Chemical and Physical Changes

Chemical and physical changes occur in many ways. A few examples of chemical changes are burning and rusting. A few physical changes include breaking an object into smaller pieces. Another example of a physical change is melting. An object melts when too much energy is placed into a single object. These are just a few examples of a chemical or a physical change, but there are many ways to change an object. If you remove energy the object will freeze in position. If it is added the object may melt. These changes occur at exactly 0 degrees Celsius.

Chemical changes can occur in many ways. I my science class I had done many physical and chemical changes. For example, I put a marshmallow over a fire and roasted it. But a physical change can also be done with a marshmallow. I ripped a smaller marshmallow in half and tried both halves. The marshmallow was sweet and had a different texture but was very soft and easy to crush. These are examples of both physical and chemical changes.

BEFORE                                                AFTER



But marshmallows are not the only thing that can be burned. In class we burned another substance a little more common than marshmallows. In a test tube was placed two suger cubes. The test tube was placed over a Bunsen Burner until the sugar burned. Since only water can evaporate, the sugar lost all its water molecules turning the sugar into a new substance. This new substance is known as carbon.

There are many other changes I performed in my class as these are just a few of them. In class I also did an experiment where I used a gas to take out a candle. As the gas neared the fire it lost all of its oxygen because fire needs oxygen to survive. The fire went out as soon as the gas came close. The new gas vaporized into the air. All the oxygen was gone and the only substance left in the air was CO2 which caused the fire to blow out.                                       

This gas is the gas that had been used to take out a candle flame.