Honors Biology Chapter 2

1. Honors Biology Chapter 2 Chemistry

2. DRY ERASE ATOM ATTITUDE • Everyone gets a dry erase board, dry erase pen, and tissue for erasing. • The teacher will ask you a question about atomic structure, you will write your answer and hold up your board.

3. Are you wondering why we are learning chemistry in biology class? • All of our cells are made of chemical compounds. • All the activities of our bodies work on chemical reactions. • All of our body’s reactions use water. Such as neurotransmitters affecting neurons

4. MATTER • Anything that occupies space (VOLUME) and has MASS • Is air matter? • Yes

5. Water Electricity Air Helium Sunlight Iron Carbon Matter Energy Matter Matter Energy Matter Matter Match as energy (capacity to do work) or matter (occupies space and has mass)

6. 2.1 ELEMENTS, ATOMS, COMPOUNDS (are matter)

8. YOU NEED TO KNOW • The Names (spelled correctly) and the Symbols (written correctly) on p. 18 (Table 2.1) • “Elements in the Human Body” • 25 elements (includes trace elements) • QUIZ on FRIDAY Sept. 27

9. ELEMENTS • Substance that cannot be broken down to other substances by ordinary chemical means (heating, adding an acid…) • YouTube - ?Tom Lehrer's The Elements" animated?? ****ASAP SCIENCE Periodic Table In Order OR YouTube - ?The Elements Animation??

10. Where can you find an element? The Periodic Table of the Elements – see Appendix 2 and get your personal copy

11. ELEMENTS AND SYMBOLS:Ca, H, Li, O, C, Mg • What rules apply to writing the symbols (abbreviations of the elements)? • First letter capital, second letter is lower case • What are the four most common elements in the human body? (see chart) • CHON • What are trace elements? • Less than 0.01% of human body weight

12. Which are elements? • Cu • C • CO • N • NO • WHY? • Cu C N only one kind of matter Gold - Au

13. COMPOUNDS • Substance of two or more different atoms chemically combined in a fixed ratio • EXAMPLES: CO2 • H2SO4 • H2O • CO • How is a compound written differently than an element? • More than one kind of element (more than one capital letter). • NOTE: H2 is not a compound – its an element • (Only one kind of element) Subscripts (tell how many atoms there are)

14. Formula • Formula is the abbreviation for a compound. • CO2 H2SO4 H2O • Carbon dioxide sulfuric acid water • What rules seem to apply to writing a formula? • Capital letters for elements • Subscript number behind and just below the line of what element it represents

15. Which are compounds? • Na N H2 NO2 H2O Why? • NO2 • H2O • 2 or more different elements chemically joined (2+ diff. capital letters)

16. Which are symbols?Abbreviations for elements • C CO2 Mn CO Ni Why? • C Mn Ni • Only one capital letter

17. What’s the difference? • Co CO co • Symbol formula nothing

18. Which are formulas?Abbreviation for a compound • H2SO4 Cl2 H20 Al Why? H2SO4 H20 abbreviations for compounds (2 or more different kinds of elements)

19. Can you figure out the difference between a mixture and a compound? • A mixtureis two or more elements (or compounds) NOT chemically joined. • A compound is two or more atoms chemically joined. • Do Worksheet: Elements, Compounds, Mixtures

20. DO WORKSHEET: Elements, Compounds, Mixtures • (back of Atomic Mass and Atomic Number Worksheet) • Work in groups of three, then we’ll compare answers.

21. 2.2 What are trace elements? • Needed in the body in only small amounts • Like mg (milligrams) • WHY IMPORTANT IF WE DON’T NEED SO MUCH? • Minerals act as catalysts (speed up reactions) for many biological reactions

22. Trace Elements Needed by some organisms but only in very small amounts Like iodine, we need only 0.15 mg per day A deficiency will cause a goiter

23. Trace Elements • Fluorine – in drinking water, toothpaste • (help dental decay) But too much can cause fluorosis (white chalky build-up)

24. Trace Elements • Iron Rich Foods • Most important use is to carry oxygen in the blood

25. 2.3 Atoms and Molecules

26. Atoms are made of protons, neutrons, electrons • Do you know what these particles are?

27. Answers: • Do you know what these particles are? Protons Neutrons Electrons

28. Basic Atomic Structure Youtube (1:57)

29. Atom • Smallest unit of matter that retains the properties of the element Li Na

30. Which shows one atom? • C N N2 H20 Why? • C and N • only one in number • Which are elements? • C N N2

31. Molecule • Two or more atoms held together by chemical bonds

32. Which are molecules? • Co CO CO2 O2 Why? • CO CO2 O2 two or more atoms (alike or not alike, it doesn’t matter) bonded together

33. Where is each subatomic particle located? • Proton in the • Neutron nucleus Electron-outside the nucleus • Golden Retrievers Show Atomic Structure Youtube (2:11)

34. What is the charge of each subatomic particle? • Proton Neutron Electron • + O _ • positive none negative

35. What is the relative size? • Proton neutron electron • 1 amu 1 amu ~1/1836 amu • AMU = atomic mass unit = 1/12 CARBON ATOM • (standard)

37. Neutral Atoms (no charge)(as seen on the periodic table) • 39 Mass Number p + n K Symbol • 19 Atomic Number p • (electrons = number of protons) • Neutral if negative charges = positive )

38. How can you tell the mass number and atomic number?

39. Atomic Number In order Identify element by its number of protons Mass Number A decimal (average of masses of all isotopes of that element) When looking on the periodic table…

40. Why is the mass number a decimal?Average of the Isotopes of Carbon • What is the mass number decimal? • 12.011 • What would you round it to? • 12

41. What is the atomic number of? • Silicon fluorine sodium WHY? • 14 9 11 • Number in succession (not a decimal) • Number of protons

42. What is the mass number of…? • Carbon nitrogen hydrogen • WHY? • 12 14 1 • Decimal number on periodic table • Not other number in succession • Number of p + n

43. How do you find the number of…? • Protonselectrons neutrons Atomic atomic mass number numbernumber minus atomic no. (if neutral)

44. How many? • Protons electrons neutrons • Carbon 6 6 6 • Chlorine • 17 17 18

45. What is the atomic number?Mass Number? • Number of p? • Number of e-? • Number of n?

46. Do Atomic Mass and Atomic Number WORKSHEET • Collaborate with your partner next to you, then we’ll see what’s right.

47. ISOTOPES INTRO • Isotopes (Virtual School) (2:51) • Watch the video and list what facts you learned about isotopes. • No, not about the Albuquerque Isotopes

48. Isotope • Atoms that differ in number of neutrons • Also differ in mass number(since it is p + n) • But all have the same number of protons

49. Isotope Examples • What are isotopes? (7:56)

50. Which is the most common isotope of Li? (check the periodic table)