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 why do transition metals have variable oxidation states

why do transition metals have variable oxidation states

What is a Transition Metal? The periodic table is filled with fascinating elements. For example, did you know: в Nearly all of the earth's core is made of iron. в Vanadium is named after a Scandinavian goddess. в Although it's highly toxic, people used to use mercury as a cure-all for a whole list of aliments. So, other than being neat, what do iron, vanadium, and mercury have in common? Wellв I'm so glad you asked. These are three of the transition metals, found in groups 3 through 12 on the periodic table. These metals have varying oxidation states which can make them a little confusing. Wait, oxidation states? Yep, let's check it out! In order to understand transition metals, we need to delve into oxidation states, (which are sometimes referred to as oxidation numbers). These are

 why do people put black lines under their eyes

why do people put black lines under their eyes

One of the earliest known instances of a player wearing eye black is baseball legend, who, in or around the 1930s, used the grease in an attempt to reduce sun glare. According to Paul Lukas of, eye black caught on with player. He also states that the original eye black was made from the ashes of burned cork. A 2003 study by Brian DeBroff and Patricia Pahk tested whether black eye grease actually had anti-glare properties. The subjects of the study were divided into three groups: wearers of eye black, wearers of anti-glare stickers, and wearers of. The subjects' vision was tested using an while being exposed to natural sunlight. The study concluded that eye black reduced glare of the sun and improved sensitivity, whereas commercial anti-glare stickers and petroleum jelly (the control

 why do trees change color in the fall

why do trees change color in the fall

The vivid yellow and orange colors of fall leaves have actually been there throughout the spring and summer, but we havenБt been able to see them. The deep green color of chlorophyll, which helps plants absorb life-giving sunlight, hides the other colors. In the fall, trees break down the green pigments and nutrients stored in the leaves. The nutrients are shuttled into the roots for reuse in the spring As leaves lose their chlorophyll, other pigments become visible to the human eye, according to Bryan A. Hanson, professor of chemistry and biochemistry at DePauw University who studies plant pigments. Some tree leaves turn mostly brown, indicating that all pigments are gone. Burgundy and red colors are a different story. Dana A. Dudle is a DePauw professor of biology who researches red

 why do veins have one way valves

why do veins have one way valves

Most of our blood volume is carried in the veins (64%). Veins can expand to hold large amounts of blood. Veins are blood vessels that carry blood from the body back to the heart. Blood return from the legs occurs mainly through the deep veins. Within the veins, especially those of the legs are valves. Venous valves are bicuspid (two) flap like structures made of elastic tissue. The valves function to keep blood moving in one direction. The flow of blood in the venous system is complex for several reasons: the low pressure within the veins, flow rates that vary from high (during muscle contraction) to almost no flow during quiet standing or sitting positions, the effects of gravity, the collapsible nature of the venous wall, the presence of valves, and the large volume of blood carried in

 why do people get married so young

why do people get married so young

Not saying it is a bad thing, but it does seem rather peculiar to me. I have several cousins from the south and for all of them it seems like if you aren't married by 25 you're an old maid. You know the saying "ring by spring" to refer to the spring semester of a girl's senior year of college. well, at least in my experience that has totally panned out. I, being a non-southerner, don't quite understand the mentality. If you love someone, I don't see why waiting a couple of years or so to tie the knot will change anything. But then again, I subscribe to a different viewpoint. IF you answer that it's societal expectations or societal pressure, I agree, but I'm looking for something a little deeper than that. For example, do you think that in southern society people are expected to be

 why do tomatoes rot on the vine

why do tomatoes rot on the vine

When you have plenty of tomatoes on your plants, but some of them look like they are rotting on the vine, your tomatoes are suffering fromВblossom end rot. The first sign is a brown discoloration near the bottom end of the fruit. These spots grow and darken until they cover up to half of the tomato, and the rotting fruit becomes vulnerable to secondary bacteria and fungi. The affected tomatoes can t be saved, but the plant can. Blossom end rot is the result of calcium deficiency. However, that doesn t necessarily mean that you need to add calcium to your soil. Blossom end rot is most often caused by watering practicesвyour own or Mother Nature s. In a typical situation, the soil is allowed to dry out completely, and then the gardener over-compensates by watering heavily when the plant

 why do pregnant women get so gassy

why do pregnant women get so gassy

Gas can cause excruciating abdominal pain. It may stay in one area or travel throughout your belly, back, and chest. According to the, women experience more gas during pregnancy due to increased progesterone. Progesterone causes intestinal muscles to relax and extends the time it takes food to get through the intestines. Food remains in the colon longer, which allows more gas to develop. As your pregnancy progresses, your enlarging uterus puts extra pressure on your organs, which can slow digestion further and allow gas to build up. If abdominal pain is caused by gas, it should respond to lifestyle changes. Try eating several small meals throughout the day and drink lots of water. may also help aid digestion. Identify foods that and avoid them. Fried and greasy foods, as well as beans

 why do we need to preserve our culture

why do we need to preserve our culture

Share your culture's art and technology. Each culture has its own clothing, music, visual art, storytelling traditions, and many more unique characteristics. Other members of your culture will be overjoyed to teach or talk about their hobbies, their jobs, their crafts, and what they do for fun. This includes traditional artwork you would find in a museum, but material culture goes far beyond that. Even a kitchen spoon or a piece of software is a cultural artifact. People with less sophisticated technology are often considered ignorant or less intelligent. This is completely wrong. Culture passes on tools adapted to a particular environment, and every tool has generations of thinking behind it. is one of the oldest cultural practices there is, and it still takes great skill and knowledge.

 why do people turn red when they drink

why do people turn red when they drink

Words by Jadie Troy-Pryde When it comes to our drinking habits, we would say weвre pretty clued up. Weвre well aware that men and womenвs ideas about are largely different, and although alcohol has no real medicinal value, you can. But have you ever wondered why some people turn red when they drink alcohol? Thereвs proof that at all (so no more blaming drunk you for any outrageous behaviour), but we do know it affects us all differently. You may have noticed that a friend of yours tends to get a bit flushed after a glass or two of wine в so why doesnвt it happen to everybody? Why does it only happen to a handful of us? ...

 you know how i feel x factor

you know how i feel x factor

2012: The X Factor In 2012, Sonenclar auditioned for the of with the song " " by and (famously covered by among others). Sonenclar received a standing ovation from all four judges ( commented "You may be 13, but your soul is old! "; awarded her "4,833 yes'"), and she advanced to the next round. After her successful initial audition, she advanced through the first day of X Factor's "bootcamp," where she sang " " with. Of the 120 contestants who auditioned at bootcamp that day, she was among the sixty or so asked to continue on. At the end of bootcamp, she was chosen to be one of the six contestants in the "teens" category who were invited to perform at the "judges' houses" stage of the competition. She performed the song " " for the "teens" category mentor, and Spears' guest judge. Both

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