I. ELEMENTS & ATOMS: Name: Period: Date:

Transcription

1 Name: Period: Date: I. ELEMENTS & ATOMS: = A substance that cannot be broken down into simpler substances o Periodic Table 1-92 occur in (natural elements) 93 and above are (man-made) Natural Elements: o are essential to living things o Carbon (C), Hydrogen (H), Oxygen (O), Nitrogen (N) make up 96% of human mass Trace Elements: o Found in very amounts but are to proper cellular activities o Ex: iron, magnesium, iodine = Smallest particle of an element that has the characteristics of that element o 3 Subatomic particles make up an atom: 1. (P) = charged particles 2. (N) = no charge ( ) 3. (e-) = ( charge) move nearly the speed of light form a cloud around the nucleus Nitrogen Atom o 2 parts of an atom: 1. = Center of atom; contains & 2. around the nucleus 1

2 II. ISOTOPES: = Atoms of the same element that have different numbers of o Named by their C-12 = ( + 6 P) C-13 = ( + 6 P) C-14= ( + 6 P) Radioactive (nuclei break apart) Used in the medical field III.ATOMIC NUMBER & ATOMIC MASS: = number of and/or of an atom Ex: Na-23 contains 11 electrons and 11 protons = the of protons and neutrons of an atom o IV.ENERGY LEVELS & DIAGRAMING ATOMS: = regions around the that electrons travel o 1 st energy level can ONLY have electrons Except Hydrogen; it has only 1 e- o = Each energy level AFTER the first can have up to electrons (2n 2 ) So 3 rd energy level has 18 e- (2 3 2 ) = 18 DIAGRAMING ATOMS: Ex: Helium (He) Atomic # = 2; Mass # = 4 Ex: Chlorine (Cl) Atomic # = 17; Mass # = 35 Nucleus 2

3 Ex: Carbon (C) Atomic # = 6; Mass # = 12 I. COMPOUNDS & BONDING: = a substance made of chemically combined elements. Atoms bond to form o Atoms need in OUTER energy level to be stable; Exception: hydrogen needs 2 e- Open bonding sites (electrons) encourage Elements can combine in two ways: 1. : o Covalent bonds electrons The positively charged nucleus is to the negatively charged electrons o Water, sugars, fats, and proteins are o = a group of covalently bonded atoms with charge Ex: H 2 O 2 hydrogen atoms + 1 oxygen atom 3

4 - Oxygen needs electrons to become stable - Each hydrogen needs electron to fill orbital Therefore, they!! 2. : o of electrons creating ions that attract each other = o = charged atoms because they have or electron(s) o Atoms that electrons become more o Atoms that electrons become more o Atoms gain/lose electrons efficiently 4

5 Ionic Bonding Na (11) e - 0 Cl (17) e - 0 Na loses 1e e ION Cl gains 1e e ION Na +1 + Cl -1 --> NaCl Na +1 + Cl -1 NaCl ~More effective to an electron than to an electron!! 5

6 II. WATER IS POLAR o = unequal distribution of charge o Each molecule has a end and a end o Ex: Water (H 2 O) molecule --> Oxygen is much stronger and therefore has a stronger than the hydrogen s positive charge o Because of water s polarity, it can many ionic compounds and other polar compounds such as o The water molecules also to each other because of (unequal distribution of charge) o The attraction of opposite charges forms a bond called a This keeps large molecules (Ex: proteins) III. UNIQUENESS OF WATER- due to its polarity! 1. The polarity of water cause the surface layer of water molecules to act like a stretched film over the surface of the water ( ) o Ex: water striders 2. The polarity of water allows to get water from the o Water creeps up tubes in plant roots and stems 3. Ice is dense than water (ice floats!) 6

7 I. CHEMICAL REACTIONS: All the chemical reactions in our bodies are called. - Breakdown and reassemble molecules in the body. Chemical reactions occur only when conditions are right: Temperature Availability of energy Concentrations of compounds ph of the environment How acidic/basic the environment is II. WRITING A CHEMICAL EQUATION: CH 4 + 2O 2 CO 2 + 2H 2 O (methane) + (oxygen) (carbon dioxide) + (water) = # of molecules of a compound Ex: 6O 2 = 6 molecules of Oxygen (O) 3H 2 O = molecules of H 2 O = # of atoms of an element Ex: CH 4 = 1 atom C, 4 atoms H CO 2 = atom of C, atoms O How many atoms of O are in 6O 2? atoms of O! III. BALANCING CHEMICAL EQUATIONS: In ALL chemical equations the number of atoms of elements are on the reactant and the product side of chemical equations o Why? Because of the (atoms are never created or destroyed; they are simply rearranged!) o We balance equations so the Law of Conservation of Mater is NOT! 7

8 o We must always balance equations using!! Tips for balancing equations: o can never be changed! o Coefficients must always be placed in of the entire compound! o Create an atom inventory Ex: Balance the following equations so the Law of Conservation of Matter is NOT violated: a) H 2 + O 2 H 2 O b) CaO + KBr K 2 O + CaBr 2 c) Al 2 S 3 + BaCl 2 AlCl 3 + BaS IV. ph, ACID, BASES: = how acidic or basic a substance is = substance that forms H + (hydrogen ions) in water H 2 O HCl H + + Cl - (ph than 7) = substance that forms OH - (hydroxide ions) in water H NaOH 2 O Na + + OH - (ph than 7) The ph scale:

9 Atomic Number and Mass Number Worksheet Name: Period: Date: Complete the following table. Also, properly label each nuclear symbol with the correct mass number. Nuclear Symbol Atomic Number Mass Number Number of Protons Number of Neutrons Number of Electrons Describe the 3 subatomic particles (charges and location) of an atom. 2. How are the atomic number and the number of protons related to each other? 9

10 3. How do the number of protons, number of neutrons, and the mass number relate to each other? 4. Draw the structure of a Nitrogen (N) atom (atomic number = 7; mass number = 14). Label the subatomic particles and nucleus. 5. Draw the structure of a Sodium (Na) atom (atomic number = 11; mass number = 23). Label the subatomic particles. 6. Draw the structure of an Aluminum (Al) atom (atomic number = 13; mass number = 27). Label the subatomic particles. 7. What is an isotope? What are isotopes named after? 8. What is the octet rule? 9. What is the difference between an atom and an element? 10

11 THE CHEMISTRY OF MATTER: ATOMS Name: Period: Date: PART 1: Structure of Atoms Atoms are composed of protons, electrons, and neutrons. The electrons carry a negative charge and are found in energy levels moving about the nucleus. The nucleus is made up of positively charged protons and neutrons, which have no electrical charge. The atomic number represents the number of protons and electrons. The mass number is the sum of protons and neutrons. All atoms need 8 electrons in their OUTER energy level in order to be stable (exception: hydrogen only needs 2 electrons in its outer energy level to be considered stable). Each of the diagrams below show an electrically neutral atom. Fill in the missing number of protons (p), neutrons (n), electrons (e) and mass number (M). Then complete the questions in the space below. e e e 2e 2e e p 10p 9p 6n n 10n M = 12 Carbon (C) M = 20 Neon (Ne) M = Fluorine (F) 1. Draw a box around the element that is most likely to bond with an element that can donate a single electron. Explain your choice. 2. Circle the element least likely to undergo a chemical reaction. Explain your choice. 3. A hydrogen atom has one electron in its outer energy level. Draw a triangle around the element most likely to form a compound with four hydrogen atoms. Explain your choice. The diagrams below depict different forms of carbon. Fill in the missing number of protons (p), neutrons (n), electrons (e), and the atomic mass (M). Then answer the qestions. M = 12 Carbon -12 e e e 2e e e 6p n M = Carbon -13 p 7n M = 14 Carbon What is the atomic number of carbon 12. Of carbon 14? 2. What is different in each of these atoms? 3. These different forms are all of carbon. 6p n 11

12 THE CHEMISTRY OF MATTER: BONDING PART 2: Bonding of Molecules The electrons in the outermost energy level of an atom determine the way in which the atom will form chemical bonds. If two atoms share one or more pairs of electrons, the bond is called covalent. If one atom loses electrons and the other gains elecgtrons, they from an ionic bond. All atoms need 8 electrons in their OUTER energy level in order to be stable (exception: hydrogen only needs 2 electrons in its outer energy level to be considered stable). Study this diagram, which represents a molecule of water. Then complete the following questions. 1. How many electrons are shared in this molecule?. 2. As part of this molecule, the outer energy level of each hydrogen atom has electrons and the outer energy level of the oxygen atom has electrons. Thus, hydrogen and oxygen atoms are considered. Oxygen (O) 4e 2e 8p 8n 4. What type of bond is this? 2e 2e 1p 0n 1p 0n Hydrogen (H) Hydrogen (H) The diagram below represents the state of two atoms AFTER they have undergone a chemical reaction to form a molecule. Study the diagram and answer the questions below. 1.What kind of bond is represented by A? 8e 2e 11p 12n A 8e 8e 2e 17p 18n 2. Why is the chlorine ion attracted to the sodium ion? 3. How many electrons were in the OUTER energy level of the sodium atom before the reaction? Sodium ion Na + Chlorine ion Cl - 4. How many electrons were in the OUTER energy level of the chlorine atom before the reaction. 12

13 Basic Chemistry Review Worksheet Name: Period: Date: Part 1: Vocabulary: Fill in the correct vocabulary word. Acid Atom Atomic mass number Atomic number Base Compound Covalent Coefficients Element Ion Ionic Isotopes Law of Conservation of Matter Nucleus Octet Rule ph Polar Subscripts 1. refers to the unequal distribution of charge of a molecule. 2. The states that each energy level AFTER the first can have up to eight electrons. 3. Any substance that forms H + (hydrogen ions) in water would be considered a(n). 4. How acidic or basic a substance is referred to as that substance s. 5. In a chemical equation, represent the number of molecules that are present. 6. Atoms of the same element that have different numbers of neutrons are called. 7. A substance that contains two or more elements that are chemically combined is called a(n). 8. A(n) substance that cannot be broken down into simpler substances. 9. A(n) bond occurs when there is a transferring of electrons between atoms. 10. Any substance that forms OH - (hydroxide ions) in water would be considered a(n). 11. The center of an atom is called the. 12. Charged atoms because they have gained or lost electron(s) are called. 13. Isotopes are named by their. 14. A(n) is the smallest particle of an element that has the characteristics of that element. 15. bonds occur when atoms of elements are sharing electrons. 16. In a chemical reaction, the number of atoms of an element are represented by. 17. The represents the number of protons and electrons that an atom contains. 18. Chemical equations must be balanced due to the. 13

14 Part 2: Concepts: Answer the following questions. 1. Describe the 3 subatomic particles (charges and locations) of an atom. Subatomic Particle Location Charge 2. In the following chemical equations, label the reactant(s), product(s) and the yields arrow. 2 KClO 3 2 KCl + 3 O 2 # of molecules of KClO 3 = # of atoms of K in 2KCl = # of atoms of O in 2 KClO 3 = 3. Draw a diagram of a phosphorous atom (atomic number = 15; mass number = 31). 4. List 3 ways of how water is a unique substance due to polarity. a. b. c. 5. Draw the ph scale. Include the correct numbers and locations of acids and bases. 6. Fill in each empty space in the table with the appropriate information. Nuclear Symbol Atomic Number Mass Number Number of Protons Number of Neutrons Number of Electrons

15 Unit Learning Map (17 days): Chemistry of Life Mrs. Sim Class: Biology A Unit Essential Question(s): How do chemical reactions impact living organisms? Optional Instructional Tools: Labs: - DUM-DUM chem - Soap tension lab - ph lab - Carbs. lab - McMush lab - Enzyme activity Concept Concept Concept Concept Atomic Structure Water Acids/Bases/pH Chemical Reactions Lesson Essential Questions: Lesson Essential Questions: Lesson Essential Questions: Lesson Essential Questions: How does an element s atomic structure affect its interactions with other elements? Why is water essential for all living organisms? How are acids and bases different? What happens in a chemical reaction? Vocabulary: Vocabulary: Vocabulary: Vocabulary: atom element compound proton neutron electron isotope mass number atomic number Energy level Octet rule ionic bond ion covalent bond Surface tension polar molecule ph scale acid base Reactants Yields Products Coefficients Subscripts Law of Conservation of Matter PA Standard: B : Describe and explain the chemical and structural basis of living organisms. 15

16 Chemistry of Life Vocabulary: 1) Element = A substance that cannot be broken down into simpler substances 2) Atom = Smallest particle of an element that has the characteristics of that element 3) Protons (P) = positively charged particles; found in nucleus 4) Neutrons (N) = no charge (neutral); found in nucleus 5) Electrons (e-) = (negative charge) move nearly the speed of light form a cloud around the nucleus 6) Nucleus = Center of atom; contains protons & neutrons 7) Electron cloud/energy levels around the nucleus 8) Isotopes = Atoms of the same element that have different numbers of neutrons; Named by their atomic mass numbers 9) Atomic Number = number of protons and/or electrons of an atom 10) Atomic Mass = the sum of protons and neutrons of an atom 11) Energy levels = regions around the nucleus that electrons travel 12) Octet Rule = Each energy level AFTER the first can have up to 8 electrons 13) Compound = a substance made of chemically combined elements. 14) Covalent Bonding = atoms SHARE electrons 15) Molecule = a group of covalently bonded atoms with no charge 16) Ionic Bonding = Transfer of electrons creating ions that attract each other = Ionic Bond 17) Ions = charged atoms because they have gained or lost electron(s) 18) Polar = unequal distribution of charge; Each molecule has a positive end and a negative end 19) surface tension = The polarity of water cause the surface layer of water molecules to act like a stretched film over the surface of the 20) Chemical Reactions: Reactants Yields Products CH 4 + 2O 2 CO 2 + 2H 2 O 21) Coefficients = # of molecules of a compound; Ex: 6O 2 = 6 molecules of Oxygen (O) 22) Subscripts = # of atoms of an element; Ex: CH 4 = 1 atom C, 4 atoms 23) Law of Conservation of Matter (atoms are never created or destroyed; they are simply rearranged!); We balance equations so the Law of Conservation of Mater is NOT violated! 24) ph = how acidic or basic a substance is 25) Acid = substance that forms H + (hydrogen ions) in water; (ph LESS than 7) 26) Base = substance that forms OH - (hydroxide ions) in water; (ph MORE than 7) 16