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Science Chapter 16 Booklet Solids, Liquids, and Gases Section One: Kinetic Theory Vocabulary: 1)  Kinetic theory: explanation of the behavior of molecules in matter; states that all matter is made of constantly moving particles that collide without losing energy   2)   Melting point: temperature at which a solid begins to liquefy 3)  Heat of fusion: amount of energy required to change a substance from the solid phase to the liquid phase   4)   Boiling point: the temperature at which the pressure of the vapor in the liquid is equal to the external pressure acting on the surface of the liquid 5)  Heat of vaporization: amount of energy required for the liquid at its boiling point to become a gas   6)   Diffusion: spreading of particles throughout a given volume until they are uniformly distributed 7)  Plasma: matter consisting of positive and negatively charged particles   8)   Thermal expansion: increase in the size of a substance when the temperature is increased Reading Check: 1)  Thermal energy id the total energy of a material’s particles.   2)   Temperature is the average kinetic energy of particles in a substance. That is how they are related. 3)  Heat of fusion is the amount of energy required to change a substance from the solid phase to the liquid phase.   4)   Liquids flow because they have more kinetic energy than solids. 5)  The external pressure must equal the pressure of the vapor in the liquid.   6)   At the first line the ice is melting at the second line the water is boiling or vaporizing so the temperature remains constant. 7)  Plasma is matter consisting of positively and negatively charge particles.   8)   Two examples of amorphous solids are glass and plastics. Picture Questions: 1)  The liquid state of water is the water in the pot and the solid state is the ice cube in the soup.   2)   Evaporation occurs below the liquids boiling point and boiling occurs at the liquids boiling point. 3)  The plasma phase is when something has positively and negatively charged particles so the overall object is neutral.   4)   Solid ice is less dense than liquid water so ice floats on water. Section One Review: 1)  List the three basic assumptions of the kinetic theory.   a)   all matter is composed if small particles(atoms, molecules or ions) b)  these particles are in random, constant motion   c)   these particles are colliding with each other and the walls of their container 2)  Describe the movement of the particles in solids, liquids, and gases.   a)   Particles in a solid are packed together tightly and are constantly vibrating in place. b)  Particles in a liquid are moving freely and have enough kinetic energy to slip out of the ordered arrangement of a solid.   c)   In gases, the particles are far apart and the attractive forces between the particles are overcome. Gases have no definite volume or shape. 3)  Describe the movement of the particles at the melting point of a substance.  A: The particles gain enough energy to slip out of their ordered arrangement.   4)   Describe the movement of the particles at the boiling point of a substance. A: Particles most have enough energy to equal the external pressure acting on the liquid. 5)  Think Critically. Would the boiling point of water be higher or lower on the top of a mountain peak? How would the boiling point be affected in a pressurized boiler system? Explain.  A: The boiling point would be higher because the pressure acting on it would be higher due to elevation. In a pressurized boiler system the boiling point would be lower because there would be pressure helping the liquid boil.   6)   Describe the energy changes that are occurring when water goes form -15 to 100 degrees Celsius. A: Water increases temperature, then stalls form 5 to 40 kJ of heat, then increasingly climbs, then stalling out again from 80 to 250 kJ of heat 7)  ?   Section 2~ Properties of Fluids  __ Vocabulary __ __ Buoyancy- __ the ability of a fluid- a liquid or a gas- to exert an upward force on an object immersed in it __ Pressure- __ force exerted per unit area, or P=F/A __ Viscosity- __ fluids resistance to flow __ Reading Check Questions __ When the weight of the water displaced-the buoyant force becomes equal to the weight of the ball, it floats. Weight of the water displaced is less than the rocks, so it sinks.       As the velocity of a fluid increases, the pressure exerted by the fluid decreases  Warmer temperatures have lower viscosity and cooler temperatures have higher viscosity __ Section Review __ Describe the two opposing forces that are acting on an object floating in water.  A: Buoyancy, Pressure  Explain how a heavy boat floats on water.  A: Density of boat and air is less than the density of water  Use Pascal’s principle to explain why squeezing a plastic mustard bottle forces mustard out the top. A: Because the pressure applied to the mustard is transmitted throughout the entire contents of the bottle pressuring it to the top. Describe, using Bernoulli ’s principle, how roofs are lifted off building in tornados. A. Viscosity of the tornados winds was greater than the air below it and the net force pushed the roof upward. If you fill a balloon with air, tie it off, and release it, it will fall to the floor. Why does it fall instead of float? What would happen if the balloon contained helium? A. Pressure is applied to the balloon where the net force pushes it downward; helium is less dense and therefore would float in the air. (120 x 9.8) = 1176 Buoyant Force 20000(.072) / 2.8= about 871.42 N __ Caption Questions __ 1. Explain why a boat that takes in water will sink. A: Because the density begins to equal out, sinking it. 2. Define Bernoulli ’s principle. A. As velocity of a fluid increase, the pressure exerted by the fluid decreases __ Applying Math __ F (2) = F (1) XA (2)/A (1) = 1500N X .80 / 25 = 48N Section 3- Behavior of Gases __ Vocabulary: __ Pascal – SI unit of pressure __ Reading Check __ forces cause collisions, particles increase, the area expands, and objects that can’t expand much have an increase in pressure Boyle ’s Law of Action Volume decrease as the temperature of the trapped gas decreases. __ Section 3 Review __ Explain why a gas has pressure A: Gas in smaller places, particles will strike the walls more often giving an increase pressure. Describe Earth’s atmosphere at sea level. How does the pressure change as the distance for Earth increases? A: At sea level there is noticeable pressure; distance form the Earth causes a less dense pressure. Explain using Boyle ’s law, the volume change of an inflated balloon that a diver takes to a pressure of 2 atoms. A: The pressure becomes greater than the balloon can hold and it explodes. Explain, using Charles ’s law, the purpose of gas burner on a hot-air balloon. A: Balloon walls have room to expand so instead of increased pressure, the volume increases. Labels on cylinders of compressed gases state the highest temperature to which the cylinder may be exposed. Give reason for this warning. A: If you place the cylinder above that temperature so the pressure becomes more than it can hold, which will cause it to explode. A: V (2)= 2X101/97=202/97= about 2.1 L A: 5/25 X n/30= 25n=150 15/25 n= 6 L __ Applying Math __ A: V (2)=98X11/86.2=1078/86.2= about 12.51 L  Science Stats 1. -269 + (-89) = 180 degrees Celsius 2. Rhenium, Osmium, Tantalum