Review exercises 2 ESO

• Balance these chemical equations:

1. Co + O2 => Co2O3
2. C4H8 + O2 =>  CO2 +  H2O
3. Fe + HCl =>  FeCl2 +  H2
4. Na + H2O => Na2O + H2

• Determine wheter these are chemical or physical:

1. Melting of ice
2. Oxidation of a wet screw
3. Solving salt into water
4. Drilling a wall
5. Photosynthesis

• Imagine this reaction of a fuel: CnH2n + O2 => CO2 + H2O. Tell if these factors will affect the reaction rate

1. The fuel is cooled to solid state
2. The fuel is vaporised
3. We control the temoperature reaction to 30ºC. 
4. We let the reaction temperature reach 1500ºC

• Tell if these proccess is biological or industrial:

1. Synthesis of a polymer
2. Human breathing
3. Mythosis
4. Cracking of oil

• Are these statements true or false. Tell why

1. The combustion of fuels affects the ozone layer.
2. CFCs provoque the ozone-s layer depletion
3. Global warming is only provoqued by the industrial activity
4. Atmospheric polution only provoques global warming
5. Soil polution has to do with waste dumping.
6. Only industries pollute water

Chemistry and the environment

Watch this video and answer:

What is the main cause for global warming?
Why does it affect climate?
What climatic effects  can it cause?
How does it affect ecosystems. Tell examples 
Why can it cause floodings?
What happens when CO2 solves into water?

Video 2:

What does this video tell us about?
Batteries?
Drinking?
Burning plastics?
Plastic foams?
Appliances?

Chemical reactions 2ESO

Watch these videos and answer the questions 

Video 1

• What is a chemical proccess
• What examples of chemical reactions do they give us?
• What type of properties change during a chemical reaction. Give examples of each type
• Explain, using the film's words, what a chemical equation stands for

Video 2:

Watch and apply to balance these equations:

• N2 + O2 -> N2O5
• CH4 + O2 -> CO2 + H2O
• Li + O2 -> Li2O

Chemical reactions 4 ESO

Watch this films and answer the questions
Send the answers With "Formulario de contacto"

1. What examples of chemical reactions do you see in the video?
2. How does the rust reaction take place as explain by the candle?

In the second video

1. What does the scientist do with iron?
2. What is the cause for breathing, rust and Blood being red?
3. What does the balloon explode?
4. List several plenomena which May happen during a chemical reaction