§2.1 Molecules and Atoms

• Scheikunde
• Middelbare school
• havo, vwo
• Leerjaar 3

§2.1 Molecules en atoms

Chapter 2: Chemical Reactions

Learning Objectives 2.1.

2.1.1 You know that molecules are made up of atoms.

2.1.2 You can explain the difference between elements and compounds.

2.1.3 You can represent molecules using molecular formulae.

2.1.4 You can give the systematic names of molecules.

2.1.5 You can describe the difference at the micro level between a separation method, a phase transition and a chemical reaction.

Remember the particle model?

 

Chemical Reactions...

Molecules are broken down and new molecules are formed.

A reaction can be written down as an equation or process:

molecules go in (reactants), different molecules come out (products).

 

The periodic table; the alphabet of chemistry

Het alfabet and the PT:

Alphabet	PT
Letter	Atom/Element
Word	Molecule
Sentence	Substance
Story	Materials

Atoms in a molecule are connected by atomic bonds (bonds between atoms)

Elements in the periodic table

We know about 118 different kinds of atoms, aka 118 elements

Every element has its own name and symbol 

Practise the names and symbols in table 1!

 

d

Elements

Based on one kind of atom or molecules with one kind of atom (pure)

ggg

g

Compounds

Molecules containing more than one kind of atom.

Molecules can be drawn but they can also be given a molecular formula.

Naming compounds - Nomenclature, systematic

1. First element of compound keeps its own name
2. Second element gets -ide at the end 
3. Greek numbering words are used to indicate how many of each element is in the formula

N2O = dinitrogen oxide                      CCl4  = carbon tetrachloride 

  

Greek:	number
mono-	1
di-	2
tri-	3
tetra-	4
penta-	5
hexa	6

hepta-	7
octa-	8

Name: index comes first

Formula: symbol comes first, followed by index

Never start a name with mono

Practise:

Give the name:

1. N2O5

2. P2I4

3. S2Cl2

Give the formula:

1. phosphorous trichloride

2. dinitrogen monoxide

3. diphosphorous pentaoxide

Recap today

2.1.1 You know that molecules are made up of atoms.

2.1.2 You can explain the difference between elements and compounds.

2.1.3 You can represent molecules using molecular formulae.

2.1.4 You can give the systematic names of molecules.

2.1.5. You know the difference between separation, phase transitions and chemical reactions.

Homework! Read chapter 2.1. and do assignment 1 to 9 

Moleculen en atomen zijn onzichtbaar klein. Als je zuiver water (H2O), zuivere alcohol (C2H6O) en keukenzout (NaCl) met elkaar in een glas mengt, krijg je een heldere, kleurloze oplossing.

Hoeveel soorten atomen zitten er in dat glas?

1. 1
2. 3
3. 5
4. vele miljoenen

Moleculen en atomen zijn onzichtbaar klein. Als je een theelepel zuivere suiker oplost in een glas zuiver water, ontstaat een heldere suikeroplossing.

Hoeveel soorten moleculen zitten er in dat glas?

1. 1
2. 2
3. 3
4. miljoenen

Verbinding

Element

H2

CH4

Cl2

HF

C6H12O6

Na

1. scheiding
2. faseovergang
3. chemische reactie

1. scheiding
2. faseovergang
3. chemische reactie

1. scheiding
2. faseovergang
3. chemische reactie

1. scheiding
2. faseovergang
3. chemische reactie

1. scheiding
2. faseovergang
3. chemische reactie