PREZI

This is the work I have done with Marina, I hope you enjoy!

BLANCA FERNÁNDEZ OCHOA

VOCABULARY

UNIT 5:

Have a lie-in: Get up late
Eventually: At some later time
Have a sleep over: Sleep in a friend´s house

UNIT 7:

Fightback: Return to fight
Polite: Showing good manners;  polite , courteous.
Bite: To cut or tear with the teeth.
Shy: Timid


 

OXYGEN

 

 

OXYGEN

 

 

 

What is it?

 

• Oxygen is a chemical element. It is a member of the chalcogengroup on the periodic tableand is a highly reactive nonmetaland oxiding agent.
• Is the 3rd most abundant element in the universo.
• Oxygen was discovered by Carl Wilhelm and Joshep Priestley.

Characteristics:

• At standart temperatura and pressure, oxygen is a colorless, odorless tasteless gas.
• Oxygen is the most abundant element by mass in terrestrial biosphere, air, sea and land.
• around 0.9% of the mass of the Sun is oxygen.

Aplications:

• Medical
• Life support and recreational use
• Industrial
• Science

 

How we obtain it?

• Photosyntesis and respiration:

In nature, free oxygen is produced by the light-given splitting of wáter during oxygenic photosyntesis.

• Living organims:

The free oxygen partial pressure in the body of a living vertebrate organims is highest in the respiration system, and lowest in arterial system.

 

Properties:

• Atomic number: 8
• Valence: 2
• Oxidation state: -2
• Atomic mass: 15,9994
• Boiling point: -183
• Fusion point: -218,8
• Isotopes: 3 nuclear stable and 14 unestable