Wednesday, May 25, 2011

Check your understanding!!

1. Which of the following examples is a solid?
A. fruit juice B. cooking oil C. Oxygen D. sponge

2. The process in which cloud is formed is called.........
A. melting
B. freezing
C. condensation
D. evaporation

3You want to dry your wet hair quickly.Which of the following conditions will help you?You can stand......
A. under a moving fan
B. under a tree
C.in a dark room

condensation

The water droplets are formed when water vapour in the air turns into water as the side of the glass is cold.This process is called condensation.

Tuesday, May 24, 2011

Boiling and evaporation

When the water is heated,the water at the surface changed into water vapour.The process is called evaporation.

Boiling is a process that changes water into water vapour at a certain temparature.



freezing

If we put water in the freezer,the water will turn to ice.This process is called freezing.

Changing states

When ice is left at room temperature,it will slowly melt.This process is called melting.

Changing states

Matter is any substance in the universe,from smallest dust to the largest planet.It has mass and takes up space.It can exist in SOLID,LIQUID or GAS.


Solid~~~ if a solid is put into containers of different shapes,the solid does not take the shape of container. This shows that solid has fixed shape.

Liquid~~ When water is poured into various containers of different shapes,it will take up the shape of the container.This mean liquid does not have fixed shape.

Gas~~Most gases cannot been seen.They occupy space and have mass.An inflated balloon show the air occupies space.Gas has no fixed shape.The shape of gas depends on the shape of the container.

Saturday, May 21, 2011

Experiment!!!

Here's what you'll need:
• a big mixing bowl
• one 16-oz container of corn starch
• a measuring cup
• water
• scissors
• lots and lots of paper towels and a wet sponge for cleaning up!

Here's what to do:

1. Pour the dry cornstarch into the bowl.

2. Add about 1 1/2 cups of water.

3. Using your hands, mix the two together until it forms a thick paste. (You may have to add a little water — the mixture should have the consistency of tapioca pudding!)

4. Clear off the table around you and prepare to get a little messy!

5. Take some of the mystery matter in your hand and let it rest in your hand. (Make sure you hold it over the bowl!)

6. Next, grab a handful and give it a squeeze.

7. Let a handful rest in your hand. As some falls between your fingers, try cutting it with scissors.

8. Leave the mystery matter in the bowl and try poking it with your finger.


After the experiment,how can you force a physical change in matter? What happened to the state of the mystery matter when you took it out of the bowl and held it in your hand? What happened when you squeezed the mystery matter? What kind of energy was causing this change?
Before you try this , predict what state of matter (solid, liquid or gas) your mystery matter is when it is sitting in the bowl.
When you've finished , share your results with your friends. Based on your observations, what conclusions can you make about the state of your mystery matter? See what other tests you can come up with to prove your ideas.