Matter

Matter
Element Compound Mixtures States of Matter

Definition

Matter is everything around you. Matter is anything made of atoms and molecules. Matter is anything that has a mass. Matter is also related to light and electromagnetic radiation. Even though matter can be found all over the universe, you usually find it in just a few forms. As of 1995, scientists have identified five states of matter. They may discover one more Matter has mass and occupies space. All matter is composed of basic elements that cannot be broken down to substances with different chemical or physical properties.

Matter is classified into two major categories:

Pure Sustances & Impure Substances(Mixtures).

Pure Substances is further classified into Elements & Compound. Impure Substances is further classified into Homogeneous & Heterogeneous Mixtures.

























Properties Of Matter

There are four different properties of matter. They are mass, volume, density and weight,.

Mass

The most important one is Mass. Mass is the amount of matter in an
object and it never changes unless matter is taken out of the object.
Mass also has a direct relationship with inertia. Inertia is the resistance of motion of an object. If an object has a greater mass, then it has a greater inertia.

Volume

Volume is another general property of matter. Anything that takes up space has volume. In fact, volume is the amount of space an object takes up. You can find a straight-edged object's volume by measuring the Length x Width x Height. For irregular shaped objects, you'd probably want to use a graduated cylinder. Litres and millilitres are used to measure the volume of liquids, while cubic centimeters are used to measure solids.

Density

The third general property of matter is Density. Density is very important because it enables you to compare different objects. For instance, water has a density of 1 gram/cc and wood is 0.8 grams/cc. Therefore, wood will float in water because it's density is less than that of water. The equation for density is Density=Mass/Volume. Also, if you split an object in half, it will still have the exact same density.

Weight

Weight is the fourth general property of matter. It is defined as the measure of force of attraction between objects due to gravity. Gravity is what keeps you and me on the ground. In fact, gravity exists between you and your computer. You are attracted to it by gravity. You don't feel the attraction because the computer's mass is so small. The earth, on the other hand has a very large mass. That's why you are attracted to the ground. Weight, unlike mass, changes with location. The farther you are from the center of the Earth, the less you weigh. The metric unit for weight is the Newton, even though in America the most common unit is the pound. The equation for weight is Weight=Mass x Acceleration due to gravity(a).


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Elements

It is defined as a substance that cannot be further reduced to simpler substances by ordinary processes. Elements are made up of particles/atoms of only one kind.

For example: Hydrogen and oxygen There are 114 elements known. Out of these 92 of them occur in nature.

Classification of Elements


Elements can be further divided into Metals and Non-metals.

Metals

They are generally solids with characteristics such as hardness, malleability, ductility high tensile strength, lustre and ability to conduct heat and electricity.

For example: Copper, iron, zinc etc.

Physical Properties of Elements


Physical State
Metals are solids at room temperature with the exception of mercury and gallium, which are liquids at room temperature.

Lustre
Metals have the quality of reflecting light from its surface and can be polished e.g., gold, silver and copper.

Malleability
Metals have the ability to withstand hammering and can be made into thin sheets known as foils.

Ductility
Metals can be drawn into wires. 100 gm of silver can be drawn into a thin wire about 200 meters long.

Hardness
All metals are hard except sodium and potassium, which are soft and can be cut with a knife.

Valency

Metals have 1 to 3 electrons in the outermost shell of their atoms.

Conduction
Metals are good conductors because they have free electrons. Silver and copper are the two best conductors of heat and electricity. Lead is the poorest conductor of heat. Bismuth, mercury and iron are also poor conductors

Density
Metals have high density and are very heavy. Iridium and osmium have the highest densities where as lithium has the lowest density.

Melting and Boiling Point
Metals have high melting and boiling point. Tungsten has the highest melting point where as silver has low boiling point. Sodium and potassium have low melting points.

Electropositive Character
Metals are elements that have a tendency to lose electrons and form cations. They normally do not accept electrons.

To Summarize:
Metals are electropositive in nature, lustrous, malleable, ductile, good conductors of heat and electricity and generally form basic or amphoteric oxides with oxygen.

Non-Metals


They are generally non-lustrous, brittle, poor conductors of heat and electricity.

For example: Sulphur, phosphorus, nitrogen etc

Physical Properties of Non-metals


Physical State
Most of the non-metals exist in two of the three states of matter at room temperature: Gases (oxygen) and Solids (carbon). These have no metallic lustre, and do not reflect light.

Nature

Non-metals are very brittle, and cannot be rolled into wires or pounded into sheets.

Conduction
They are poor conductors of heat and electricity.

Electronegative Character
Non-metals have a tendency to gain or share electrons with other atoms. They are electronegative in character.

Reactivity They generally form acidic or neutral oxides with oxygen.

Comparative Property of Metals & Non-Metals




































Position of Metallic and Non-Metallic Elements in the Periodic Table

Metals: Metals occur on the left hand side of the Periodic Table.

Non-metals: Non-metals occur on the right hand side of the Periodic Table.

Semi-metals(metalloids): Semi-metals with properties in between metals and non-metals occur between these two groups. (B, Si, Ge, As, Sb, Te).














Metalloids


These elements have characteristics common to metals and non-metals.

For example: Arsenic, tin, bismuth etc.


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Compound


There are three states- Solids, Liquids, and Gases.


Solids

Solids have the lowest potential energy of the three states. The particles in a solid are strongly attracted to one another because the particles are held in a fairly rigid arrangement; the solid keeps its shape. The fact that solids are practically incompressible suggests that their particles are very closely packed. They are not free to move from one point to another in the solid. However, they do vibrate in their positions and this vibration is a form of kinetic energy. If a solid is heated, its particles begin to vibrate more strongly. Eventually most solids reach a point at which their particles overcome the strong attractive forces, and break free from their fixed positions to become a liquid.

 

Liquids

The particles of a liquid are held together by weak attractive forces. The fact that liquids are slightly compressible indicates that there are small spaces between the particles. The particles tend to remain together but are free to slide around each other and move considerable distances. Liquids take the shape of the container they are held in. Such movement from one point to another is called translation. At the same time, the liquid particles are also vibrating as are the solid particles. When heated the particles translate and vibrate more rapidly, until they overcome the weak attractive forces holding them together and become a gas.


Gases

A gas expands to fill the container it is in. This suggests that the attractive forces acting between its particles are very small or nonexistent. A gas is also easily compressed, indicating that particles are widely separated. The particles vibrate and translate freely. Since energy has been provided to break the attractive forces of both the solid and the liquid phases, gases have the highest potential energy of the three states of matter.






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