Examples of Coordination Covalent Bonds: BF3NH3
5B = 1s2 2s2 2p1
9F = 1s2 2s2 2p5
7N = 1s2 2s2 2p3
Example of the BF3NH3 Coordination Agreement
Properties of Covalent Compounds:
Boiling point
In general, covalent compounds have a low boiling point (average below 200 0C). For example Water, H2O is a covalent compound. The covalent bonds that bind between hydrogen atoms and oxygen atoms in water molecules are quite strong, while the binding force between water molecules is quite weak. This condition causes the water in the liquid phase (form) will easily turn into water vapor when heated to around 100 0C, but at this temperature the covalent bonds in the H2O molecule do not break.
Boiling point
Volatility (ability to evaporate)
Most covalent compounds are volatile liquids and gases. The molecules in covalent compounds which have volatile properties often produce a characteristic odor. Perfume and scent ingredients are covalent compounds, for example from volatile covalent compounds
Volatility
Solubility
In general, covalent compounds can not dissolve in water, but easily dissolve in organic solvents. Organic solvents are carbon compounds, for example gasoline, kerosene, alcohol, and acetone. But there are some covalent compounds that can dissolve in water because they react with water (hydration) and form ions. For example, sulfuric acid when dissolved in water will form hydrogen ions and sulfate ions. Covalent compounds that can dissolve in water hereinafter referred to as polar covalent compounds, while covalent compounds that are not soluble in water are subsequently referred to as non-polar covalent compounds.
Solubility
Electrical conductivity
In general, covalent compounds in various forms cannot conduct electric current or are non-electrolyte, except polar covalent compounds. This is due to polar covalent compounds containing ions when dissolved in water and these compounds include weak electrolyte compounds. Here follows a picture of the difference between non-electrolyte compounds, weak electrolytes and strong electrolytes.
Thermochemistry is the science of changing heat (heat) of a substance that involves chemical and physical processes. Thermochemistry, which is part of Thermodynamics, discusses the energy changes that accompany a chemical reaction that is manifested as a reaction heat. The constituent particles are always in constant motion, so the substances have kinetic energy. The average kinetic energy of an object is directly proportional to its absolute temperature (0K).
this means that if an object is hot, the atoms of the molecules making up the object move fast, so the kinetic energy of the object is large. The potential energy of a substance arises from the attractive and repulsive forces between the constituent particles of matter. One form of energy that is commonly found is heat energy.
Heat is a form of energy that can be exchanged between the system and the environment. Reaction heat is a change in energy in a chemical reaction in the form of heat. In general, to detect the heat that is owned by an object by measuring the temperature of the object. If the temperature is high, the heat contained by objects is very large, and vice versa if the temperature is low, the heat contained is small.
A tool to measure the heat of a reaction from a chemical reaction is a calorimeter. A calorimeter that uses the technique of mixing two substances in a container, is generally used to determine the specific heat of a substance. There are two types of calorimeter namely fixed volume calorimeter and fixed pressure calorimeter.