Mrs. Johnson Physical Science Behavior of Gases  Mrs. Johnson Physical Science

Measuring Gases When working with a gas it is helpful to know its volume , pressure and temperature. Volume is the amount of space that matter fills. Volume is measure in cubic centimeters (cm) , Liters (L) , and Milliliters (mL).  Because gas particles move and fill the space available the volume of a gas is the same as the volume of the container it fills.

Measuring gases Temperature is the measure of average energy of motion of the particles of matter. The faster the particles are moving the greater their energy and the higher the temperature. Particles in a gas move fast. Pressure of a gas is the force of its outward push divided by the area of the walls of the container. Pressure is measured in Pascals (Pa) or kilopascals (kPa). The firmness of a gas filled object comes from the pressure of the gas. Ex) basketball

Charle's Law French Scientist Jacques Charles examined the relationship between the temperature and volume of a gas that is kept at a constant pressure. He measure the volume of a gas at various temperatures in a container t5hat could change volume. When the temperature of a gas is increased at  a constant pressure , its volume increases. When the temperature of a gas is decreased at a constant pressure, its volume decreases. 

Boyle's Law Scientist Robert Boyle conducted experiments in an effort to improve air pumps. He measured the volume of gases at different pressures. His experiments showed that gas volume and pressure are related. When the pressure of a gas at a constant temperature is increased, the volume of the gas decreases. When the pressure is decreased the volume increases.

Pressure and Temperature When the temperature of a gas at constant pressure is increased, the pressure of the gas increases. When the temperature is decreased, the pressure of the gas decreases.

Graphing Charles law When a graph of a variable is a straight line passing through the origin, the variables are said to be directly proportional to each other. The graph of Charles Law shows the volume of a gas is directly proportional to its temperature under constant pressure.

Graphing boyle's law When the product of two variables is a constant, the variables are inversely proportional. The graph of Boyles law shows that gas pressure is inversely proportional to volume at a constant temperature.