Natural Chemical

Cycles and Acidification

Year 10 2015

The Water Cycle

The Carbon Cycle

Photosynthesis & Respiration

Photosynthesis

Water + Carbon dioxide Glucose + Oxygen

Water H2O Glucose C6H12O6

Carbon dioxide CO2 Oxygen O2

Write a formula equation and balance it if you can

Photosynthesis & Respiration

Respiration

Glucose + Oxygen Water + Carbon dioxide

Water H2O Glucose C6H12O6

Carbon dioxide CO2 Oxygen O2

Write a balanced formula equation.

Photosynthesis & Respiration

Photosynthesis

Respiration

The Nitrogen Cycle

What is pH?

• Every liquid you see will probably have either acidic or basic traits. Water (H2O) can be both an acid and a base, depending on how you look at it. It can be considered an acid in some reactions and a base in others.

• When you put molecules into water, sometimes they break down and release an H+ (hydrogen) ion.

• Somtimes, you find the release of an OH-(hydroxide) ion. When a hydrogen ion is released, the solution becomes acidic. When a hydroxide ion is released, the solution becomes basic. 

What is pH?

• Scientists use something called the pHscale to measure how acidic or basic a liquid is. Although there may be many types of ions in a solution, pH focuses on concentrations of hydrogen ions (H+) and hydroxide ions (OH-).

Effects of Atmospheric Carbon

Aim:

To observe the effect that increased levels of carbon dioxide has on the pH of water.

Results:

Colour after step 2: Acid or Base?

Colour after step 3: Acid or Base?

Effects of Atmospheric Carbon

PracticalMethod:

1. Put 50mL of water into a conical flask. To this add three drops of Bromothymol Blue indicator.

2. Add one drop of 0.1M Sodium Hydroxide solution and swirl the conical flask. Record the colour and state whether this solution is an acid or base.

3. Using the straw blow bubbles into the solution until a colour change is observed. Once again record the colour and state whether this solution is an acid or base.

Effects of Atmospheric Carbon

Discussion:

1. The acid formed in this experiment is called carbonic acid (H2CO3(aq)). Write both word and formula equations for this reaction.

2. After watching the ACE Science short of Ocean Acidification describe some effects which a more acidic ocean could have on marine animals and on humankind.

Conclusion:

Ocean Acidication

Acidification Video:

https://www.youtube.com/watch?v=Wo-bHt1bOsw

Environmental Chemistry Tasks 1 - 3

EC 1 EC 2 EC 3

Explain how nature recycles chemicals through processes like the carbon, water & nitrogen cycles.

Explain how nature recycles chemicals through processes like the carbon, water & nitrogen cycles. Explain what influences these cycles.

Explain how nature recycles chemicals through processes like the carbon, water & nitrogen cycles. Explain what influences these cycles, including human influence.

Draw a picture of TWO of the cycles including each of the main processes.Define the key terms in each cycle.

Draw a picture of TWO of the cycles including each of the main processes.Define the key terms in each cycle.Write a paragraph in your own words that details a major influence on the two cycles you have chosen.

Draw a picture of each of the cycles including each of the main processes.Define the key terms in each cycle.Write a paragraph in your own words that details a major human influence on the cycles.