you are pouring out the carbon dioxide, which will sink and replace the (oxygen-containing) air surrounding the candle with carbon dioxide. It extinguishes the fire by creating suffocation. METHOD • Take the two candles and place them next to each other in the bowl. • Then pour in about 100ml of vinegar. Be careful you don't spill it as this stuff really smells! • Now it's time to light the candles. Make sure there is an adult around to help you do this. • Add half a tablespoon of bicarbonate of soda
It is the cohesive forces between liquid molecules are responsible for the occurrence of surface tension. The molecules at the surface do not have other like molecules that surround them and consequently they cohere stronger than those directly associated with them on the surface. This forms a surface "film" which make it more difficult to move the object through the surface than to moving it when it is completely submerged. Surface tension is measured in dynes/cm, dynes force required to
However, science is better defined as a way of observing and thinking about the world, and communicating these thoughts to others. Experience and research show that young children are excited about science when they are given the chance to "do" science. To give children a firm foundation in science they should be encouraged to think about and interact with the world around them. Concrete experiences that require the use of children's