8th Chemistry - Chemistry of Water

St. George's College

Subject: 8th CHEMISTRY

Class:

Teacher's notes

Objectives

Chemistry of Water

Vocabulary Link and Learn

Date: In‐Class Survey

September 14th

Prepared by

2009 1

8th Milton A ‐ Chemistry of Water Name

Oral Intervention

Sergio María Fernanda Alejandra Almendra Anna Paula Sandra E‐C Maia María Belén Alfredo Kinley Arianne Sandra M. Fiorella Rodrigo Giulia Jaime Stefano Bruno

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8th Milton Alpha ‐ Chemistry of Water Name

Oral Intervention

Marcelo Antonella Paulo Alejandro Brenda Diego Gabriel Valeria Giuliana Joshua María Gracia Gonzalo N. Rodrigo Paolo Gonzalo R. Giorgio Nicolás María Claudia

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Let's remember previous learned concepts...

Why is Water important?

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Hydrogen Bonding • Certain substances such as H2O, HF, NH3 form hydrogen bonds, and the formation of which affects properties (melting point, boiling point, solubility) of the substance.

• Other compounds containing OH and NH2 groups also form hydrogen bonds.

• Molecules of many organic compounds such as alcohols, acids, amines, and aminoacids contain these groups, and thus hydrogen bonding plays an important role in biological science.

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Hydrogen Bonds in DNA

http://tinyurl.com/ygoej6

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New knowledge beginning......

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The Water Cycle

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Water in the World

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Characteristics of Water • Certain molecules have an uneven distribution of positive and negative charges on its atoms. For example: WATER.

PHYSICAL

The 5 most common are: temperature, taste, colour, odour and turbidity.

CHEMICAL

The most important chemical characteristics of water are its acidity, alkalinity, hardness, and corrosiveness.

CHARACTERISTICS

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Characteristics of Water • The most common and unusual liquid is Water.

• A rare characteristic of water, is the fact that it is liquid at room temperature, for a molecule of such low molar mass.

• The freezing and boiling points of water are much higher than one might expect from a comparison of these properties to those of similar substances.

What freezing and boiling points would you expect for the molecule of water from the information in the table?

Freezing Point

Boiling Point

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Properties of Water • Most properties of water are anomalous.

• As in other liquids, the density of water increases when the temperature is lowered. But in the water molecule, only down to 4°C. • Below this temperature, the liquid density decreases.

• The density of ice (solid water) is higher than that of liquid water. Water is one of very few liquids, whose solid form floats.

• This property has significant consequences for bodies of water: lakes, lagoons, etc. The temperature at the bottom is never lower than 4°C, unless the body of water freezes completely from surface to bottom.

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Properties of Water ADHESION COHESION

• Water molecules are attracted to other molecules of water. This is called Cohesion.

• Water can also be attracted to other materials. This is called Adhesion.

• This is explained by the uneven distribution of charge in the molecule of water, generating electrostatic attraction and repulsion.

• Those interactions give water its cohesive and adhesive properties.

SURFACE TENSION

Is the cohesion of water molecules at the surface of a body of water.

CAPILLARY ACTION

• Surface tension is related to the cohesive properties of water.

• Capillary action however, is related to the adhesive properties of water.

Example: Place a straw into a glass of water. The water 'climbs' up the straw. What is happening is that the water molecules are attracted to the straw molecules.

• Capillary action is limited by gravity and the size of the straw. The thinner the straw or tube the higher up capillary action will pull the water.

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SURFACE TENSION

CAPILLARY ACTION

ADHESION COHESION

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Water Quiz Click Here

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Work in Class ‐ Milton Gather up with your group, read the material and books available to prepare an Infography about:

WATER

1. Water: Necessary characteristics and procedures to make it safe to drink.

Bascones, Navarro, Espinoza‐Cullere.

2. Water and Industrial Activities: What are the consequences in nature's water due to industrial activities.

Muñoz, Etchart, Stromsdorfer.

3. Water as a Product: Investigate and compare and contrast the characteristics and properties of the 5 most expensive liquids in the world and water.

Mass, Gomez, Seminario.

4. Water in the Cell: Describe the characteristics and biochemical activity of water in the cell and its importance in life.

Solari, Olivari, Caceres.

5. Toxic Water: Describe the situations in which water is toxic and its implications in society.

Lovaton, Coronado, Alarcon.

6. Future of Water: Describe 3 possible scenarios in the future of our planet where water plays a central role.

Figueroa, Arbe, Angulo, Fung.

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Work in Class ‐ Milton Gather up with your group, read the material and books available to prepare an Infography about:

WATER

1. Water: Necessary characteristics and procedures to make it safe to drink.

Aguilar, Vergara, Mispireta.

2. Water and Industrial Activities: What are the consequences in nature's water due to industrial activities.

Acosta, Sampietro, Orrego.

3. Water as a Product: Investigate and compare and contrast the characteristics and properties of the 5 most expensive liquids in the world and water.

Valle, De La Puente, Ranilla.

4. Water in the Cell: Describe the characteristics and biochemical activity of water in the cell and its importance in life.

Navarro R., Green, Belevan.

5. Toxic Water: Describe the situations in which water is toxic and its implications in society.

Gonzales , Arriaran, Navarro G. 6. Future of Water: Describe 3 possible scenarios in the future of our planet where water plays a central role.

Alarco, Chinchay, Fernandez.

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Teacher's Notes This class has been designed to cover the topics of Chemistry of Water from Monday, September 14th till Friday, September 18th.

For further knowledge about this topic: 1. Conduct a thorough search under the topic: Chemistry of Water on the Web, books and magazines.

2. If findings are not specific, ask your teacher for suggestions.

BACK 18

Objectives • Identify and describe the properties, functions and importance of the molecule of Water.

Note: All, or most, of the objectives will be covered during class time, however the student must be responsible for those objectives not covered or concluded.

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Vocabulary • • • • • •

Melting Point Boiling Point Density Surface Tension Tension‐Cohesion Dipole

Note: Most of the vocabulary words will be covered during class time, however the student must be responsible for those words not covered or concluded.

BACK 20

Link and Learn You can visit the following websites to improve your understanding on the present topic: • • • •

http://bit.ly/XjtI4 http://science‐learning2009.wikispaces.com http://learningandscience.blogspot.com http://libraryatstgeorge.blogspot.com

BACK 21

Prepared by

Gerardo LAZARO Science Lead Teacher Email: glazaro@sanjorge.edu.pe Wiki: http://science‐learning2009.wikispaces.com Blog: http://learningandscience.blogspot.com Twitter: http://twitter.com/glazaro

BACK 22

SURVEY If you want to contribute in improving your Chemistry class, click in the survey link:

Term III ‐ 8th A ‐ Class 6

Term III ‐ 8th Alpha ‐ Class 6

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Resources Used Slide (Group)

Description

Resource

Origin

G1 ‐ 2

Image

Milton

http://bit.ly/XQqEw

G1 ‐ 3

Image

Milton

http://bit.ly/XQqEw

G1 ‐ 4 Animation Idea

Notebook Gallery

G1 ‐ 5

Hydrogen Bond in Water 1 Image Animation Hydrogen Bond in Water 2

http://tinyurl.com/m9yvw8 http://tinyurl.com/lh8ro6

G1 ‐ 6

Animation DNA 1 DNA 2 Image

http://tinyurl.com/mygfju http://tinyurl.com/ygoej6

G1 ‐ 7

Animation Check this out

Notebook Gallery

G1 ‐ 8 Animation Water Cycle G1 ‐ 9

Animation Global Distribution of Water

Unknown Unknown

G1 ‐ 10 Images

Water Molecule Senses Chemicals

http://tinyurl.com/lh8ro6 http://bit.ly/2lKRjX http://bit.ly/un2Dh

G1 ‐ 11 Image

Table

http://bit.ly/oS4yU

G1 ‐ 12 Images

Density of Water Triple Point

http://bit.ly/SaU0C http://bit.ly/RvazO

G1 ‐ 14 Images

Surface Tension Adhesion‐Cohesion Capillary Action

http://bit.ly/vz35G http://bit.ly/13vfts http://bit.ly/fBsb

G1 ‐ 15 Image

Questions

http://bit.ly/1mVVa1

G1 ‐ 19 Images

Molecular Geometry 1

Unknown

G1 ‐ 20 Image

Molecular Geometry 2

http://tinyurl.com/n5yvbw

G1 ‐ 19 Animation Ionic vs Covalent Bonding

http://tinyurl.com/lcghho

G1 ‐ 20 Animation Covalent Bonding

http://tinyurl.com/l4psxt

G1 ‐ 21 Animation VSEPR

Unknown

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8th Chemistry Grade: Subject: Date:

«grade» Chemistry «date»

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What was your UNDERSTANDING of the topic: "Chemistry of Water"?

1

A

I understood 25% of the whole topic

B

I understood 50% of the whole topic

C

I understood 75% of the whole topic

D

I understood 100% of the whole topic

E

I didn't understand the class

26

2

What was your level of EFFORT to understand the topic?

A

My effort level was 25%

B

My effort level was 50%

C

My effort level was 75%

D

My effort level was 100%

E

I didn't put any effort

27

3

What RESOURCES helped you understand the topic?

A

Text

B

Images

C

Animations

D

Videos

E

Teacher's Speech

F

None

G

Other

28

4

How does the SMART Board help you understand the topic?

A

It helps me visualize concepts

B

It helps understand difficult concepts

C

Touching things helps me learn

D

Interacting with the information makes it easier to understand

E

I prefer less effects or audiovisual resources

F

It doesn't really help much

G

I don't like it

29

8th Alpha Grade: Subject: Date:

«grade» Chemistry «date»

30

What was your UNDERSTANDING of the topic: "Chemistry of Water"?

1

A

I understood 25% of the whole topic

B

I understood 50% of the whole topic

C

I understood 75% of the whole topic

D

I understood 100% of the whole topic

E

I didn't understand the class

31

2

What was your level of EFFORT to understand the topic?

A

My effort level was 25%

B

My effort level was 50%

C

My effort level was 75%

D

My effort level was 100%

E

I didn't put any effort

32

3

What RESOURCES helped you understand the topic?

A

Text

B

Images

C

Animations

D

Videos

E

Teacher's Speech

F

None

G

Other

33

4

How does the SMART Board help you understand the topic?

A

It helps me visualize concepts

B

It helps understand difficult concepts

C

Touching things helps me learn

D

Interacting with the information makes it easier to understand

E

I prefer less effects or audiovisual resources

F

It doesn't really help much

G

I don't like it

34