may think an object sinks or floats because an object is heavy or light. But not all heavy objects sink, and not all light objects float. For example, large ships are very heavy but they float. Also, a pound of feathers will float and a pound of bricks will sink.

Objects are made up of very tiny molecules. Objects with tightly packed molecules are more dense than those where the molecules are spread out. Density plays a part in why some things float and some sink. Objects that are more dense than water sink and those less dense float.

Substances A substance (eg oil, chocolate, styrofoam, wood) will float if it is less dense than water and sink if it is more dense than water. Objects An object will float if the volume of water it displaces weighs more than the object.

But why do things float or sink? The reason the pennies sink in water is because of an idea called density. The pennies have more density than the water, and so the pennies sink. Anything with more density than water will sink in water, but other objects that have less density than water will float.

Were you surprised to discover that a lot more drops of water fit on a penny than you predicted? We had 27 drops of water on ours! Surface tension and cohesion is the reason you can get so many drops of water on a penny. Cohesion is the “stickiness” of like molecules to one another.

Soapy water had the least surface tension. We were only able to get 11 drops of soapy water on the penny.

You should find that plain tap water produces a much larger, stable drop of water on top of the penny than the soapy water does. This is because plain tap water has higher surface tension, so the surface is “stronger” and can hold together a larger drop.

Even inhaling powerful fumes from soap products can impede breathing and cause life-threatening symptoms, so drinking it is obviously downright disastrous. In addition to burning your innards, it can cause you to vomit blood or pass blood through the other end of your before you potentially end altogether.