CHANGES OF STATES: A PRESENTATION ON MATTERBY SPARSH GOYAL

SOLIDS TO LIQUIDS: MELTING

One of the most commonly known changes of matter is melting a solid to make a liquid. When a solid, say, an ice cube, heats up, it makes the particles of the solid start to vibrate more, like volume. Heat up, vibration up. When the solid is hot enough, the vibrations cause the bonds between the particles to “loosen” and the particles can move freely. When this happens, the ice cube melts and becomes water. The temperature which the solid melts at is called the melting point.

LIQUID TO SOLID: SOLIDIFYING

This is another well known change of matter. Solidification occurs when the heat energy is lost from the liquid, which lessens the vibrations of the particles, thus strengthening the bonds that are “loose” in the liquid particles. This creates the particle build-up of a solid, which means that the liquid has solidified into a solid. An example is metal. When you melt metal and put it in a mold, it will slowly take the mold’s shape, and will cool down, causing the bonds between particles to strengthen, therefor making the once liquid metal into a solid.

LIQUID TO GAS: EVAPORATION AND BOILING

This is a change that plays a key role in the water cycle. The liquid is given too much heat, starts to boil and finally, the particle bonds break, causing the particles to fly around everywhere. This creates an unstable structure for the particles, which makes gas, which takes no shape. The temperature which the liquid boils is called the boiling point.

GAS TO LIQUID: CONDENSATION

This is a change that happens when gas particles lose their energy, causing them to slow down and have the same particle structure as liquids, when the liquid particles are moving around slowly. This makes the gas change into liquid, thus condensing. You may have heard of condensation from the Water unit in 4th Grade.

SOLID TO GAS AND GAS TO SOLID: SUBLIMATION

This is a very uncommon change that takes place when a solid absorbs the heat energy and it goes directly to the gas state, skipping the melting, the liquid state and the boiling state. The same thing happens with gas to solid.

CITATIONS IN ORDER OF APPEARANCEIce 1: http://wotpast.wordpress.com/2012/07/02/motivate-me-day-two-melting-ice/

Ice 2: http://blogs.yis.ac.jp/19miyoshiay/2012/09/25/science-a-little-bit-of-matter/

Solidifying: http://yusufleinge.blogspot.sg/2013/08/goal-initiation-stage-solidifying.html

Evaporating: http://en.wikipedia.org/wiki/Evaporation

Boiling: http://en.wikipedia.org/wiki/Boiling_point

Condensation: http://en.wikipedia.org/wiki/Condensation

Sublimation: http://ed101.bu.edu/StudentDoc/Archives/ED101sp09/kortloff/Sublimation.html