Using english to calculate stoichiometry

                         Clasification of metter 

Classification of matter

Matter can be classified into two categories: pure substances and mixtures. This classification is based on the internal composition of that matter. Using composition to describe matter is better than using its state, because the internal makeup makes matter unique, and not its phase or state. Example, water (H2O) can be vapor, solid or the usual liquid. This means that scientifically, it is not correct to say water is a liquid, even though we all know that water is usually a liquid.



In a similar vein, classifying matter only according to its color, size, or weight is not enough because two identical objects can be of the same color, but their internal makeup may be different. Example, a glass of water from a lake may look and weigh the same as another identical glass of water from another lake — but it does not mean they are the same. They are all water, but the chemical compositions may be very different.

So, in this lesson, we shall see more about the classifications and the various ways and forms in which matter is made up, mixed up and if they can be separated at all. 


Elements


Each in an element will be given a symbol in accordance with the rules of writing in the international. The following are the rules of writing in an element.A. For the symbol of the element that consists of only one letter, the writing isUsing capital letters.Examples such as:

    Carbon denoted C.
    Hydrogen element denoted H.
    The oxygen element is denoted 0.B. For the element symbol consisting of two letters, the first letter writingUsing capital letters and the second letter by using lowercase letters.Examples such as:

    The element of Sodium is denoted Na.
    Calcium element is denoted Ca.To easily learn and observe an element, a table called the periodic table of elements is created. Periodic table of this element is a table that describes the elements that exist in the chemistry made in the form of tables. The elements are arranged on the basis of their chemical electron structure which varies irregularly throughout the table. Each element is listed by atomic number and its element symbol. In the periodic table of elements, elements are grouped into classes and periods based on similarity of properties. Groups in the periodic table are arranged vertically (from top to bottom), while the element period is arranged horizontally (from left to right).

Some atoms can also join up with other atoms of the same element. When two or more atoms join up, they form a molecule. Oxygen, (O2) is a molecule because it has two atoms joined together. An oxygen molecule looks like those in the diagram above. 

Elements are pure in nature. They may vary in size as long as the atoms joining to make its molecules are the same. As soon as a different atom joins (bonds), it ceases to be an element — it is now a  compond.

Sometimes, atoms can join up with other atoms of other elements in chemical bonds. When that happens, a compound is formed. This means that a molecule can be made up of two atoms of the same element, OR can be made up more atoms of different elements.


Compounds 

Definition of the Compound is a composite consisting of two or more elements that combine chemically with a particular ratio in each molecule. The compound can be written in a chemical formula. The chemical formula of a compound can be a molecular formula and an empirical formula. There is no formula molecule and formula empires it pa ???Kalua The molecular formula is a molecule present in a chemical formula that states a type and number of atoms that can compose a substance. While the empirical formula is a chemical formula which expresses the smallest ratio or the sum of the compounding atoms. An example such as n-hexane has a formula whose molecule consists of CH3CH2CH2CH2CH2CH3, which states that this compound must have a straight chain structure of each of 6 carbon atoms, and 14 hydrogen atoms. With the formula of the molecule it can be concluded that the chemical formula of hexane is C6H14, while the empirical formula is C3H7 which shows the C: H ratio of 3: 7.1. The properties present in the compoundThe compound turns out to have its own properties, the following are the properties of the compound:A. The compound may be formed by a process of a chemical reactionB. The constituent components present in a compound must have a certain ratio of a fixed nature.(Proust law)C. The compound will not be separated withIts constituent components back by physical reactions.D. The compound can be categorized as a single substance compound.E. Have different propertiesWith the constituent elements comparing two hydrogensAnd one oxygen
 
A compound is a substance made from two or more elements that have reacted chemically with each other. The elements in the compound can NOT be separated by physical means.

Water is a compound. It is written as (H2O). This means it is a chemical bond of two elements—Hydrogen and Oxygen. It is written as (H2O) because there are two atoms of Hydrogen, making it a hydrogen molecule, bonding with one atom of Oxygen.

Note that there are so many ways that molecules of elements join together, forming millions of compounds. All compounds are molecules but not all molecules are compounds.

It is also important to note that compounds do not necessarily look like the elements that formed it. Compounds are usually a result of a chemical reaction or bond, which means that they are entirely new materials. For example, Hydrogen and Oxygen elements are both gases, but after bonding chemically, they form water, which is liquid at room temperature.

Another good example is Iron sulfide, a compound formed from bonding two elements— iron and sulfur.



Iron is silvery grey and can be attracted to a magnet. Sulfur is yellow and cannot be attracted to a magnet. In this chemical bond, sulfur and iron are mixed up and heated. The result is a compound, iron sulfide, which is black and not attracted to magnets. The above is a diagram of the compound.

 
Substances

A substance is simply matter with definite chemical composition and distinct properties. It is matter that is characterized by a constant composition in terms of its molecules, formulae and atoms, as well as physical properties such as density, refractive index, electric conductivity, melting point, and so on.

A substance can be an element or a compound but NOT a mixture. It can also be matter that exists in its pure form, usually called a pure substance. A few examples of substances include Water (H2O), Hydrogen (H2) and Neon (Ne).

Other examples of chemical substances commonly seen in pure form are salt (sodium chloride), diamond (carbon) and gold. 

Substances cannot be separated into components by physical separation techniques. Some substances, like water, can be broken down into elements by a chemical reaction (to break chemical bonds). A substance can be solid, liquid, gas, or plasma.

Mixture 


The mixture is a combination of several substances with their non-fixed ratio and without a chemical reaction. Indigenous properties in a mixing substance that exist that can still be distinguished from each other. A mixture is formed of little bits of one or more substances mixed together. Usually, the parts can be separated from each other by physical means, because it does not involve any chemical reactions or bonds. 

Mixed Example
Mixture can occur between
1) solids with solids, such as sugar with coffee;
2) solids with liquids, eg sugar with water;
3) solids with gases, for example airborne dust;
4) liquids with liquids, such as alcohols with water;
5) liquids with gases, such as water in the air during rain;
6) gas with gas, for example air which is a mixture of various gases.
 
Types of Mixtures 

A mixture can involve two or more substances of the same phase or different phases. For example you can mix water and sand (liquid and solid), sugar and salt (solid and solid), water and oil (liquid and liquid) or nitrogen and oxygen (gas and gas). Clearly, mixtures can vary a lot and can be homogeneous or heterogeneous.

Homogeneous mixture:

Mixtures involve mixing substances, so let us first be clear what a homogenous substance is. When a sample of matter has the same composition throughout, we call that substance a homogeneous substance. A cup of water will have the same chemical composition throughout (H2O). That makes it a homogeneous substance. A piece of gold will also have the same chemical composition, making it a homogenous substance.  
 Characteristics Homogeneous solution
The homogeneous mixture (solution) has characteristics, ie

1) the size of molecular sized mixed substance substances;

2) the mixed matter particles will be uniformly mixed;

3) the mixture will not settle if ignored (not stirred);

4) clear and translucent.

Homogeneous Mixtures behave in a similar way — the substance formed appear to have the same chemical composition. Alloys and Solutions are Homogeneous mixtures. The following is the nature of the solution.
A. In the solution It consists of two or more substances each of which the constituent particles are dispersed and evenly distributed throughout the solution.
B. In solution The particle size of the solution is less than 10 nm.
C. Each solvent constituent particles spread evenly throughout the solution.

Heterogeneous Mixture

A mixture can also result in two or more phases clearly separated by boundaries. Very often, the separation can be clearly seen by the eye. A heterogeneous mixture is one that does not have uniform properties and composition. Take a look at a bowl of cereal with nuts. A spoon full will surely have a different number of nuts than a second spoonful taken at random. Another example—take some sea-sand into your palms. 

 Features Heterogeneous mixtures
Heterogeneous mixtures have characteristics, ie

1) the size of the mixed particles larger than the molecule;

2) mixing the particles unevenly;

3) the solution will precipitate (the solvent and solute particles separated) if ignored;

Look at it closely and you will notice that some sand particles are bigger than others, and the colors of some particles may be different too. They are NOT uniform in any way!
Heterogeneous mixtures include colloids, emulsions or suspensions.