Go to Section: Matter –Anything that has mass and occupies space 1 The basic unit of matter is called the atom.

Go to Section: Nonradioactive carbon-12Nonradioactive carbon-13Radioactive carbon-14 6 electrons 6 protons 6 neutrons 6 electrons 6 protons 8 neutrons 6 electrons 6 protons 7 neutrons Section 2-1 Figure 2-2 Isotopes of Carbon 2, 3 Atomic Nuclei contain protons and neutrons. Protons1+ chargesize 1 amunucleus Neutrons0 charge size 1 amuin nucleus Electrons1- chargesize 1/1840 amuin electron cloud

Go to Section: 4 Atoms are neutral because they contain the same # of electrons & protons.

Go to Section: 5 Chemical elements are groups of atoms having the same atomic number, that is, atoms having the same number protons. These are all atoms of Carbon. All have atomic # 6.

Go to Section: 6 C Section 2-1 An Element in the Periodic Table 6. Proton # = 6 : shown by the atomic number Also, C atoms have 6 electrons: Since atoms are neutral, if you know proton #, you also know electron #!

Go to Section: Nonradioactive carbon-12Nonradioactive carbon-13Radioactive carbon-14 6 electrons 6 protons 6 neutrons 6 electrons 6 protons 8 neutrons 6 electrons 6 protons 7 neutrons Section 2-1 Figure 2-2 Isotopes of Carbon 7 Isotopes are forms of the same element that have the same number of protons but a different number of neutrons.

Go to Section: Nonradioactive carbon-12Nonradioactive carbon-13Radioactive carbon-14 6 electrons 6 protons 6 neutrons 6 electrons 6 protons 8 neutrons 6 electrons 6 protons 7 neutrons Section 2-1 Figure 2-2 Isotopes of Carbon 8Isotopes are identified by isotopic notation: Carbon-12, carbon-13, carbon-14 OR 12 C 13 C 14 C 6 6 6

Go to Section: 9 Isotopes of the same element have the same properties because they have the same atomic number (the same number protons) 12 C 13 C 14 C 6 6 6

Go to Section: 10 Chemical compounds are groups of atoms held together by chemical bonds. Chemical compounds are more stable than individual atoms (except for noble gas atoms which have stable ---filled— valence electron shells. Chemical compounds allow atoms to obey the “octet rule”. (2 electrons in the outer electron shell in H and He, but 8 for other elements.

Go to Section: 11 Chemical formulas show the numbers of different kinds of atoms bonded together in a single formula unit of a compound NaClone Na ion bonded to one Cl ion Why do we know it’s composed of ions? Because Na is a metal—an electron donor—and Cl is a nonmetal—an electron acceptor if a metal is present to give it an electron.

Go to Section: 12 Atoms in compounds are held together by chemical bonds—either ionic or covalent.

Go to Section: Sodium atom (Na) Chlorine atom (Cl) Sodium ion (Na + )Chloride ion (Cl - ) Transfer of electron Protons +11 Electrons -11 Charge 0 Protons +17 Electrons -17 Charge 0 Protons +11 Electrons -10 Charge +1 Protons +17 Electrons -18 Charge -1 Section 2-1 Figure 2-3 Ionic Bonding 13 Ionic bonds: attraction of negative ions to positive ions because a metal donates its electrons to a nonmetal atom, forming stable ions with complete valence shell octets.

Go to Section: 13 Covalent bonds form when nonmetal atoms share electrons to fill their valence octets, linking atoms because both nuclei attract the shared electrons.

Go to Section: Sodium atom (Na)Chlorine atom (Cl)Sodium ion (Na + )Chloride ion (Cl - ) Transfer of electron Protons +11 Electrons -11 Charge 0 Protons +17 Electrons -17 Charge 0 Protons +11 Electrons -10 Charge +1 Protons +17 Electrons -18 Charge -1 Section 2-1 Figure 2-3 Ionic Bonding 14 Ions are atoms carrying a charge after losing or gaining valence electrons.

Go to Section: 15. False. Atom that loses electrons becomes a positive ion.

Go to Section: 16 Molecules (Not ionic compounds!) form when atoms are joined with covalent bonds.

Go to Section: 17 A is false—2 shared electrons is a single covalent bond ACAC b D covalent bonds are formed when atoms share electrons

Go to Section: 18 Van Der Waals forces and dipole-dipole interactions hold atoms of nearby molecules together. Occasionally, valence electrons are nearer one atom than the other in a covalent bond, creating areas partial charge. sIMF/images/dipoledipole.jpg

Go to Section: Lesson 3: Chapter 2 The chemistry of Life 1.Watch movie on water, then answer questions on the worksheet together in your lab group BEFORE beginning the lab. Teacher will select one worksheet for grading, by random drawing. 2.Complete water lab, then turn in one copy per lab group. Teacher will select one student’s report. 3.Discuss the water movie & labs, and complete the 2.2 guided reading questions 1—8 as a class. Homework: guided reading & study workbook questions, pages 15—16, #9—21.

Go to Section: 2–2 Properties of Water, the strangest and most important molecule on earth! Section 2-2 Section Outline mages/wq_drop.jpg

Go to Section: mations/content/propertiesofwater/water.html Watch this movie from beginning to end. Then, the teacher will advance the movie one question at a time, giving time for you to write the answers to each question.

Go to Section: Guided reading & study workbook for section 2.2, p Water molecules contain 10 electrons, 1 for each H and eight for O. Water molecules also contain 10 protons True or False. Water molecules are neutral. 1.True 2.False

Go to Section: 2. Because water molecules have O at one end and H at the other, the entire molecule: 1.Is positively charged 2.Is negatively charged 3.Is polar, with partial + & - charges.

Go to Section: 3. Water is a polar covalent molecule because: 1.More electronegative O atoms are bonded to less electronegative H atoms 2.O carries a δ- charge & H’s a δ+ charge 3.The shared electrons of each O—H covalent bond are more strongly attracted to the O 4.All of the above 5.None of the above

Go to Section: Strongesttriple covalent bond 2nd strongestdouble covalent bond 3rd strongestsingle covalent bond 4 th strongestionic bond 5 th strongestHydrogen bonds 6 th strongestDipole dipole interactions (polar molecules attracted δ+ to δ- ) OTHER than Hydrogen bonds 7 th strongest Van der Waals forces (hydrophobic interactions of nonpolar compounds)

Go to Section: 4. Which statement is True? 1.Hydrogen bonds are stronger than ionic bonds. 2.Attraction of the H in one water molecule to O in another is a Hydrogen bond 3.Hydrogen bonds are stronger than covalent bonds 4.Hydrogen bonds are the strongest bonds BETWEEN different neutral molecules. 5.Choices 2 and 5 are true

Go to Section: cohesion

Go to Section: 5. Cohesion is: 1.Attraction of δ+ and δ- atoms of water molecules to atoms or ions of other substances, like the glass in a graduated cylinder 2.Attraction of δ+ H and δ- O of water molecules atoms in adjacent water molecules

Go to Section: 5. Adhesion (exhibited by water adhering to the spider web) is: 1.Attraction of δ+ and δ- atoms of water molecules to atoms or ions of other substances, like the glass in a graduated cylinder 2.Attraction of δ+ H and δ- O of water molecules atoms in adjacent water molecules

Go to Section: 6. Water is cohesive (shown by water’s forming droplets) because: 1.δ+ H and δ- O atoms of water molecules are attracted to each other in the same molecule 2.δ+ H and δ- O atoms of water molecules are attracted to each other in adjacent molecules

Go to Section: Surface tension versus capillary action

Go to Section: 7. The rise of water in a narrow tube (like water rising in a thermometer) against the force of gravity is: 1.surface tension 2. capillary action 3. specific heat

Go to Section: 8 In plants capillary action: 1.Draws water upwards from the roots into the leaves through thin tubes called xylem 2.Pulls sugar downwards from the leaves into the roots through thin tubes called phloem

Go to Section: Lesson on solutions and suspensions with homework correction slides Lesson on acids and bases Complete water labs & questions & acid/base questions. Tear off lab & questions through end page. Put rest back in notebooks. Homework: prep for a quiz on ch 2.1,2.2, tomorrow

Go to Section: Mixture: 2 or more substances combined but not chemically bonded. They can be separated without another chemical reaction (a physical separation). e.g., sand and water can be separated with a filter inks in markers can be separated with chromatography Salt can be removed from water by evaporating the water

Go to Section: 9. True or False. Sucrose (C 6 H 12 O 6 ) is a mixture. 1.True 2.False

Go to Section: 9. True or False. Sucrose (C 6 H 12 O 6 ) dissolved in water is a mixture. 1.True 2.False

Go to Section: Mixtures may be heterogenous (nonuniform throughout) or homogenous (uniform throughout) Another name for a homogeneous mixture is solution. Another name for a heterogeneous mixture is suspension.

Go to Section: 10. This picture shows bananas mashed up in water. This mixture is a 1.suspension 2.solution

Go to Section: 11. World’s greatest solvent: water! Water is known as the universal solvent because it can dissolve ionic compounds and polar covalent compounds. Ionic and polar covalent compounds are hydrophillic (water loving) Water can not dissolve nonpolar covalent compounds. Nonpolar compounds are hydrophobic (water hating)

Go to Section: 12. A suspension is a: 1.Homogeneous mixture 2.Heterogeneous mixture 3.Unstable (particles settle out over time) 4.Stable (a solution whose solutes do not settle out) 5.2 and 3

Go to Section: Parts of Solutions: Solvent: more abundant—does the dissolving Solute: less abundant—gets dissolved

Go to Section: 13. Two liters water are mixed with 0.3 liters salt. The water is the 1.solution 2.solute 3.solvent

Go to Section: 14. Two liters water are mixed with 0.3 liters salt. The salt is the 1.solution 2.solute 3.solvent

Go to Section: concentration Molarity (M) = # moles solute/#L solution 3 Moles/0.5 L = 6 M 1 mole NaCl = 58.4 g 29.2 g/0.25 L = 0.5 moles/0.25 L= 2M

Go to Section: Aqueous solutions can be neutral, acidic, or basic. These descriptions depend refer to the behavior of the solute when it is dissolved in water and to how this behavior alters the molar concentrations of these two ions in the aqueous solution: H + protons OH 1- hydroxide ions

Go to Section: 1 out of over 500 million water molecules dissociates to H + hydronium, OH - hydroxide Neutral aqueous solutions and pure water contain equal numbers of both ions. 2H 2 O (l) → H 3 O + (aq) + OH – (aq)

Go to Section: 14. Two water molecules can react to form: 2H 2 O (l) → H 3 O + (aq) + OH – (aq) 1.Nonpolar compounds 2.Hydronium & hydroxide ions

Go to Section: 15. Water is neutral because it: 1.Is polar covalent 2.Forms Hydrogen bonds 3.Has equal numbers of hydronium & hydroxide ions 4.Is nonpolar covalent

Go to Section: Acids increase the H 1+ content of water in aqueous solutions. Bases increase the OH 1- HCl  H + + Cl - NaOH  Na 1+ + OH 1-

Go to Section: Oven cleaner Bleach Ammonia solution Soap Sea water Human blood Pure water Milk Normal rainfall Acid rain Tomato juice Lemon juice Stomach acid Neutral Increasingly Basic Increasingly Acidic Section 2-2 pH Scale The more H + ions, the more acidic, the lower pH. The more OH 1- ions, the more basic, the higher pH. pH measures whether either H + ions are greater (acidic) or the OH 1- ions are greater (basic)

Go to Section: 16. The pH scale indicates: 1.The acidity of an aqueous solution 2.The basicity of an aqueous solution 3.The concentration of H+ ions present relative to concentration of the OH- ions 4.All of these.

Go to Section: 17. Which of these aqueous solutions is most acidic? 1.pH9 2.pH11 3.pH7 4.pH5 5.pH3

Go to Section: Oven cleaner Bleach Ammonia solution Soap Sea water Human blood Pure water Milk Normal rainfall Acid rain Tomato juice Lemon juice Stomach acid Neutral Increasingly Basic Increasingly Acidic Section 2-2 pH Scale pH 7 has 10 times less H+ than pH6 and 100 times less than pH5 The pH scale is logarithmic. So, pH 0 has 10 times more H+ than pH1 and 100 times more than pH2.

Go to Section: 18. How many more H+ ions does a solution with pH 4 have than one with pH 5? 1.1X more 2.10X more 3.100X more 4.It has 1X less than pH5

Go to Section: 19. Which statement is false? 1.Acidic solution pH is < 7 2.Acids add H+ to solutions 3.Strong acids make solutions whose pH is Acidic solutions have higher concentrations of H+ than pure water