Carbonic acid

Carbonic acid is a chemical compound with the chemical formula H₂CO₃ (equivalently OC(OH)₂). It is also a name sometimes given to solutions of carbon dioxide in water (carbonated water), because such solutions contain small amounts of H₂CO₃. In physiology, carbonic acid is described as volatile acid or respiratory acid, because it is the only acid excreted as a gas by the lungs.

Carbonic acid, which is a weak acid, forms two kinds of salts, the carbonates and the bicarbonates. In geology, carbonic acid causes limestone to dissolve producing calcium bicarbonate which leads to many limestone features such as stalactites and stalagmites.

The long-held belief that carbonic acid could not exist as a pure compound has reportedly been recently disproved by the preparation of the pure substance in both solid and gas form by University of Innsbruck researchers.

Chemical equilibrium

When carbon dioxide dissolves in water it exists in chemical equilibrium producing carbonic acid:

The hydration equilibrium constant at 25 °C is called K_h, which in the case of carbonic acid is [H₂CO₃]/[CO₂] ≈ 1.7×10⁻³ in pure water and ≈ 1.2×10⁻³ in seawater. Hence, the majority of the carbon dioxide is not converted into carbonic acid, remaining as CO₂ molecules. In the absence of a catalyst, the equilibrium is reached quite slowly. The rate constants are 0.039 s⁻¹ for the forward reaction (CO₂ + H₂O → H₂CO₃) and 23 s⁻¹ for the reverse reaction (H₂CO₃ → CO₂ + H₂O). Carbonic acid is used in the making of soft drinks, inexpensive and artificially carbonated sparkling wines, and other bubbly drinks. The addition of two molecules of water to CO₂ would give orthocarbonic acid, C(OH)₄, which exists only in minute amounts in aqueous solution.

Volatility (finance)

In finance, volatility is the degree of variation of a trading price series over time as measured by the standard deviation of returns.

Historic volatility is derived from time series of past market prices. An implied volatility is derived from the market price of a market traded derivative (in particular an option). The symbol σ is used for volatility, and corresponds to standard deviation, which should not be confused with the similarly named variance, which is instead the square, σ².

Volatility terminology

Volatility as described here refers to the actual current volatility of a financial instrument for a specified period (for example 30 days or 90 days). It is the volatility of a financial instrument based on historical prices over the specified period with the last observation the most recent price. This phrase is used particularly when it is wished to distinguish between the actual current volatility of an instrument.

Volatile (A Hero A Fake album)

Volatile is the debut album by American metalcore band A Hero A Fake, released on October 28, 2008 through Victory Records. A music video for the album's single, I Know I, was produced by Scott Hansen and premiered on MTV2 on February 21, 2009.

Track listing

All lyrics written by Justin Brown, all music composed by A Hero A Fake.

Personnel

† filed for name change to Alex Avigliano

References

Customer

A customer (sometimes known as a client, buyer, or purchaser) is the recipient of a Good or a service, or a product, or an idea, obtained from a seller, vendor, or supplier via a financial transaction or exchange for money or some other valuable consideration. Etymologically, a client is someone merely inclined to do business, whereas a purchaser procures goods or services on occasion but a customer customarily or habitually engages in transactions. This distinction is merely historic. Today customers are generally categorized into two types:

A customer may or may not also be a consumer, but the two notions are distinct, even though the terms are commonly confused. A customer purchases goods; a consumer uses them. An ultimate customer may be a consumer as well, but just as equally may have purchased items for someone else to consume. An intermediate customer is not a consumer at all. The situation is somewhat complicated in that ultimate customers of so-called industrial goods and services (who are entities such as government bodies, manufacturers, and educational and medical institutions) either themselves use up the goods and services that they buy, or incorporate them into other finished products, and so are technically consumers, too. However, they are rarely called that, but are rather called industrial customers or business-to-business customers. Similarly, customers who buy services rather than goods are rarely called consumers.

Financial market

A financial market is a market in which people trade financial securities, commodities, and other fungible items of value at low transaction costs and at prices that reflect supply and demand. Securities include stocks and bonds, and commodities include precious metals or agricultural products.

In economics, typically, the term market means the aggregate of possible buyers and sellers of a certain good or service and the transactions between them.

The term "market" is sometimes used for what are more strictly exchanges, organizations that facilitate the trade in financial securities, e.g., a stock exchange or commodity exchange. This may be a physical location (like the NYSE, BSE, NSE) or an electronic system (like NASDAQ). Much trading of stocks takes place on an exchange; still, corporate actions (merger, spinoff) are outside an exchange, while any two companies or people, for whatever reason, may agree to sell stock from the one to the other without using an exchange.

Trading of currencies and bonds is largely on a bilateral basis, although some bonds trade on a stock exchange, and people are building electronic systems for these as well, similar to stock exchanges.

Market (2003 film)

Market is a 2003 film directed by Jay Prakash and starring Manisha Koirala. The film follows the story of Muskaan Bano (Manisha Koirala) from her life in Indian brothels after being sold there by her Arab husband to her attempts at revenge later in life. The film garnered a decent opening and was a surprise success of the year. It was declared Average at the box office.

Music

References

External links