Quick quiz 1.What is found in the periodic table? 2.What are the rows called? 3.What are the columns called? 4. What element is found in: a)Group 8 period 2- Ne (neon) b)Group 6 period 2- O (oxygen) c)Group 1 period 4- Na (sodium)
This dotted line is called The Staircase – it divides metals (left) from non-metals (right)
Atoms ELEMENTS are made up of ATOMs. ATOMs are all made up of protons, neutrons and electrons. The Nucleus – this contains neutrons and protons Electrons – these orbit around the nucleus
Different elements have different types of atoms. What the difference? Protons =2 Protons =4 Helium Beryllium
Atomic Number alwaysThe atoms of same elements always contains the same number of protons. E.g. –Hydrogen atoms always contain 1 proton –Carbon atoms always contain 6 protons –Magnesium atoms always contain 12 protons The number of protons is the atomic number. It is the smaller of two number 12 C 6
There are 3 parts of an atom Type of sub atomic particle Relative charge Proton+1 (positive) Neutron0 (neutral) Electron-1 (negative) 1/2000 of the size of a proton
How Many Protons? Here is some data about elements taken from the Periodic Table. What is the atomic number of the elements? 23 Na 11 56 Fe 26 119 Sn 50 19 F 9 27 Al 13 11 26 50 9 13 Activity
What element is it? Atomic number. 12-Magnesium (Mg) 8- Oxygen (O) 6- Carbon (C) 20-Calcium (Ca) 3- Lithium (Li) 2- Helium (He)
Atomic number Atomic number = number of protons. Atomic mass is the number of protons and neutrons added together 12 C 6
Atoms In atoms number of protons = number of electrons So if the atomic number is 8 it will have, 8 protons and 8 electrons
Complete as a class AtomProtons + Electrons - Charge Helium Nitrogen Oxygen Magnesium Sodium Activity Symbol
What is an isotope? Different forms of the same element. Same atomic number BUT a different number of neutrons and thus a different mass number. Eg O 16 8 99.76% of oxygen atoms have this configuration. 0.04% have the mass number of 17 0.20% have the mass number of 18
*Drawing Atoms* Aim: To accurate diagrams of the electron structure of the first 20 elements.
How Are Electrons Arranged? Electrons are not evenly spread. The exist in layers known as shells. electron configuration.The arrangement of electrons in these shells is often called the electron configuration. 2nd Shell 1st Shell 3rd Shell 4th Shell
Electron configuration Shows how electrons are organised at an atomic level. Shell1st2nd3rd4th Max numbers of electrons 2882
Which Shells Do Electrons go into? Opposites attract. Protons are positive (+) and electrons are negative (–) charged. Electrons will occupy the shells nearest the nucleus unless these shells are already full. 1st Shell: Fills this first 2 nd Shell: Fill this next 3 rd Shell: And so on
1+ ion Protons Electrons 1- ion Protons Electrons Ions and Electron Structures 1.Ions are atoms that have either extra electrons added or electrons removed. e.g. Atoms Protons Electrons Lose 1 electron Gain 1 electron So in ions the number of electrons no longer equals the number of protons
Na Bye! The Electrons in a Sodium Ion atom In the sodium atom Atomic number = number of protons = 11 Number of electrons = 11 Electron arrangement: 2.8.1 (Incomplete Shell) Na+ Electron lost Electron arrangement: 2.8 (Full Shells) 23 Na 11
Mg The Electrons in a Magnesium Ion atom In the magnesium atom Atomic number = number of protons = 12 Number of electrons = 12 Electron arrangement = 2.8.2 (Incomplete shell) Mg 2+ Electron arrangement 2.8 (Full Shells) Bye! 2 electrons lost 24 Mg 12
The Lithium Ion Li 3 2 1 1st Shell = 2: full 2nd Shell = 1: not full 2.1 1 How many electrons? How many electrons in the first shell? How many electrons in the second shell? What electron arrangement? How many electrons to lose? New electron arrangement? Include a diagram 2.(0) Bye! Li + 7 Li 3 Activity
The Boron Ion B 5 2 3 1st Shell = 2: full 2nd Shell = 3: not full 2.3 3 How many electrons? How many electrons in the first shell? How many electrons in the second shell? What electron arrangement? How many electrons to lose? New electron arrangement? 2.(0) Bye! B 3+ 11 B 5 Activity
Open to valence table 5.1 Draw a before and after using a Bohr diagram showing the following atoms becoming ions. Sodium Oxygen Chlorine Calcium Nitrogen Aluminium
Ionic Compounds Once an ion has been created it will attract ions of the opposite charge they form ionic compounds. For example magnesium + oxide = magnesium oxide To write this as a chemical formula you need to take into account the ions charges (valencies) Magnesium has a positive charge of 2 while oxide has a negative charge of 2.
Ionic Formulas Step 1 - write the name and symbols (the positive goes first) MagnesiumOxide 2+2- MgO Write the valencies above the symbols Step 2 - crisscross the valencies to get correct subscripts and leave out the + & - signs MagnesiumOxide 2+2- Mg 2 O 2 Step 3 - write the correct formula with subscripts Mg 2 O 2 = MgO (you can simplify this to MgO as each has 2 they cancel each other out)
Ionic formulas What happens when you try the following Potassium + oxide Your new formula looks like this potassiumoxide 1+ 2- K 2 O 1 K 2 O When the charge is one only you can leave this out
Ionic Formulas Try these in your book (write ALL STEPS) 1.Calcium + oxide 2.Barium + oxide 3.Silver + chloride 4.Sodium + bromide 5.Lead + permanganate
Ionic formulas When they get more complex- Zinc + nitrate 2+1- Zn(NO 3 ) Zn(NO 3 ) 2 Potassium + sulfate 1+2- K(SO 4 ) K 2 SO 4
Creating an ionic compound Aim: to make the ionic compound Magnesium oxide and explain its bonding. What you know about Magnesium and Oxygen. Colour, solid liquid or gas, electron structure. Use pictures
Equipment & Safety Equipment Goggles 2cm strip of Mg Heat proof mat Tongs Bunsen burner Safety While heating Mg DO NOT look directly at it. Ensure all heated material stays on heat proof mat Ties in
Observations 1.What did you see hear and smell? 2.What was the product formed? 3.What did it look like? Explaining observations 1.Why did you see or hear something? 2.How can you explain why magnesium and oxygen have combined? 3.Use the electron configuration. 4.How many atoms form the compound? 5.Does the properties change of Mg and O? 6.Why does this happen? 7.Write and equation to show this chemical reaction.
gainingThese are ions formed by the atom gaining one or more electrons. anionsThey are called anions. This is because during electrolysis they move towards the anode. equal to the number of electrons that the atom has gainedThe charge on the ions is equal to the number of electrons that the atom has gained. In equations the charge is usually shown above and to the right of the symbol. (E.g.. O 2- ). Negative Ions. Gain 1 e - - Gain 2 e - 2- Gain 3 e - 3- It is nearly always non-metal atoms that gain electrons Ions usually have OUTER electron shells that are either completely full or else empty
The Electrons in a Sulphide Ion. atom In the sulphur atom Atomic number = number of protons = 16 Number of electrons = 16 Electron arrangement: 2.8.6 (incomplete shell) Electron arrangement 2.8.8 (Full shells) 2 electrons gained SS 2- 32 S 16
The Electrons in a Fluoride Ion. atom In the fluorine atom Atomic number = number of protons = 9 Number of electrons = 9 Electron arrangement: 2.8.7 (incomplete shell) Electron arrangement 2.8.8 (Full shells) 1 electron gained FF 2- 19 F 9
The Oxide Ion 16 O 8 O 8 2 6 1st Shell = 2: full 2nd Shell = 6: not full 2.6 2 How many electrons? How many electrons in the first shell? How many electrons in the second shell? What electron arrangement? How many electrons to gain? New electron arrangement? 2.8 O 2- Activity
Drag the words at the top to their correct places in the sentences.
1.Which of the following is not a sub- atomic particle? A.Proton. B.Isotope. C.Neutron. D.Electron.
2.The element Cobalt has a relative atomic mass of 59 and an atomic number of 27. Which of these is a true statement about each neutral cobalt atom? A.It contains 59 neutrons. B.It contains 27 electrons. C.It contains 32 protons. D.It contains equal numbers of neutrons and electrons.
3.The Periodic Table displays iron as shown below. This indicates that Fe atoms: A.contain 56 neutrons. B.contain 30 electrons. C.contain 26 protons. D.contains more protons than neutrons. 56 Fe 26
4.Bromine consists of a mixture of two isotopes: Bromine-79 and Bromine-81 Which of the following is true: A.Both isotopes contain 35 protons. B.Bromine 79 contains 46 neutrons. C.Bromine 81 contains 44 neutrons. D.Bromine-81 is more reactive than bromine- 79. 80 Br 35