Büchner flask is a thick-walled Erlenmeyer flask with a short glass tube and hose barb protruding about an inch from its neck.
The short tube and hose barb effectively act as an adapter over which the end of a thick-walled flexible hose (tubing) can be fitted to form a connection to the flask.
The other end of the hose can be connected to source of vacuum such as an aspirator, vacuum pump, or house vacuum.
Crystal is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions.
In addition, macroscopic single crystals are usually identifiable by their geometrical shape, consisting of flat faces with specific, characteristic orientations.
The process of crystal formation via mechanisms of crystal growth is called crystallization or solidification.
Examples of large crystals include snowflakes, diamonds, and table salt.
Types of Chemical Bonds
Ionic bonding is a type of chemical bonding that involves the electrostatic attraction between oppositely charged ions, or between two atoms with sharply different electronegativities, and is the primary interaction occurring in ionic compounds. It is one of the main types of bonding along with covalent bonding and metallic bonding.
Covalent bond is a chemical bond that involves the sharing of electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs, and the stable balance of attractive and repulsive forces between atoms, when they share electrons, is known as covalent bonding.
Metallic bonding is a type of chemical bonding that arises from the electrostatic attractive force between conduction electrons (in the form of an electron cloud of delocalized electrons) and positively charged metal ions. It may be described as the sharing of free electrons among a structure of positively charged ions (cations).
Pure gas may be made up of individual atoms (e.g. a noble gas like neon), elemental molecules made from one type of atom (e.g. oxygen), or compound molecules made from a variety of atoms (e.g. carbon dioxide).
A gas mixture, such as air, contains a variety of pure gases.
What distinguishes a gas from liquids and solids is the vast separation of the individual gas particles.
Thermite reaction is an exothermic oxidation-reduction reaction similar to the ignition of black powder.
The reaction requires a metal oxide and fuel. This heat, combined with the aluminum and iron oxide, produces aluminum oxide, elemental iron, and a large amount of heat and light.
The colors in fireworks
The colors in fireworks come from a simple source: pure chemistry.
They’re created by the use of metal salts. These salts are different from table salt, and in chemistry ‘salt’ refers to any compound that contains metal and non-metal atoms.
Some of these compounds produce intense colors when they are burned, which makes them ideal for fireworks.
Others, like potassium nitrate, sulfur and charcoal are often used to help the fireworks burn.
Chemical reaction is a process that leads to the chemical transformation of one set of chemical substances to another.
Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and breaking of chemical bonds between atoms, with no change to the nuclei (no change to the elements present), and can often be described by a chemical equation.
Liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure.
A liquid is made up of tiny vibrating particles of matter, such as atoms, held together by intermolecular bonds.
Like a gas, a liquid is able to flow and take the shape of a container. Most liquids resist compression, although others can be compressed.
Unlike a gas, a liquid does not disperse to fill every space of a container, and maintains a fairly constant density.
Element is a pure substance consisting only of atoms that all have the same numbers of protons in their nuclei. Unlike chemical compounds, chemical elements cannot be broken down into simpler substances by any means.
The number of protons in the nucleus is the defining property of an element, and is referred to as its atomic number – all atoms with the same atomic number are atoms of the same element.
All of the baryonic matter of the universe is composed of chemical elements.