Presentation on theme: "THE PERIODIC TABLE 2º ESO NATURAL SCIENCES. oThe periodic table represents all of the known elements arranged in groups according to similar properties."— Presentation transcript:
THE PERIODIC TABLE 2º ESO NATURAL SCIENCES
oThe periodic table represents all of the known elements arranged in groups according to similar properties. oElements are arranged in the table in order of their atomic number. oEach box contains the symbol, for the element, the name of the element and it´s atomic number. oThe atomic number of the element is the number of protons and the number of electrons in the atoms of the element. Introduction…… ¡REMEMBER! The periodic table contains all of the naturally occuring and man-made elements
METALS NON METALS Hydrogen is a Non-Metal
Most Reactive Least Reactive
Alkaline Earth Metals Boron Elements Carbon Elements Nitrogen Elements Oxygen Elements
oHydrogen is the lightest element and can be used as a lifting agent in balloons. oSince Hydrogen gas is highly inflammable, it can be dangerous to use. oThis property and others make Hydrogen suitable for use as a fuel. oThe most common use of Hydrogen is in chemical processes and reactions. Hydrogen (Example 1)
Alkaline Metals Alkaline Metals have the following properties in common: oThey have low melting and boiling points compared to most other metals. oThey are very soft and can be cut easily with a knife. oThey have low densities (lithium, sodium and potassium will float on water) oThey react quickly with water, producing hydroxides and hydrogen gas. oTheir hydroxides and oxides dissolve in water to form alkaline solutions.
Properties oSoft oReacts with air oStored in oil oSilver in colour oMelting point 63.38ºc oBoiling point 759ºc Potassium Alkaline - Expample 2
The Transition Elements The Transition Metals have the following properties in common: oThey form coloured compounds oThey are good conductors of heat and electricity oThey can be hammered or bent into shape easily oThey are less reactive than alkali metals such as sodium oThey are usually hard and tough oThey have high densities oThey have high melting points-but mercury is a liquid at room temperature
Gold Transition Elements – Example 3 Properties oSoft for a metal oCan be polished to a high shine oResistant to corrosion oGood conductor of electricity oGood conductor of heat oMelting point ºc oBoiling point 2856ºc
Halogen Elements The Halogen elements have the following properties in common : oThe halogens have similar properties oThey all have seven electrons in the outer shell. oThey all react very vigorously with alkali metals to form salts. oHalogen means salt giver
Chlorine Halogen Elements – Example 4 Properties oDiscovered in 1774 by Carl Wilhelm Scheele, who mistakenly thought it contained oxygen. oObtained from common salt oMelting point ºC oBoiling point ºC
The Noble Gases The Noble Gases have the following properties in common: o The noble gases are quite unreactive o They have low boiling points o They are gases at room temperature o You can also find small amounts of the Noble gases in the atmosphere. oHelium, neon and argon form no known compounds.
Helium Noble Gases – Example 5 Properties o Helium has no taste, colour or smell o The gas is produced in massive stars like the sun where 4 hydrogen atoms fuse together. o Melting point ºC o Boiling point – ºC o 2nd lightest elemenet