Differences Between Citric and Ascorbic Acid (Vitamin C)

Chemistry
Two familiar acids, found in citrus fruit, are citric acid and ascorbic acid (Vitamin C). But what are these acids and how are they different? First, consider the structure of these two food acids. Examine the Image The two acids look different, yet somehow they look similar. Each has a ring, or what almost passes as a ring, and each contains an abundance of oxygen atoms (O). There are three carboxylic acid groups –C=O(OH) are found in the citric acid molecule. On the other hand, ascorbic acid contains no carboxylic acid groups. Yet it, too, is acidic, about as acidic as vinegar. Citric acid with its carboxylic acid groups is the more acidic acid and so is more sour to the taste. But why is ascorbic acid acidic if it…
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What is a Hydronium Ion?

Chemistry
What is a hydronium ion? Water... Is there a more important or abundant liquid on the face of the earth? It possesses an amazing number of properties. It is essential to our very existence. Water is one of an extremely small number of substances (liquid ammonia is another) that expands and becomes lighter on freezing. Ice floats and forms an insulating, protective crust over underlying water. If ice sank rather and didn't float instead, the ponds and lakes of earth would completely freeze. All living things would die. Structure & Electrical Properties of Water Water's chemical formula is H2O. Occasionally it is written HOH or H–O–H. This way of writing the structure is convenient as long as one is aware of the shortcomings. Water is not a linear molecule. It…
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Factors that Complicate Atomic Mass Determination

Physics
[caption id="attachment_8319" align="alignright" width="440"] Nucleus - CC-SA-3.0 by Marekich[/caption] Modern chemistry depends a good deal upon accurately knowing the atomic mass of each of the elements. What factors complicate determining those values? Each of the approximately 90 different natural-occurring elements possesses a nucleus or central core of protons and neutrons, in addition to electrons that orbit around the nucleus. It is important to the chemist or physicist to know the total mass of each element. Can correct values be obtained simply by summing the weight of individual particles in an atom? After all, each of these particles has a precisely known mass. The answer is, No! Such calculations disagree with experimental measurement. An example illustrates the point. Consider Helium-3 An atom of helium-3 has two protons, one neutron, and two…
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