Matter and Energy Chapter 4

Bell Work 11/3/10 1.Mass = 15 gvolume = 5 mL What is the density? 2.What is the volume?3. What is the volume?

Bell Work 11/9/10 1.Can an oxygen canister ever be half empty? Explain. 2.How does tea flavor spread from a tea bag throughout a cup of hot water? 3.What instrument is used to measure temperature?

4.1 Vocab Kinetic theory of matter – states that all of the particles that make up matter are constantly in motion

4.1 Vocab temperature – a measure of the average kinetic energy of all the particles in an object

4.1 Vocab thermometer – a device for measuring temperature degrees – evenly divided units of a temperature scale

Thermal Expansion All gases, many liquids, and most solids expand when their temperature increases.

Bell Work 11/8/10 For each description write which temperature scale it matches (Fahrenheit or Celsius) 1.Freezing point of water is 0 degrees 2.Freezing point of water is 32 degrees 3.Used by scientists and most countries units between freezing and boiling points of water

4.2 Vocab Heat – a flow of energy from an object at a higher temperature to an object at a lower temperature

4.2 Vocab thermal energy – the total amount of kinetic energy of particles in an object

4.2 Vocab calorie – the amount of energy needed to raise the temperature of 1 gram of water by 1 degree C joule – scientific unit for measuring energy (1 calorie = 4.18 joules)

Food Calorie One Calorie is actually one kilocalorie or 1000 calories One Calorie in food contains enough energy to raise the temperature of 1 kilogram of water by 1 degree C

4.2 Vocab specific heat – the amount of energy required to raise the temperature of one gram of a substance by one degree Celsius

Bell Work 11/9/09 Write the correct term for each definition. 1.The flow of energy from a warmer object to a cooler object. 2.The average kinetic energy of particles in an object. 3.The total kinetic energy of particles in an object. 4.The amount of energy required to raise the temperature of 1 gram of a substance by 1 degree Celcuis.

Energy moves as heat in three ways Conduction – moves energy from one object to another when they are physically touching Convection – energy is transferred in gases and liquids. Occurs when a warmer, less dense area of gas or liquid is pushed up by a cooler, more dense area of the gas or liquid. Radiation – energy travels across distances in the form of electromagnetic waves

Conduction Occurs any time that objects at different temperatures come in contact with each other Can also occur within a single object (spoon) Some materials transfer kinetic energy of particles better than others

Conductors – materials that transfer energy easily Insulators – materials that do not transfer energy easily or are poor conductors

Convection A cycle in nature responsible for most winds and ocean currents 1. cooler, denser air flows in underneath the warmer, less dense air, and pushes the warmer air upward 2. When this air cools, it becomes more dense than the warmer air beneath it 3. The cooled air sinks and moves under the warmer air

Radiation Energy that travels as electromagnetic waves Includes visible light, microwaves, and infrared light. Sun is the most significant source All objects, even humans, emit radiation and release energy to their surroundings Can move through empty space (Sun to Earth)

Bell Work 11/10/09 1.How many calories are needed to raise the temperature of 75 grams of water from 5 degrees Celsius to boiling? 2.How many calories are needed to raise the temperature of 50 grams of water from 30 degrees Celsius to boiling?

Bell Work 11/12/09 Answer the following questions imagining that a person is sitting in a chair in front of a fireplace. 1.What are two ways in which the person is warmed by the fire? 2.If a dog is sitting in between the person and the fireplace why might it be warmer where the dog is sitting? 3.Where in the room would conduction be most noticeable?

Bell Work 11/13/09 Please get out your study guide and review for the test.