The Air Around You Section 15 1 Composition

The Air Around You Section 15: 1

Composition of the Atmosphere Complete the following statement: The atmosphere consists 78% of what gas?

Composition of the Atmosphere • Nitrogen 78% • Oxygen 21% O O

Composition of the Atmosphere Neon • Other gases 1% Carbon Dioxide Helium Water Vapor Methane Ozone Argon Hydrogen

Composition of the Atmosphere

Properties of Air • Does take up space? • Paper Bag Test • Plastic Bottle and paper ball • Run with a sheet of paper

Properties of Air • Does air have mass? • How can we show that air does have mass?

Properties of Air Because air has mass it also has other properties including: https: //www. youtube. com/watch? v=TKMKKOV 7 xh. M Density = Mass Volume Pressure – force pushing on an area or surface

Measuring Air Pressure • Mercury Barometer – glass tube and a dish of mercury Pressure is measured by measuring the height of the mercury

Measuring Air Pressure • Aneroid Barometer – airtight chamber connected to a dial by a series of springs and levers

Measuring Air Pressure • Weather reports use several units for pressure Millimeters of mercury Inches of mercury Millibars 1 in = 33. 87 mb

Altitude and the Properties of Air • Altitude- Distance above sea level As altitude increases Air pressure decreases Lower air pressure Higher air pressure There is less weight of air molecules on you as you climb the mountain

Altitude and the Properties of Air • As air pressure decreases, so does density