Matter and Energy #1

1. Matter and Energy #1 States/ Properties/Changes Forms & Transfer of Energy

2. Matter Section 1 • Anything that HAS MASS and they OCCUPY SPACE. • Ex? – List 5.

3. Kinetic Theory • Describes the behavior of matter • All matter is made of atoms and molecules that act like tiny particles. • These tiny particles are always in motion. The higher the temperature, the faster the particles move. • At the same temperature, the massive (heavier) particles move slower than the less massive (lighter) particles.

4. 4 States of Matter • There are 4 states of matter the kinetic theory helps describe: solids, liquids, gases and plasma. These states of matter are physically different.

5. Solid LEAST AMOUNT OF ENERGY • Molecules do not move freely, they vibrate in place, giving solids a rigid structure. • They have ordered, fixed, and tightly packed arrangements due to chemical bonding and intramolecular interactions

6. Liquids • Molecules are closer together and moves faster than solids. • Molecules are weakly attracted to one another moving less freely than gas. They move randomly and fill the container in which they are held. • The rate at which a liquid moves/flows is known as its viscosity. The slower moving= more viscous. Ex: Glass.

7. Gases • molecules are in constant, random motion spreading out in all directions (diffusion). • They exert pressure. The pressure is made by individual gas molecules hitting the sides of the container. • As the temperature rises, the molecules begin to move faster = the pressure increases • (the molecules hit the sides more often and with greater energy/force= increased pressure).

8. http://titanium.fullerton.edu/shock/PHASED.htm

9. Plasma MOST AMOUNT OF ENERGY • Usually an ionized gas. • Does not definite shape. • Conducts electricity well. • Effected by electric and magnetic fields.

10. http://www.harcourtschool.com/activity/states_of_matter/

11. Changes in State • Energy’s Role: required to move or change matter. Energy is transferred in all changes of state. • ENERGY REQUIRED- to melt or evaporate any substance. • Sublimation- physical change of a solid to gas- energy is required.

12. Changes in State cont. • Energy Released- during condensation. Gas → Liquid or Liquid → solid. • Changes of state: • solid → liquid → gas, does not change the composition or the mass.

14. Laws of Conservation • Law of Conservation of Matter: Matter cannot be created or destroyed. • Law of Conservation of Energy: Energy cannot be created or destroyed. (This is the 1st law of thermodynamics!)

15. Properties of Matter • Chemical Properties: how a substance reacts with other substances, chemically, to form new *** composition will be changed***substances. • Reactivity- the ability of a substance to react chemically with another substance. How much it will react depends on what they are reacting with and in what kind of environment the rxn is occurring. • Ex: rust (the ability of iron to react with oxygen), and combustion/flammability. Electronegativity, ionization potential, pH , heat of combustion, toxicity, stability, flammability…

16. Properties of Matter cont. • Physical Properties: characteristics of the substance which can be measured/observed without changing the composition of the substance. • Melting point- temp. @ which a solid becomes a liquid. • Boiling point- temp. @ which a liquid becomes a gas. • Density- the mass per unit volume. • Buoyancy- the force with which a more dense fluid pushes a less dense substance upward. * These properties help determine the use of the compound. *

17. Prop. Of Matter cont. • Chemical Changes: occurs when a substance changes composition to form a new substance. • Na2O + H2O→ 2NaOH • Combustion: CH4 + 2O2→ CO2 + 2H2O

18. Prop. Of Matter cont. • Physical Changes: only the physical properties/form change. The substance may look different but the atoms of the substance are not changed. • Ex: changes of state- solid to liquid to gas. The substance looks different but the composition remains the same (H2O is still H2O). • Grinding peanuts to make peanut butter. • Pounding a gold nugget to make a ring ** The melting point, density or color of gold doesn’t change**

19. Prop. Of Matter cont. • Melting, freezing and evaporation are physical changes. So is dissolving… • Ex: sugar water. The Sugar molecules are not changed… they only spread out in the water. Proof? The water still tastes sweet; thus, dissolving is a physical change.

20. Energy (heat) TransferA Review • Radiation- energy transfer through empty space. • No direct contact is required to transfer heat. • Conduction- heat transfer by DIRECT CONTACT • Convection- Heat transfer by the movement of a heated fluid.

21. Energy (heat) TransferA Review • Energy (heat) always transfers from HIGH to LOW. NEVER from low to high.

22. Conductors vs. Insulators • Conductor- matter which allow current/heat to flow. • Currents flow via ELECTRONS jumping from one atom to the next. http://www.ndt-ed.org/EducationResources/HighSchool/Electricity/conductorsinsulators.htm

23. Conductor

24. Insulator • Insulator- matter which resists the flow of current/ heat.

25. CALCULATING DENSITY • Which box would weigh more? Why? • The box that has more red balls (more mass per unit of volume). • This property of matter is called density. • Density is expressed in g/cm3.

26. CALCULATING DENSITY • The formula for calculating density is: • Solve: A piece of tin has a mass of 16.25g and a volume of 2.26 cm3. What is the density of the tin? • A man has a 50.0 cm3 bottle completely filled with 163g of a slimy green liquid. What is the density of the liquid? • A piece of metal has a density of 11.3 g/cm3 and a volume of 6.7cm3. What is the mass of the metal?