Atoms And Elements Key words; Atom, Compound, Electron, Element, Symbol

By the end of the lesson I can: Learning Objectives By the end of the lesson I can: Recall that all substances are made up of atoms Describe and explain what is inside an atom Describe how elements contain only one type of atom Understand that symbols are used for atoms to show what happens in chemical reactions. Know that all 100 known elements are listed on the periodic table and groups have similar properties

atom – The smallest particle that can exist on its own. compound – Substance made up of two or more different elements that are chemically joined together. element – Substance made up of only one type of atom.

Atoms – the building blocks All substances are made from very tiny particles called atoms. John Dalton had ideas about the existence of atoms about 200 years ago but only relatively recently have special microscopes (called electron microscopes) been invented that can ‘see’ atoms. The yellow blobs in this image are individual gold atoms, as seen through an electron microscope.

Daltons Atomic Theory Devise the LAW OF CONSERVATION OF MASS All matter is made up of tiny particles called atoms. Atoms cannot be created or destroyed (as stated in the Law of Conservation of matter) All atoms of an element are THE SAME Atoms of one element are completely different to the atoms of another element Atoms combine in small numbers to form molecules Devise the LAW OF CONSERVATION OF MASS (2 mins)

Even smaller particles Scientists now know that atoms are actually made from three even smaller particles: These particles are so small weighing them in grams is meaningless So instead we say Protons and Neutrons have a mass of one unit, whereas, electrons are smaller, about 1/2000 of a unit (effectively nothing) Some particles have an electrical charge proton neutron electron

Draw an atom and try to label it with the 3 sub atomic components Whilst this is still not completely accurate, this is how we draw an atom when we are learning science at secondary school Draw an atom and try to label it with the 3 sub atomic components

This is a bit more accurate because we have no idea of where the electrons are at any one time – they are in a cloud called the electron cloud.

Inside an atom Draw an atom and annotate it Use a ‘METAPHOR’ to explain the atom concept to a 10 year old child (year 6) Atoms always have the same number of protons and electrons, making them neutral

Imagine a hoola hoop Now imagine a ball somewhere in the middle of the hoop. This represents the nucleus Now imagine a car running round the outside somewhere. This represents an electrons

What is left is a very simple and not completely accurate model of an atom

Include annotated detail 1 +1 1 1/2000 -1

Elements There are about 100 different elements listed on the periodic table of elements Elements are made up of just one type of atom. Each atom in an element has the same number of protons. Different elements have different numbers of protons in their atoms. The atomic number of an element is its number of protons. The mass number of an element is its number of protons and neutrons There is an equal number of protons and electrons How can you find the number of neutrons? How can you find the number of ELECTRONS?

Symbols O Na Every element has a symbol as a shorthand way of writing it down. Symbols have one or two letters. The first letter is always a capital letter. The second is always lower case. K Cl

CHeSS SON COAl SHOAl BIN Write down the symbols for each element listed and use these to spell out a word that matches the clue. Board game: carbon, helium, two sulphurs Relative: sulphur, oxygen, nitrogen Fuel: carbon, oxygen, aluminium Group of fish: sulphur, hydrogen, oxygen, aluminium For the rubbish: boron, iodine, nitrogen CHeSS SON COAl SHOAl BIN

An element is a substance made up of only one type of atom. In some elements, the atoms are joined in groups of two or more. A particle containing atoms grouped in this way is called a molecule. Oxygen is an element made up of oxygen atoms only. How many atoms are there in an oxygen molecule? Other elements, that contain atoms joined in molecules are hydrogen, nitrogen, chlorine and bromine.

There are groups of two atoms in each molecule. In some elements, the atoms are joined together and form molecules. Combining the symbols of the atoms in a molecule gives you the formula of the molecule. What is the formula for the molecules in each element? O2 oxygen There are groups of two atoms in each molecule. H 2 hydrogen N2 nitrogen

CREATING ELEMENTAL POETRY The original http://www.youtube.com/watch?v=GFIvXVMbII0 The rap http://www.youtube.com/watch?v=pmTXtbRR7c0&feature=related Everyone can do it!!! http://www.youtube.com/watch?v=QWkVO6Bp8VM&feature=related

CREATING ELEMENTAL POETRY Use what you’ve heard and the periodic table and textbooks to write a poem/song about EITHER an element and its properties OR 2. a number of elements on the periodic table

By the end of the lesson I can: Learning Objectives By the end of the lesson I can: Recall that all substances are made up of atoms Describe and explain what is inside an atom Describe how elements contain only one type of atom Understand that symbols are used for atoms to show what happens in chemical reactions. Know that all 100 known elements are listed on the periodic table and groups have similar properties

Atoms and symbols All substances are made up of p______. The smallest p_____ that can take part in a chemical reaction is called an a___. Elements are substances that each contain only _______ of atom. The atoms of each element are represented by a symbol. Examples of symbols used for elements are O (used for ______), N (used for _______) and Cu (used for ______). articles article tom one type oxygen nitrogen copper

More work on symbols Fill in the gaps in the table below. Name of element Symbol Chlorine Cl Carbon C Silver Ag Bromine Br Sodium Na

How are the elements arranged? Answer: Using the Periodic Table Vertical columns are called ___________ and horizontal rows are called ___________. groups periods

Elements, mixtures and compounds Elements – these are substances containing only ______________. For example, sodium is an element and is made up of sodium atoms only. Compounds – these are substances made up of two or more types of atom. These atoms are joined together chemically. For example, carbon dioxide contains carbon and oxygen atoms joined together by chemical bonds. one type of atom

Mixtures – these are not pure substances Mixtures – these are not pure substances. The compounds and/or elements making them up are not joined chemically. For example, air is a mixture of gases like oxygen (an element) and carbon dioxide (a compound).

Elements, mixtures and compounds, continued Classify the following substances as elements, mixtures or compounds. mixture compound element

How do we name compounds? The rules are: If there are two elements present, then the name ends in –IDE. For example, the formula CuS represents the compound _________ide. If there are three elements present and the third one is oxygen, then the name ends in –ATE. For example, the formula CuSO4 represents _________ate. copper sulf copper sulf

Naming compounds, continued Name the compounds in the table below. Formula Name AlCl3 CuO Fe2O3 CaSO4 CaCO3 MgBr2 NaNO3 Aluminium chloride Copper oxide Iron oxide Calcium sulfate Calcium carbonate Magnesium bromide Sodium nitrate

Chemical reactions The substances that react are called the REACTANTS. The substances formed are called the PRODUCTS. REACTANTS PRODUCTS To represent chemical reactions we write word equations or symbol equations.

Chemical reactions, continued Write word equations for the following reactions 1 When sodium is burned in oxygen, sodium oxide is formed. sodium (s) + oxygen(g) sodium oxide(s) 2 When solid calcium carbonate is heated, it decomposes into solid calcium oxide and carbon dioxide gas. calcium oxide(s) carbon dioxide(g) + heat Calcium carbonate (s)

Does the mass change during a chemical reaction? The answer to this is ___. NO For example, when 56 g of iron reacts with 32 g of sulfur iron sulfide is formed. The mass of the iron sulfide formed is __ g. 88 When 48 g of magnesium is heated in oxygen, 80 g of magnesium oxide is formed. What mass of oxygen is needed to react with the magnesium? The answer is __ g. 32

Burning fossil fuels The three fossil fuels are: Coal, oil and natural gas. When the fossil fuels are burned in enough air they always form water and carbon dioxide. Carbon dioxide is a __________ gas and is linked to g____ w______. greenhouse lobal arming Write the word equation for methane (natural gas) burning in oxygen. methane(g) + oxygen(g) carbon dioxide(g) + water(l)

The Reactivity Series Metals are arranged in order of how reactive they are. A more reactive metal will displace a less reactive one from its compounds. For example, zinc will displace copper from copper sulfate to give zinc sulfate plus copper. The word equation is: zinc(s) + copper sulfate(aq) zinc sulfate(aq) + copper