TAMING THE TAKS TEST

1. TAMINGTHETAKSTEST

2. OBJECTIVE FOUR • Chemistry • Periodic Table (metals, nonmetals, noble gases) • Atoms and bonding atoms • Properties of Matter • Physical vs Chemical Changes • pH levels • Everything to know about WATER and SOLUTIONS

3. Color the Table like this picture Red, Green, Blue are METALS Yellow are NONMETALS Orange are NOBLE GASES

4. Groups/Families Vertical Columns (Up & Down) Elements share SIMILAR PROPERTIES because they have the same # of valence electrons (outer energy level) Periods Horizontal Rows (Side to Side) Elements are very DIFFERENT from each other What are Groups & Periods?

5. 3 Which of the following groups contains members with similar chemical reactivity? A Li, Be, C B Be, Mg, Sr C Sc, Y, Zr D C, N, O

6. 4 Basic Types of Elements • Metals: found on the left and center of the Table of Elements • Non-metals: found on the right side of the Table of Elements • Metalloids: found along the stair-step line • Synthetic: made in the laboratory and not yet found in nature – many of the Actinide and Lanthanide series and very large # elements.

7. Where are the metal elements? Left of the Stair-step line!

8. Properties of Elements - Metals • Metals are: • Conductors • Lustrous • Electron donors • Malleable • Ductile

9. Where are the nonmetals? To the Right of the stair step line, and Hydrogen!

10. Properties of Nonmetals • Nonmetals are brittle, insulators, electron acceptors • Usually form negative ions (except H) • Many are gases at room temperature • Found to the right of the stair-step line

11. Where are Noble Gases? Last column on the right! They are perfect!

12. Use the Table provided! What do the numbers mean? This is the atomic number. It is the number of protons in a single atom of this element. By the way, its also # of electrons. 11 Na The symbol for this element. This is the atomic mass, it is the number of protons + neutrons, or the mass of the nucleus of an atom. 22.990 sodium This is the name of the element.

13. Atoms are. . . • The smallest part of a single element. • The basis of all matter. • Made of mostly empty space. • Have a positive core or nucleus. • Have electrons in orbit in clouds.

14. The BOHR Model of an Atom • This is the first model to have a nucleus with protons and neutrons. • The electrons are in various energy levels and circle the nucleus. • Model most people draw today.

15. What are Valence Electrons • Every circle is an energy shell or orbit number • Each shell holds a certain number of electrons Shell # # of Electrons 1 2 2 8 3 18 MAGIC NUMBER TO REMEMBER IS 8 8 IS GREAT!

16. 23 According to the periodic table, which element most readily accepts electrons? • A Fluorine • B Nitrogen • This is a nonmetal, so it accepts electrons but it will also share them as in NO31-. • C Arsenic • This is a metalloid, so it only sometimes accepts electrons. • D Aluminum • This is a metal so it donates electrons. Fluorine only needs 1 electron to complete its shell of 8, so it will accept it from any other element very very very easily. This periodic property increases as you move up and left in the table, except for the Noble Gases.

17. Vocabulary • Compound - a pure substance composed of two or more elements whose composition is constant • Mixture - an aggregate of two or more substances that are not chemically united and that exist in no fixed proportion to each other. • Solution - such a substance, as dissolved sugar or salt in solution • Alloy - a substance composed of two or more metals, or of a metal or metals with a nonmetal, intimately mixed, as by fusion or electrodeposition.

18. Law of Conservation of Mass • Mass cannot be created or destroyed…its always there. • Ionic bonding • Covalent bonding

19. Names of Compounds – Ionic • Ionic compounds consist of cations (positive ions) and anions (negative ions). • A Roman numeral in parentheses, preceded by the name of the element, is used for elements that can form more than one positive ion. This is usually seen with metals. • Fe2+ Iron (II) Cu+ Copper (I)Fe3+ Iron (III) Cu2+ Copper (II)

20. Ionic compounds – naming cont. • The -ide ending is added to the name of a single element when it becomes an ion of that element. Oxide, Nitride, Sulfide etc. • Some polyatomic anions have a names ending in -ite for the lower # of oxygens and –ate for more oxygens. • NO2nitrite NO3nitrate

21. Covalent Compounds – Names are the Formulas • These are nonmetal to nonmetal compounds. • The name tells you the formula. Carbon dioxide 1 C and 2 O CO2

22. Bases end in the hydroxide anionOH- They are named with the metal and hydroxide. NaOH is sodium hydroxide Acids that are two elements are named Hydro-nonmetal –ic Acid such as HCl hydrochloric acid Group -ate becomes –ic and -ite becomes –ous. H2SO3 sulfurous acid H2SO4 sulfuric acid Special Names of Compounds Acids and Bases

23. 15 An advertisement claims that patients can be cured of the common cold in 48 hours by vitamin C tablets with secret mineral supplements. In a scientific experiment to test these claims, which data can be considered irrelevant? A The amount of vitamin C in each tablet B The severity of the patients’ cold symptoms C The chemical formula for vitamin C D The amount of time before symptoms improve

24. What doesn’t matter to the test? A The amount of vitamin C in each tablet This should be a controlled variable! B The severity of the patients’ cold symptoms This would be very hard to control, but a large experimental group should allow for differences C The chemical formula for vitamin C Compound formulas NEVER change so this is our answer it is irrelevant!!! D The amount of time before symptoms improve This is what we are testing, it is most relevant.

25. Matter • Anything that has mass and takes up space. • Energy is NOT matter

26. Matter is divided into 3 types: • Elements • Compounds • Mixtures

27. Pure Substances Elements are the simplest pure substances Mixtures are not pure substances and we will deal with them in a few minutes. The 3 types can be further separated in two categories: • Compounds which are formed when two or more elements share electrons or become ions that attract other elements.

28. Pure Substances Elements are the simplest pure substances Mixtures are not pure substances. Each part of a mixture keeps its own properties, and can be separated out by a physical change. The 3 types can be further separated in two categories: • Compounds which are formed when two or more elements share electrons or become ions that attract other elements.

29. P r o p e r t i e s o f M i x t u r e s : • E a c h s u b s t a n c e r e t a i n s i t s o w n p r o p e r t i e s . • S u b s t a n c e s c a n b e p r e s e n t i n a n y a m o u n t . • S u b s t a n c e s c a n b e s e p a r a t e d b y s i m p l e p h y s i c a l m e a n s.

30. There are two types of mixtures: • Heterogeneous- mixture is not the same from place to place. • Chocolate chip cookie, gravel, soil. • Homogeneous- same composition throughout. • Kool-aid, air, brass.

31. Decide if the substance is Element, Compound , or Mixture? 1. Water 1. Compound 2. Compound 2. Table Salt 3. Element 3. Oxygen 4. Mixture 4. Dirt 5. Mixture/Solution 5. Air Click Mouse button to see answers!

32. Let’s try a few more! 6. Copper 6. Element 7. Solution/Mixture 7. Soda 8. Solution/Mixture 8. Steel 9. Mixture 9. Rain 10. Mixture 10. Ice-cream Click Mouse button to see answers!

33. Other Properties of Matter • Density – the amount of matter in a given volume (diet coke vs coke) • Viscosity – resistance of fluid to flow (blood is thicker than water) • Buoyancy – tendency of a less dense substance to float in a more dense liquid (diet coke vs coke)

34. Density If you’ve ever carried bags of groceries, you know that some bags have greater mass than others, even though the volumes of the bags are the same. Mass and volume are general properties of all matter. Density is the ratio of mass to volume. The density of a specific kind of matter helps to identify it and to distinguish it from other kinds of matter. The unit for density of a liquids is grams per milliliter (g/mL).

35. The density of a piece of matter is a combination of how compressed the material is and how much its atoms or molecules mass per unit volume. Water has a greater density than steam because the atoms in a liquid are closer together than those in a gas. But iron is denser than ice, because the iron atoms are heavier than the water molecules, even though they both are solids.

36. Density is defined as the mass of a substance divided by its volume. The equation that is used for determining the density, D, of a substance is D = m/V, where m is the mass of the object, and V is its volume.More dense liquids will sink in the presence of less dense liquids.

37. As temperature is increased (or decreased) there is no change in the mass of an object. However, since substances generally expand as they are heated, the volume will increase with an increase in temperature. This increase in temperature will cause the density to decrease.

38. Density same on the Moon • Since density is related to the mass of an object, the density of a given volume of lead would be the same on both the Earth and the Moon, although the lead would weigh less on the Moon because of the lower gravity there.

39. Typically, when you freeze a liquid, its atoms or molecules get closer together, such that the solid is more dense than the liquid. An exception to this is when you freeze water. When ice is formed, it actually expands, thus making it less dense than water. After the temperature drops below -3 degrees C, the ice contracts and becomes more dense.

40. Viscosity Viscosity is a property that is often called on when liquids need to be classified. Each liquid has a different viscosity, or resistance to flow. Peanut butter has a much higher resistance to flow than milk, and thus it has a much higher viscosity than milk. We like ketchup that has a high viscosity. Likewise, motor oil is more viscous than gasoline.

41. The viscosity of motor oil is what allows the motor oil to stick to the metal parts of the engine. The weights given on motors oils ,S.A.E. values, correspond to "real" viscosity, taken at specific temperatures. Oils that fall into a certain range are designated 5, 10, 20, 30, 40, 50 by the S.A.E. The W means the oil is suitable for Winter use.

42. Viscosity is a measure of the ease with which molecules move past one another. • Viscosity depends on the attractive force between the molecules. • Viscosity decreases with increasing temperature - the increasing kinetic energy overcomes the attractive forces and molecules can more easily move past each other.

43. Viscosity also affects the shapes of lava flows and the mountains they erupt from. The more viscous the magma, the fatter the lava flow. Also, the more viscous the magma erupted, the steeper the volcano.

44. The viscosity of a given liquid is due to: • the shapes of the molecules • the attractive forces present between the molecules. • Substances with a high viscosity typically have both of these characteristics. The polar ends of the molecules attract each other, while the long structures of the molecules "get tangled" with other molecules. A viscous liquid is somewhat like a tank of snakes with each snake biting another snake’s tail, and each snake’s body wrapped around another snake’s body.

45. You may have heard that 90% of an iceberg lies below the water. Why is that? What determines whether something sinks or floats, and, if it floats, how much of it remains above the surface?

46. Buoyancy! Buoyancy is the tendency of an object to float in a fluid. It is controlled by differences in density between the object and the fluid. Buoyancy is summed up by Archimedes Principle: Any object, wholly or partly immersed in a fluid, is buoyed up by a force equal to the weight of the fluid displaced by the object.

47. People or objects that float are positively buoyant.Things that are too heavy and sink, they are negatively buoyant.Neutral buoyancy occurs when the force of gravity is balanced by the buoyant force. Divers want neutral buoyancy, a scuba diver does not want to float to the surface or sink to the bottom.

48. Two important forces are in play when Surfing: Buoyancy and Gravity:The water exerts its force on every part of the board that it touches.The weight of the surfer and board give a downward force due to gravity.

49. Three cubes of equal size are put in a fish tank. The left cube is made of stone, the middle cube is made of a plastic with equal density as water, the right cube is made of wood Positively buoyant Buoyant force Neutrally buoyant Negatively buoyant Force of Gravity

50. Whether an object floats or sinks, is based on not only its weight, but also the amount of water it displaces. That is why a very heavy ocean liner can float. It displaces a large amount of water.