1.
Molecular Models
Chemistry Lab Work 1

2. Theme and Aim of the Work
Theme and Aim of the Work
To construct molecules of compounds
To construct models of crystal structures
Materials: student molecular model set

3. Types of Molecular Models
Types of Molecular Models
Ball-and-stick model
Framework model
Space-filling model

4. Student Molecular Model Set Types of Chemical Bonds
Student Molecular Model Set
Types of Chemical Bonds
Single bond
Double bond
Triple bond

5. Representation of Atoms
Representation of Atoms
Carbon
Oxygen
Chlorine (Halogens)
Metals
Hydrogen
Nitrogen
Sulphur

6. Types of Molecular Structures
Types of Molecular Structures
Linear
Bent
Trigonal planar
Square planar
Tetrahedral
Octahedral

7. Chemical Bonding
Ionic bonding Electrons are completely transferred from one atom to another.
Covalent bonding Atoms share electrons.

8.
What is a covalent bond?

9.
What is a covalent bond?
A covalent bond is formed when atoms share valence electrons.
H  +  H  H - H

10.
What is the difference between a single covalent bond and a multiple covalent bond?

11. A triple bond means that three electron pairs are shared.
What is the difference between a single covalent bond and a multiple covalent bond?
A single bond means that only one electron pair is shared between two atoms.
H  +  H  H - H
A double bond means that two electron pairs are shared.
O = O
A triple bond means that three electron pairs are shared.
 N  N

12.
What compound is it?

13.
What compound is it?
Ammonia
NH3

14.
What compound is it?

15.
What compound is it?
Carbon dioxide
CO2

16.
What compound is it?

17.
What compound is it?
Hydrogen chloride
HCl

18.
What compound is it?

19.
What compound is it?
Water
H2O

20.
What compound is it?

21.
What compound is it?
Hydrogen sulphide‏
H2S

22.
What is incorrect?

23.
What is incorrect?

24. Why? Bounds should be single, the molecular structure should be bent.
Why?
Bounds should be single, the molecular structure should be bent.
Wrong bonding

25. Why are the models incorrect?
Why are the models incorrect?
The molecular structure should be linear
The bond should be double.
Correct

26.
Crystal Models

27. What is characteristic for crystals with covalent bonds?
What is characteristic for crystals with covalent bonds?

28. What is characteristic for crystals with covalent bonds?
What is characteristic for crystals with covalent bonds?
Crystals are usually hard and brittle.
Their melting point is high.
Covalent substances are insoluble in water.
Example : diamond

29. How to construct a diamond model:
How to construct a diamond model:
We use
models of carbon atom with four bonds (tetrahedral).
models of single bonds.

30. What is characteristic for crystals with ionic bonds?
What is characteristic for crystals with ionic bonds?

31. What is characteristic for crystals with ionic bonds?
What is characteristic for crystals with ionic bonds?
Crystals are usually brittle.
Their melting point is high.
Ionic substances are soluble in water.
Example : NaCl

32. How to construct a NaCl model:
How to construct a NaCl model:
We use
models of Na+ ions.
models of Cl- ions.
models of single bonds.

33. The Ionic Crystal Model of Sodium Chloride(NaCl)
The Ionic Crystal Model of Sodium Chloride(NaCl)

34. Thanks for your attention
G a SOSPg Znojmo, Czech R.
Thanks for your attention