal ores of strontium alone, celestine SrSO4 and strontianite SrCO3. A mineral from a lead mine near the village of Strontian, in Argyll, Scotland , was originally misidentified as a type of barium carbonate , but Adair Crawford and William Cruickshank in noted that it was likely a different substance.

The metal was isolated by Sir Humphry Davy , who electrolyzed a mixture of the moist hydroxide or chloride with mercuric oxide, using a mercury cathode , and then evaporated the mercury from the resultant amalgam.

May 13,  · Strontium Complete table of nuclides General Name, symbol Strontium, Sr Neutrons 52 Protons 38 Nuclide data Natural abundance syn Half-life years Decay products Y Decay mode Decay energy Beta decay MeV Strontium (90 Sr) is a radioactive isotope of strontium produced by nuclear fission, with a half-life of years.

Radiometric dating is a means of determining the “age” of a mineral specimen by determining the relative amounts present of certain radioactive elements. By “age” we mean the elapsed time from when the mineral specimen was formed. Radioactive elements “decay” that is, change into other elements by “half lives. The formula for the fraction remaining is one-half raised to the power given by the number of years divided by the half-life in other words raised to a power equal to the number of half-lives.

To determine the fraction still remaining, we must know both the amount now present and also the amount present when the mineral was formed. Contrary to creationist claims, it is possible to make that determination, as the following will explain:

Iron Element Facts

Natural[ edit ] On Earth, naturally occurring radionuclides fall into three categories: Radionuclides are produced in stellar nucleosynthesis and supernova explosions along with stable nuclides. Most decay quickly but can still be observed astronomically and can play a part in understanding astronomic processes. Some radionuclides have half-lives so long many times the age of the universe that decay has only recently been detected, and for most practical purposes they can be considered stable, most notably bismuth It is possible decay may be observed in other nuclides adding to this list of primordial radionuclides.

Secondary radionuclides are radiogenic isotopes derived from the decay of primordial radionuclides.

The alkaline earth metal strontium (38 Sr) has four stable, naturally occurring isotopes: 84 Sr (%), 86 Sr (%), 87 Sr (%) and 88 Sr (%). Its standard atomic weight is (1).. Only 87 Sr is radiogenic; it is produced by decay from the radioactive alkali metal 87 Rb, which has a half-life of × 10 10 years (i.e. more than three times longer than the current age of the.

Oxidized dendritic strontium Strontium is a grey, silvery metal that is softer than calcium and even more reactive in water , with which it reacts on contact to produce strontium hydroxide and hydrogen gas. It is kept under a liquid hydrocarbon such as mineral oil or kerosene to prevent oxidation ; freshly exposed strontium metal rapidly turns a yellowish color with the formation of the oxide.

Finely powdered strontium metal is pyrophoric meaning it will ignite spontaneously in air at room temperature. Volatile strontium salts impart a bright red color to flames , and these salts are used in pyrotechnics and in the production of flares. Natural strontium is a mixture of four stable isotopes. Considering it a peculiar earth I thought it necessary to give it an name.

I have called it Strontites, from the place it was found; a mode of derivation in my opinion, fully as proper as any quality it may possess, which is the present fashion.

Element Online Dating Profiles

While there are numerous natural processes that can serve as clocks, there are also many natural processes that can reset or scramble these time-dependent processes and introduce uncertainties. To try to set a reasonable bound on the age, we could presume that the Earth formed at the same time as the rest of the solar system.

If the small masses that become meteorites are part of that system, then a measurement of the solidification time of those meteorites gives an estimate of the age of the Earth. The following illustration points to a scenario for developing such an age estimate. Some of the progress in finding very old samples of rock on the Earth are summarized in the following comments. It is a compound of zirconium, silicon and oxygen which in its colorless form is used to make brilliant gems.

Dating of a hydrothermal event related to ore formation was conducted initially by dating the granite that was regarded as the heat source for the hydrothermal activity and assuming that ore deposition occurred contemporaneously with emplacement of the granite.

Ruthenocuprates are in a sense a hybrid of superconducting cuprates and the strontium ruthenate. HE – Ultra-Metal-Poor and Carbon-Rich Up to this point, the observed sequence of phase transitions in strontium and the predicted sequence in calcium are identical: The next higher-pressure phase of strontium, Sr-V, is an incommensurate host-guest structure. Exotic behavior and crystal structures of calcium under pressure Observation of the incommensurate barium-IV structure in strontium phase V.

Exotic behavior and crystal structures of calcium under pressure It is known that some as-grown ferroelectric crystals, such as strontium barium niobate SBN [Fig. Random quasi-phase-matched second-harmonic generation in periodically poled lithium tantalate Japan 65 Dunn K J and Bundy F P Pressure-induced superconductivity in strontium and barium Phys. Assembling the puzzle of superconducting elements: Single barium ion spectroscopy: Nematic orders in Iron-based superconductors The strontium uncertainty in the plot is a factor of 2 larger than published in.

The pseudogap in high-temperature superconductors:

Strontium 90 – Electron Romance