Topic 5 The Periodic Table

The periodic table  The periodic table is made up of elements, approximately 110, number varies depending on the periodic table.  Rows= periods  Columns = groups  The metals are on the left hand side and the non-metals on the right hand side

Metals and non-metals  Metals have high melting and boiling points and are solids at room temperature (except mercury).  Non-metals have low melting and boiling points and are mainly gases / liquids at room temperature or low melting point solids.

Metals and Non-metals Say whether these elements are metals, non- metals or metalloids H Li Na K Rb Cs Fr Be ScTi Mg VCrMnFeCoNiCuZnGaGeSeBrCaKr YZrNbMoTcRuPdAgCdInSnSbSrTeRh BaHfTaWReOsIrAuHgTlPbBiPoLaAtPt RaRfDbSgBhHsMt??Ac? AlP NO SCl FNe Ar Rn I Si Xe He BC As Silicon (Si) Metalloid Francium (Fr) Metal Scandium (Sc) Metal Krypton (Kr) Non-metal Cobalt (Co) Metal Activity

The modern Periodic Table  Dimitri Mendleev developed the modern periodic table.  He arranged the elements in increasing atomic number and elements with similar properties were put in the same group. He left spaces where he thought elements were yet to be discovered.

Symbols  Give the symbols for the following elements:-  Iron  Lead  Sodium  Potassium

Write a definition for an Element and a Compound  Element is made up of only one type of atom.  Compound is made up of 2 or more different types of atoms of elements that have been chemically combined.  What is the difference between Copper sulphide and Copper Sulphate?

Atomic no. and Mass no.  Next to each element is 2 no.s e.g. 23 Na Na  Which one is the atomic number and the mass number?  What does the Mass number tell you? What does the atomic number tell you?  The bigger No. =Mass No.=Neutrons + Protons  The smaller No = Atomic No.= Protons  REMEMBER Protons = Electrons  Elements are arranged in order of increasing atomic number.

Groups What does this tell you?  The number of electrons in the outer shell represents the group number…  What is similar about Group 2 elements?  All elements in group 2 have 2 electrons in their outer shell.  All elements in the same group have similar properties because they have the same number of electrons in their outer shell

GROUP 7 HALOGENS Halogen Physical State Colour BP and MP Reactivit y FgasYellow ClgasGreen BrliquidBrown Isolid Dark grey DECREASES INCREASES

Reactivity for group 7  Reactivity decreases as you go down the group. So fluorine is the most reactive of the group.  7 electrons in the outer shell.  Elements in group 7 react in similar ways i.e. they all react with sodium.

Compare group 1 metals  Group 1; Lithium, sodium, potassium are all metals which have a relatively low melting and boiling point.  They have 1 electron in their outer shell.  Reactivity increases as you go down the group. So Francium is the most reactive element in group 1.  Elements in group 1 all react with water to produce an alkali and hydrogen.

Sc1 Skills  Fair test  Graphs:- 1.Choose an appropriate scale 2.Plot points carefully 3.UNITS. 4.Line/curve of best fit

QWC…  Longer answers should read well  Science terminology.  Do not repeat question

Pointers for test…  Density measured in g/cm 3  So it is mass divided by volume occupied  When interpreting data refer to what is given in the question i.e X, Y and Z  Do not start calling them the noble gases because you think they are unless asked which group you think they are.

Pointers for test…  If you are asked to compare data i.e. predictions to actual results give specific details from predicted AND actual results i.e. I think the boiling point was predicted correctly as predicted result was 32 o and actual result is 30 o.