Matters can be found in daily life around you. You can use matters fulfil you needs. When hungry you need food, when thirsty you need water. You also need dirt, rocks or sand to building house.
Soil, rocks, paraffin, gasoline, wood, cloth, and your own body and also various materials you see everyday are matter. The various forms of matters have one similarity, which is having mass and occupying space. So, matters are everything which has mass and volume (occupying space).
All matters in nature will experience change, nothing is eternal. Matter will experience change in mass, volume and form, even change to another matter.For example, water evaporates , wood burns into ashes, corpse change into dirt, and fruits root. Therefore, the only thing that eternal in only the one and only God. Matter is classified into 2 large groups, which are pure substance or single substance and mixture.
A. SINGLE SUBSTANCE
Single substance is often called just as substance. Substance is a matter with the same properties and organization in all parts of it. Substance are classified into elements and compounds.
1. Elements
Element is a single substance which chemically can't be disassembled into other simpler substance. Element are basic materials or the universe, each has unique atomic structure which determines its chemical properties. Ninety two elements have been found on earth. 80% of them are classified into metals which properties are conductor of heat, can be molded or extended and shiny. The rest are are non-metal substance which have more varying properties, which includes gases, liquid and solid. 90.5% of the mass of earth's crust are made only from eight elements, which are, sorted from the most abundant, oxygen, silicon, aluminium, iron, calcium, sodium, potassium and magnesium. All other elements are only 1% or less. Most element in nature are attached to other elements, forming compounds and not free state, for example gold and oxygen.
a. Name and Symbol of Elements
In old times, chemist of medieval times have named chemical elements and used symbol to write them. An English scientist, John Dalton (1766-1844), made himself symbols of element with circle and a certain figure inside the circle for each element. And the symbol of compound was made by combining several symbols of its basic elements. Dalton's element symbol have weakness is impractical for writing compounds.
Old Elements Symbol |
Dalton's Element Symbol |
The convention of writing element symbols is as follows.
1). Symbol of elements are formed from abbreviation of their names, which generally in Latin.
2). An element is symbolized by using capital letter of the first letter of the name in Latin (Scientific name).
example:
Elements
|
Scientific
Name
|
Element
Symbol
|
Oxygen
|
Oxygen
|
O
|
Hydrogen
|
Hydrogen
|
H
|
Carbon
|
Carbon
|
C
|
3). An element is symbolizes with 2 letter if its name has the same first letter with another element. The first letter which is the first of its name is written in capital letter and the second latter is taken from the next letter of its name and written in small letter.
example:
Elements
|
Scientific
Name
|
Element
Symbol
|
Calcium
|
Calcium
|
Ca
|
Chlorine
|
Chlorine
|
Cl
|
Cadmium
|
Cadmium
|
Cd
|
The following are known elements and their symbols.
b. Chemical Formula
In chemistry, chemical formulas are classified into 2 based on the number of their atoms. Both formulas include element chemical formula chemical formula.
1). Element Chemical Formula
Element with monoatomic atom (one atom) have element chemical formula similiar to their element symbol.
Example : Carbon = C
Silver = Ag
2). Compound Chemical Formula
Compounds which are made of particles in the form of molecules have chemical formula which is called molecular formula. Molecular formulas show the number of atoms of each element which form the compound molecule. therefore, molecular formula is the symbol of a compound.
- Element which form a molecule by attaching two similar atoms (diatomic).
example : Hydrogen = H2 ; Flourine = F2 ; Iodine = I2
Oxygen = O2 ; Nitrogen = N2 ;
- Element which attach more than 2 similar atoms (atomic).
example : Phosphor = P4 (tetra atomic) ; Sulphur 58 (octet atomic)
- Compound which are formed from more than 2 different atoms.
example : Water Compound = H20
Glucose compound = C6H12O6
2. Compound
Generally, element in nature aren't found in free state. but attached to each other in the form of compounds. A compound has at least 2 elements. Therefore, a compound in an attachment of 2 or more elements with a certain ratio. A compound has different chemical properties from the elements which formed it. Sodium or chlorine in the form of elements is a dangerous element. But, in the form of a compound, sodium chlorine is an important compound to the body of a life form.
a. Composition of a Compound
Compound are single substance, but can be disassembled into its elements using common chemical reactions. For example, water can be disassembled into hydrogen and oxygen elements through electrolysis reaction.
c. Compounds and Their Use
Up to this day there are more than 10 millions of compounds known and the number is still growing. Compounds exist in nature and also made in laboratories by way of synthesis. Example :
1. Acetic acid (CH3COOH) = Vinegar
2. Benzoic acid (C6H5COOH) = food preservative
3. Calcium carbonate (CaCO3) = Building material
4. Sulphuric acid (HSO) = acid for car batteries
5. Hydrochloric acid (HCl) = floor cleaner
6. Sodium Chloride (NaCl) = common salt
7. Ascorbic acid (C6H8O6) = Vitamin C
B. MIXTURES
Everything in nature is made of chemical substance, including your body. Several objects consist of one subject, but most foods are mixture. Mixture of coffee and hot water form solution which can still separated. Heated coffee mixture will result in pure water in the form of water vapor and left off coffee powder. A mixture of salt and sand is still shown the form of each substance's grains. So, mixture may be solutions, solid or gases like the air around us. The components which made a mixture vary. Sometimes a mixture consist of very soft components so that to needs the help of a microscope to differentiate them.
various objects in form of mixtures |
The gold in commerce is an alloy, expect 24 carat gold. Gold accessories sold are 18 carat, 20 carat or 22 carat. To strengthen gold, the mixture often which used is copper. But, to have a more interesting appearance, beside copper, the gold is also mixed with silver resulted gold in white color or white gold. Mixtures can be classified into homogenous mixtures and heterogeneous mixtures.
1. Homogenous Mixture
vinegar mixed with water is an example of solution |
2. Heterogeneous Mixture
mixture between sugar and chocolate powder |
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