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Column chromatography in chemistry is a method used to purify individual chemical compounds from mixtures of compounds. It is often used for preparative applications on scales from micrograms up to kilograms. The main advantage of column chromatography is the relatively low cost and disposability of the stationary phase used in the process. The latter prevents cross-contamination and stationary phase degradation due to recycling.
The classical preparative chromatography column, is a glass tube with a diameter from 5 mm to 50 mm and a height of 5 cm to 1 m with a tap and some kind of a filter at the bottom. Two methods are generally used to prepare a column: the dry method, and the wet method.
⁕For the dry method, the column is first filled with dry stationary phase powder, followed by the addition of mobile phase, which is flushed through the column until it is completely wet, and from this point is never allowed to run dry.
⁕For the wet method, a slurry is prepared of the eluent with the stationary phase powder and then carefully poured into the column. Care must be taken to avoid air bubbles. A solution of the organic material is pipetted on top of the stationary phase. This layer is usually topped with a small layer of sand or with cotton or glass wool to protect the shape of the organic layer from the velocity of newly added eluent. Eluent is slowly passed through the column to advance the organic material. Often a spherical eluent reservoir or an eluent-filled and stoppered separating funnel is put on top of the column.

Cracidae is a family of birds common in the South American tropical forests, also known as chachalacas, guans, and curassows. They are large birds with long tails and bills, known for being very vocal. They are predominantly herbivorous, feeding on fruits, leaves, and flowers, with some species also consuming small animals. Most species are arboreal and spend most of their time in treetops. They play a crucial role in forest regeneration as they distribute seeds through their droppings.

Silverrod is a common name for a species of flowering plant known as Solidago bicolor. It is native to eastern North America and is also known for its silver-white flowers, unlike most other species in its genus which have yellow flowers.

Pharomacrus mocino, also known as the Resplendent Quetzal, is a bird species found in the humid highland forests in Central America. It is a member of the Trogon family and is known for its colorful plumage and long tail feathers. It is also considered as one of the most beautiful and remarkable birds in the western hemisphere. The Resplendent Quetzal plays an important role in various types of Mesoamerican myths and as a symbol in both Mayan and Aztec cultures.

The Philippine peso, often denoted by the symbol ₱, is the official currency of the Philippines. It is subdivided into 100 centavos or sentimos in Filipino. The Central Bank of the Philippines, known as Bangko Sentral ng Pilipinas, is in charge of issuing, handling, and regulating the Philippine peso. Its exchange rate with other currencies varies and is determined by the foreign exchange market.

Nameko is a type of small, amber-hued edible mushroom native to Japan. They are known for their slightly nutty flavor, rich texture, and the gelatinous layer that surrounds them when cooked, which is often used to thicken soups. Nameko mushrooms are commonly used in Japanese cuisine, particularly in miso soup.

Klinefelter syndrome is a genetic condition that affects males, typically caused by an extra X chromosome. This can lead to a range of physical and cognitive symptoms, including underdeveloped genitals, infertiltiy, less body hair, taller than average height, learning disabilities, and in some cases, breast growth. The syndrome is usually diagnosed through genetic testing.