Chapter 7 Slideshow

GRADE 8 SCIENCE UNIT 3: FLUIDS & VISCOSITY Chapter 7: Viscosity describes a fluid’s resistance to flow PTM... A REVIEW PG. 270 All matter is made up of very tiny particles. All particles in a pure substance are the same but different from another substance. There is space between the...

GRADE 8 SCIENCE UNIT 3: FLUIDS & VISCOSITY Chapter 7: Viscosity describes a fluid’s resistance to flow PTM... A REVIEW PG. 270 All matter is made up of very tiny particles. All particles in a pure substance are the same but different from another substance. There is space between the particles. The particles are always moving. They move faster if they gain energy. There are attractive forces between the particles. Some strong; some weak. CAN YOU IDENTIFY THE 3 STATES OF MATTER? 3 STATES OF MATTER... A REVIEW State Shape Volume Particle Particle arrangement movement 1. Solid Definite Definite Close Vibrate 2. Liquid Indefinite Definite Close Free flowing 3. Gas Indefinite indefinite Far Apart Random FLUIDS Any form of matter that flows. Since liquids and gases do NOT have a definite shape they are able to flow making them fluids. WE USE FLUIDS EVERYDAY. FOR EXAMPLE... Food fluids (water, oil, maple syrup, honey, etc) Cleaning fluids and creams Bodily fluids Industrial fluids (compressed air in tires, lubricants, etc) VISCOSITY A measure of a liquid’s resistance to flow. The thickness or thinness of a fluid. A fluid that is viscous is the one that is NOT “runny” (flows slowly). VISCOSITY & FRICTION? Friction resists movement. The greater the friction, the greater the viscosity. The particles are holding on tightly to each other. VISCOSITY IS IMPORTANT IN OUR EVERYDAY LIFE. FLOWRATE The speed at which a fluid flows from one point to another. Slow Medium Fast Corn syrup Dishwashing liquid Water Core Lab Activity 7-2 B pg. 282-3 THE FLOW RATE OF LIQUIDS  FACTORS THAT AFFECT VISCOSITY Temperature: As you increase temperature, you decrease a liquid’s viscosity. As you decrease temperature, you increase a liquid’s viscosity. The opposite is true of gases.  Concentration: The amount of a substance dissolved in a specific volume. Increasing the concentration, increases the viscosity.  Attractive Forces: If the attractive forces are strong, it is difficult for the particles to pull away thereby the fluid flows slowly and is more viscous.  Particle size: The smaller the particle size, the faster the fluid flows and is less viscous.