Minggu, 09 Desember 2012

Changes In Materials

Reversible Changes
 A reversible change is when something can turn back into its original shape for example when ice is melted it turns into a liquid but then you can freeze it into a solid again do the change is reversible because it can change back into its original starter which is the ice in this case.

Irreversible Changes
A change is called irreversible if it cannot be changed back again. For example you cannot change a cake back into its ingredients again.
Irreversible changes are permanent. They cannot be undone.
In an irreversible change, new materials are always formed. Sometimes these new materials are useful to us. If you want to know more about reversible and irreversible changes, you can click: reversible and irreversible changes.

Rotting Of Wood
Wood rot is damage to wood caused by fungal colonies which settle on the wood and extend structures known as hypae into the substrate to take advantage of the nutrients and moisture in the wood. That is a conclusion about rotting of wood, you can click if you want to know more about the detail: rotting of wood.

Decomposition
Decomposition (or rotting) is the process by which organic substances are broken down into simpler forms of matter. The process is essential for recycling the finite matter that occupies physical space in the biome. Decomposition can be known more when you click this: decomposition.

Effects of Changes In Materials on the Environment
Some examples of the good effects are:
   *Return of Minerals, Water and Carbon Dioxide to the Earth
             When dead matter and animal waste decompose, minerals, water and carbon dioxide are returned  to the Earth. Decomposition also ensures that the Earth is not covered by dead matter and animal waste.
   *Creation of biodegradable material 
              When water and other substances are mixed, plant starch can be changed into a type of plastic called bioplastics. Unlike other types of plastics, bioplastics are biodegradable and thus unlikely to cuse harm to the environment.
Some examples of the bad effects are:
   *Air pollution
                Fuels releases harmful gases into the air which can cause air pollution. This can lead to health problems.
   *Damage to equipment
                All metals, with the exception of the precious metals, will oxidize when exposed to oxygen and an electrolyte. It is a chemical reaction of the metal surface with the oxygen present in the air that causes some of the metal to corrode.

I have a few experiments on changes in materials with my classmates; laksmi, reggy and jasper. the materials needed are: sugar, a spoon, a candle, butter, candle wax, a spoonful of flour, a beaker of water, a beaker half-filled with vinegar, a teaspoon of baking soda.
  Procedures:
1. Place some sugar in the spoon. Observe the appearance of the sugar.
2. Light the candle. Heat the sugar in the spoon over the candle flame until all the sugar has melted. Observe the appearance of the sugar.
3. Remove the candle flame. Leave the sugar in spoon to cool. Observe the appearance of the sugar.
4. Repeat steps 1 to 3, replacing sugar with butter.
5. Repeat steps 1 to 3, replacing sugar with candle wax.
  Here are some of the pictures:

                                  I held my hand holding the spoon with the sugar over to the candle.
                                                Look at the sugar started to be caramelized.