Compounds_Booklet(1) Yr 10

Enw / Name:_________________________

Dosbarth/Form: ______________________

Athro/Teacher: ______________________

Geirfa / Keywords

Term DefinitionReactantProduct

AtomElement

CompoundNeutronProton

ElectronMolecule

Positive ionNegative ion

Ionic Compound

Lesson 1, Preserving AtomsLesson Objectives:

1

Know that atoms cannot be created or destroyed in a reaction. Understand that atoms are rearranged.

What do you think happens in a chemical reaction. Put down all your ideas in a list

1.

2.

3.

Compare this list with the person next to you and see if you agree. Now listen to what your teacher has to say about reactions........

Can you now re-write your list?

1.

2.

3.

Every atom has a mass.... it may only be tiny but it’s there.

Let’s take the formation of water as an example. Hydrogen atoms have a mass of 1. Oxygen had a mass of 16.

The word equation for forming water is

Hydrogen + Oxygen Water

The things on the left hand side of this equation are called REACTANTS and the things on the right are PRODUCTS.

The symbol equation is

2 H2 + O2 2 H2O

It’s important that this equation is balanced.... what you start off with on the left of the arrow has to go somewhere and you cannot make something out of thin air so you need enough atoms on the left to make your product.

The left and the right of an equation BALANCE.

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Atom Jam

What are the masses of these things? To do this we will draw the atoms.

1. Draw hydrogen as blue and oxygen as black. 2. When you have drawn them write the masses of the atoms on the

atoms. 3. Then put the total masses under the symbols.

2 H2 + O2 2 H2O

Do you see that you have the same mass in the end that you started with?

Now try the same for these:

Iron + Sulphur Iron Sulphide

Fe + S FeS

Carbon + Oxygen Carbon dioxideC + O2 CO2

Methane + Oxygen Carbon dioxide + Water

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Peer Assessed

Peer Assessed

CH4 + 2 O2 CO2 + 2 H2O

Write down 3 things you have learnt this lesson:

1. 2. 3.

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Practice Question

5

Lesson 2, Compounds:

Lesson Objectives:Understand that compounds are formed when atoms combine and that compounds have formulae.

So, we know that when two or more elements react the atoms rearrange to form a totally new substance with totally new properties called a ....................................

Let’s look at sodium and chlorine. In the boxes below write down all you know about these elements e.g. their appearance, state, uses....... (hint, try using the periodic tables in the lab).

Sodium: Chlorine:

Check your list with a classmate, then with your teacherWrite a word equation for what these two elements will form when they react:

What is this substance.... where might you find it, what is it like and is it anything like the elements that it’s made from?..............................................................

......................................................................................................................

.................................

All compounds have a formula. You already know some formulae (this is the plural). Let’s fill them in

Water

Hydrochloric Acid

Methane

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Peer Assessed

These three are odd examples because they have their own special names. Most other compounds are named by the elements that they contain. Try working out what elements these contain

Compound Name Element One Element Two

Iron Sulphide

Magnesium Oxide

Copper Chloride

Lead Fluoride

All pretty easy, eh?!Well, it gets a bit harder...... what do all the compounds above contain?...................

What about when we have non metals?

Compound Name Element One Element Two

Carbon Monoxide

Carbon Dioxide

Sulphur Dioxide

Carbon Tetrafluoride

What rules have you just learnt?1. ............................................................................... 2. ...............................................................................3. ............................................................................... 4. ............................................................................... 5. ............................................................................... 6. ...............................................................................

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Peer Assessed

Lesson 3, Naming & Drawing Compounds:

Lesson Objectives: Say how many atoms and of what type are present in a compound

when you are given its formula Draw and interpret space filler diagrams

We looked at the names of some compounds last lesson. Now we are going to look at some formulae and work out what we’ve got. Start by matching these up

Calcium oxide CuSO4

Potassium sulphide Mg(OH)2

Magnesium hydroxide CaO

Copper sulphate Na2O

Calcium carbonate AgNO3

Sodium oxide CaCO3

Silver nitrate FeF2

Iron (ll) fluoride K2S

These names are a bit harder aren’t they?

Let’s look at some more rules for names:

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Peer Assessed

If you see ............................ on the end of a formula then the compound is ‘something’ SULPHATE

If you see ........................... on the end of a formula then the compound is ‘something’ CARBONATE

If you see .......................... on the end of a formula then the compound is ‘something’ NITRATE

If you see .......................... on the end of a formula then the compound is ‘something’ HYDROXIDE

These complex ions may have brackets round them.... e.g Ca(OH)2. This doesn’t matter, this is still calcium hydroxide.

But how many atoms have we got?

If you have brackets then you need to multiply what is inside the brackets by the number outside it.

e.g. Ca(OH)2

One calcium atom

TWO oxygen atoms and TWO hydrogen atoms.

Go back to your table and fill in the blank column with the number of atoms that you have in each compound.

Now turn to the person next to you and tell them what you have learnt so far this lesson.

Now we are going to do space filler diagrams

Ok, so it’s not that kind of space...................... In these diagrams, round circles of different colours (black, white and grey on your exam paper) represent atoms.

This could represent something like nitrogen (N2)

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This could be HCl. Which colour do you think is the hydrogen?..............................

Why?............................................................................................................................................

So far so good, let’s put what you know together by answering these questions....

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Feedback

Mark /6

If you had less than 6 what do you need to look at again?...........................................

......................................................................................................................

.................................

......................................................................................................................

.................................

Lesson 4, Ionic Bonding:

Lesson Objectives: Say what happens during ionic bonding Say why this happens

Everybody wants to be a noble gas......

The noble gases are group ..................... on the

periodic table. They include

1. 2. 3.

What’s so special about these elements? Use the dingbat below to see if you can work it out................................

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Peer Assessed

Atoms want to be like noble gases because ...........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................Ionic Bonding happens when a metal and a non metal react.

Write down the names of three (different!) ionic compounds

1. 2. 3.

Let’s do a common example... salt, aka sodium chloride

What is the easiest way for sodium to get a full outer shell? Let’s draw its electrons to help us......

It’s easier to .......................................................If the atom does this what will happen to the balance between the positive protons and the negative electrons?

The atom will be left ............................... charged and is now called an IONLet’s draw it.....

+

12

All metals lose electrons to form positive ions

What about the chlorine?

It’s easier to .......................................................If the atom does this what will happen to the balance between the positive protons and the negative electrons?

The atom will be left ............................... charged and is now called an IONLet’s draw it.....

-

All non-metals gain electrons to form negative ions

We now have Na+ and Cl-.These charges are opposite so the two ions attract one another and form strong electrostatic bonds.

Ok, deep breath, scream (quietly!). Write down one thing you do understand and one question you have....

I get that....................................................................................................................................

I don’t get...................................................................................................................................

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1. Now let’s look at what happens in magnesium oxide

Magnesium

Will make

Oxygen

Will make

So we have Mg and O

These charges are opposite so the two ions attract one another and form strong electrostatic bonds.

2. Calcium Fluoride

Calcium

Will make

How many electrons does this release?...........................How many electrons can fluorine grab?...........................How many fluorines do you need?......................................

Will make

The principle is the same but here we have one Ca2+ and two F-

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The formula for the compound is CaF2

3. Now try your own drawings for sodium oxide

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TeacherAssessed

Practice Question

Feedback

Mark /3

If you had less than 3 what do you need to look at again?...........................................

......................................................................................................................

.................................

......................................................................................................................

.................................

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Peer Assessed

Lesson 5, Writing Formulae

Lesson Objectives: Use the table given to you in your exam to write the formulae of

compounds

A positive ion is an atom that has..............................................................................

A negative ion is .............................................................................................................

The overall charge of a compound must be ............................................................

You can work out the formulae of compounds using the long winded method that we looked at last lesson where we worked out the way some ionic compounds form. This takes too long and can’t be used for complex ions...... remember these?

1. Sul..........2. Nit..........3. Car.........4. Hy..............

Inside your exam paper (at the back, probably) you will get

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You need to be able to match up any of the positives with any of the negaties.

Example 1- Potassium bromide

This is K+ with Br-

As the charges are the same the formula is just KBr. “Simples!”

Example 2- Calcium Fluoride

Ca2+ with F-

Write them next to each other and write in the number of the charge on the fluorine

ions Ca2+ F1-

swapped charges 1 2number of ions 1 2

Formula CaF2

Your Turn 3- Magnesium Iodide

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Self Assessed

Your turn 4- Copper (ll) oxide

Example 5- Copper (ll) Carbonate

ions Cu2+ CO32-


Formula CuCO3

Example 6-Magnesium Hydroxide

ions Mg2+ OH1-


Formula Mg(OH)2You need the brackets because hydroxide is a complex ion and you need two of all of it.

Your turn 7- Ammonium chloride

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Homework

Write the formulae AND a list of the number of atoms that all the following contain

Name Formula Number of atoms

1 Copper (ll) sulphate

2 Silver nitrate

3 Potassium sulphate

4 CaO

5 K2S

6 Sodium hydroxide

7 Lithium nitrate

8 Calcium bromide

9 Iron (lll) hydroxide

10 Ammonium carbonate

Mark /20

Targets............................................................................................................................

Topics Red Amber Green

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(a) know that in a chemical reaction, atoms ate rearranged but none are created or destroyed

(b) understand that new substances called compounds are formed when atoms of two or more elements combine and that each compound has its own chemical formula

(c) be able to interpret given chemical formula i.e. name the elements, state the number of atoms of each element and the total number of atoms present, including formulae containing hydroxide, nitrate, carbonate and sulphate (sulfate) ions

(d) be able to draw and interpret space-filler type diagrams for simple molecules using a key (showing an appreciation of which atoms are joined to which)

(e) understand that electrons are transferred from metal atoms to non-metal atoms, forming positively charged metal ions and negatively charged non metal ions, when ionic compounds are formed

(f) be able to write chemical formulae for ionic compounds given the formulae of the ions that they contain, including formulae containing hydroxide, nitrate, carbonate and sulphate ions

Summary Checklist : Atoms and Compounds

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Compounds_Booklet(1) Yr 10

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