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Ice melts faster in water than in soda. This is because soda has sodium (salt) in it, and adding sodium makes ice melt more slowly than it will in plain water. In order for ice to melt, the...
Atoms unite to form molecules by means of available electrons. Bonds can form by electron transfer or by electron sharing. Many chemical bonds are intermediate between those two. Elements combine...
Agarose gels and acrylamide gels are used in biotechnology laboratories for a process called electrophoresis, which is used to separate molecules of different sizes. Electrophoresis is used for...
A complex interconnected series of sugar molecules (saccharides) comprise starch molecules. To test for the presence of these polysaccharides (many sugar) structured starches you will need iodine....
Methane exists as a gas and hexane in liquid form at room temperature because intermolecular forces affect the molecules of these substances differently.
Triglycerides are macromolecules called lipids, better known as fats or oils. Triglycerides are named for the monomer components they contain. "Tri" means three, and triglycerides are built from...
Halogen lights operate on the same principle as other incandescent lamps; however, the different chemicals used to make halogen lamps create a brighter, longer-lasting and more efficient light...
The ideal gas equation discussed below in Step 4 is sufficient for calculating the pressure of hydrogen gas under normal circumstances. Above 150 psi (ten times normal atmospheric pressure) and...
Atoms are the elemental building blocks of molecules. Chemistry involves the study of atoms, molecules and their interactions. Chemists use a kind of shorthand notation to write chemical...
The vast applications of electrophoresis are most evident in the health or medical industry, including antibiotic and vaccine analysis. Protein and DNA analysis are also important electrophoresis...
Suppose you have a solution of known substance X but unknown concentration. You want to learn the concentration by fully reacting it with substance Y. Knowing how much of Y was used up tells you...
Atoms and molecules are the basic building blocks of matter. Differentiating molecules from atoms is essential to understanding your physical environment that is based upon chemical reactions.
Ice crystals are magnificent natural water formations. These fascinating structures can be as small as a snowflake or as large as a glacier.
The cells of living organisms are of two basic types; prokaryotic and eukaryotic. The prokaryotic cell, the simpler type, is characteristic of organisms like bacteria and blue-green algae. The...
During a redox reaction, energy is transferred from one molecule to another through the transfer of electrons. When a molecule loses electrons, it is losing energy and said to be oxidized. When it...
When speaking about cell balance, it is common to run into the term "homeostasis." A cell must maintain homeostasis, literally a permanent condition where everything remains the same. For a cell,...
Structurally, epoxy resin consists of two main parts: long polymer chains of bisphenol A and epichlorohydrin molecules, and polyamine molecules that links these polymer chains into a net-like...
A cold soft drink on a hot day can be very refreshing; keeping that soft drink cold on a hot day can be quite challenging. In the past, soft drinks were packaged exclusively in glass bottles....
While pectin is used primarily in making jellies or preserving fruit in other ways when manufactured, in nature the complex compound plays a far more important role. Plants produce it to cement...
While DNA is contained within most cells of living organisms, getting it out and examining it is a complex process. All DNA is made from four different bases, known by their abbreviations A, T, C...
Chemical reactions change molecules into different molecules. They do so by interaction of the outermost electrons of the affected atoms. There are millions of chemical reactions but underlying...
Solids are divided into two categories: crystalline solids and amorphous solids. A crystalline solid has a long-range order that is rigid. Examples include table salt and ice. Amorphous solids...
Chemical reactions change molecules into different molecules. The electrons involved are those in the outer shell of the reacting elements. Therefore, the atomic nucleus is unaffected and the...
Electrophoresis is the process of separating certain large molecules so they can be examined more easily. The word itself is derived from Greek, "electro" referring to the electrical current that...
Chemical reactions change molecules into other molecules. They don't change atomic nuclei, thus, they can't change elements into different elements. Instead, they affect the electrons in the...
Photosynthesis allows plants to convert light into food, removes carbon dioxide from the atmosphere and releases oxygen into the atmosphere. Without plants that perform photosynthesis, the oxygen...
Atoms are the building blocks of matter. These tiny particles, themselves made up of even smaller particles, make up every element in the universe, and each element has atoms that are distinct...
"Molecule movement" exists as a variety of components. The translational movement of molecules as complete units in three-dimensional space is one major component. Other components include...
An atomic clock is an extremely accurate timepiece, far exceeding the capabilities of electronic or mechanical clocks. It employs the stable and predictable vibrations of molecules to maintain its...
Water holds unique properties which makes it "sticky" at the surface. Each individual water molecule has one large oxygen atom and two smaller hydrogen atoms. The hydrogen atoms hold a slightly...
A chemical formula shows the number and types of elements in a compound. It is a representation of a substance using symbols for its constituent elements. Such representations use one or two...
Chemical bonding can be split into two broad categories: those that form molecules and those that don't. Covalent and ionic bonds form molecules. Metallic bonding forms a lattice, but not...
The cell membrane, also called the plasma membrane or plasmalemma, regulates what enters and leaves the cell, and has many proteins embedded within it. Molecules cross the cell membrane by...
The cells in our bodies require certain elemental molecules to function, reproduce and repair themselves. Sometimes these molecules are energy structures such as the ATP molecule that are pulled...
The distinction between organic and inorganic chemistry is not a trivial one. Courses of study in universities throughout the world are structured based on the distinction. And even among those...
Although the process is called cellular respiration (CR), cells do not actually "breathe" as organisms do. Instead, they take in a supply of nutrients that they use for energy, and release...
The atom is mostly empty, with mass concentrated in the proton- and neutron-filled nucleus. Quantum mechanics describes the weird behavior at small scales in which negative is attracted to...
The light-dependent stage of photosynthesis is closely related to the plant's green coloring. As sunlight hits the leaves of the plant, yellow and green light are reflected while red and blue...
Electrophoresis is a "powerful and inexpensive molecular separation technique," as stated by Dr. William H. Heidcamp, in the Cell Biology Laboratory Manual. Various reasons exist for carrying out...
Digestion is the process that turns chunks of food into small sugars, amino acids, fatty acids and nucleotide components. These small molecules are used by all the cells in the body to make new...
When water is heated in a vessel, such as a metal or glass pot, it begins to bubble. This begins before boiling due to one mechanism and continues in different fashion with boiling, due to...
The cell surface membrane is a complex biochemical structure critical to the health and functioning of the cell. Eukaryotic cells---those characteristic of all organisms other than primitive ones...
Lava lamps are lighted tubes filled with a substance the floats and bobs through another liquid. They have been around since the mid 1960s, and have been mesmerizing the public ever since. ...
Hydrogen bonds are attractions resulting from dipole charges between electropositive hydrogen and a strongly electronegative atom (oxygen, nitrogen or fluorine) covalently bonded to it. This may...
Respiration is the process that gets oxygen from the air to the tissues of the body and removes carbon dioxide from the body. Metabolism refers to all the chemical reactions in the body, including...
A chemical formula enumerates the elements in a chemical compound. This is done by assigning special meaning to subscripts and superscripts. Simple examples are H2O for water (where the 2 means...
Cellular respiration is the name for an essential biological process that extracts energy from foods in a usable, chemical form known as adensosine triphosphate, or ATP. Cellular respiration...
It is common knowledge that salt can melt snow and ice. The relationship of salt to other properties is fascinating: The salty oceans freeze at lower temperatures than fresh water; salt added to...
Hydrogen is number one on the charts --- the periodic table of the elements, that is. It is the lightest and most abundant element, making up approximately 90 percent of the universe by weight....
Evaporation is a process that demonstrates two of the three phases of water: liquid and gas. Close at hand, your morning cup of coffee can demonstrate the process of evaporation as a cooling...