# Cade an object is needed. Density is defined

Cade PatchellChemistryMrs. McCarrollJanuary 23, 2018IntroductionThe Cartesian diver has been known to scientists for hundreds of years. A Cartesian Diver is a science experiment named after the French scientist, René Descartes.He was born in 1596 and died in 1650. This experiment demonstrates the principles of buoyancy, Boyle’s law, density and the ideal gas law. An illustration of René Descartes, the inventor of the Cartesian Diver.ResearchThe principles of buoyancy, also known as Archimedes’ Principle, state that anything completely or partially submerged in a fluid (gas or liquid) is acted upon by a buoyant force. Density is why some objects float in a liquid and others sink. Water has a density of 1 g/cm3.  If an object floats in water, it means that it has a density less than  1 g/cm3. If an object sinks in water, it has a density greater than  1 g/cm3. The buoyancy of an object is its tendency to float on or rise in a liquid. An object that floats in water is positively buoyant, because it has a density less than the fluid it is floating in. An object that sinks is negatively buoyant, because it has a higher density than the fluid it is floating in. To determine an object’s buoyancy, the density of an object is needed. Density is defined as the mass of an object per unit volume. Density can be calculated by dividing the mass of an object by its volume. Density can be increased by decreasing the volume of an object. The three states of matter, solids, liquids and gases have different properties in terms of volume. Solids and liquids both have definite volumes, while gases do not. The particles of a solid are compacted and arranged in a pattern. The particles in a liquid are compacted but are not arranged in a pattern. The particles in a gas are not compacted, and are not arranged in a pattern. Pressure is defined as the continuous physical force exerted on or against an object by something in contact with it. In the mid 1600’s Robert Boyle studied the relationship between the pressure and the volume of a gas held at a constant temperature. Boyle’s Law describes the relationship between the pressure and volume of a fixed amount of gas at a constant temperature. The law shows that the product of the pressure and volume are observed to be nearly constant. The product of pressure and volume is defined as a constant for an ideal gas. The formula is pressure*volume = constant. There are some real-world examples of Boyle’s law. For example, when opening a bottle of soda quickly, sometimes it fizzes and shoots out of the bottle. This is due to the carbonation in sodas and changes in volume and pressure inside of the bottle. The ideal gas law states that the volume (V) occupied by n moles of any gas has a pressure (P) at temperature (T) in Kelvin.