Chemistry of Life: Atoms and Bonding

1. Chapter 6 NotesThe Chemistry of Life Section 6.1 Atoms and Their Interactions

2. Take 5: • ____________ is the condition that results from changes in the independent variable. • __________ results in an increase in the amount of living material and the formation of new structures.

3. Take 5 • An atom of Fluorine has nine electrons. Its second energy level has ________ electrons. • How many electrons can a carbon atom share? • What kind of bond is formed when two atoms share electrons, such as with hydrogen and oxygen in water?

4. Take 5 • Water dissolves many ionic and molecular compounds because of its __________. • Show the bond between magnesium and Sulfur. • Name two types of carbohydrates.

5. Take 5 • What are the two components of a lipid? • What are the 3 components of a nucleotide? • What do nucleotides make up? Give 2 examples….

6. Take 5 • Draw Neon and show the energy levels. • Show me a covalent bond between two carbon atoms. • Show me an ionic bond between NaCl

7. I. Elements • Natural elements in living things • Element= _________________________ ________________________________ • Four elements make up ______ of the mass of the human body: _________________ • Look at page 142, Table 6.1. It shows some common elements along with their symbols, found in the human body. A substance that can’t be broken down into simpler chemical substances. 9 6 % C, H, O , N

8. Elements in the Human Body

9. I. Elements • Trace Elements = ______________________________ ________________________________ (Table 6.1) Elements that play a vital role in maintaining healthy cells, but are needed in very small amounts

10. II. Atoms: The Building Blocks of Elements • Atom= the smallest particle of an __________ that has the characteristics of that element. • The structure of an atom • The center of an atom is the ___________. • The nucleus is made up of _________ (p+) which are positively charged and __________ (n) which are neutral or have no charge. Element Nucleus Protons Neutrons

11. II. Atoms: The Building Blocks of Elements 3. Elements are arranged on the Periodic table according to the number of ________ they naturally have. This number is called the __________ ____________. 4. The region of space surrounding the nucleus contains extremely small, negatively charged particles called __________ (e-). This region is also known as the __________ ___________. Protons Atomic Number Electrons Electron Cloud

12.  Atomic Number for Carbon= Therefore, there are 6 protons in the nucleus. 6

13. How many Protons are in the following Elements??? Helium Calcium Neon He = 2 Ca = 20 Ne = 10

15. II. Atoms: The Building Blocks of Elements • Electron energy levels (pg. 143, fig 6.2) 1. Within the electron cloud, there are energy levels which the electrons move in.

16. E1= 2 electrons E2= 8 electrons E3= 18 electrons E4= 32 electrons

17. Draw the energy levels of each atom: Nitrogen Iron (Fe)

18. III. Isotopes of an Element • Isotope = atoms of the same element that have the same number of ________, but a different number of ___________. • Scientists refer to isotopes by stating the combing total of ___________ and __________ in the nucleus. • For example: Carbon-12 (naturally occurring element) Carbon-14 (contains 2 more neutrons) - The nucleus is ___________ and tens to break apart and give off ______________. protons Neutrons protons Neutrons unstable radiation

20. IV. Compounds and Bonding • Compound = a substance that is composed of ________ of two or more __________ elements that are chemically combined. Ex: NaCl _______ • How and why do elements combine? _______________________________ ________________________________ • For many elements, an atom becomes ________ when its outermost energy • level is __________. atoms different Sodium Chloride Atoms combine with each other only when the resulting compound is more stable than the individual atoms. stable full

21. IV. Compounds and Bonding • How covalent bonds form • Covalent Bond = _____________________ • The electrons being shared ____________ around both elements holding them ___________ together • A ________________ is a group of atoms held together by covalent bonds. Ex: ____________ (_______) The force between two atoms that share electrons move close molecule H2 O water

22. IV. Compounds and Bonding • Examples of covalent bonds: a. Two hydrogen atoms

23. IV. Compounds and Bonding b. Two Carbon Atoms:

24. IV. Compounds and Bonding • How ionic form • Ionic bond= _______________________ ___________________________________ • Ion = ____________________________ • These bonds are ________ abundant in living things than covalent molecules, but ions are important in _________ processes • Examples of ionic bonds: The attractive force between two ions of opposite charge A charged atom that gained or lost electrons less biological

25. IV. Compounds and Bonding A. Table salt NaCl: B. MgS: Na = 11 Cl = 17 Mg = 12 S = 16

26. V. Chemical Reactions • Chemical reactions occur when ______ are formed or broken, causing substances to __________ into different substances. • All the chemical reactions that occur within an organism are referred to as that organism’s ________________. • Writing chemical equations • Basic Setup: _________ _________ Na+Cl  NaCl bonds recombine metabolism Reactants Products

27. V. Chemical Reactions 2. In chemical reactions, it is important to understand that atoms are neither _________ nor __________, they are simply rearranged. created destroyed

28. VI. Mixtures and Solutions • Mixture = a combination of substances in which the __________ components retain their own __________. Ex: _________________________ • Solution = a mixture in which one or more _________ (solutes) are distributed _________ in another substance (solvent). In other words, one substance is __________ in another and will not settle out of solution. • Ex: _____________________________ individual properties Mixing sand and sugar, salt and pepper substances evenly dissolved Sugar and water, food coloring and water

29. VI. Mixtures and Solutions • Acids and Bases • Chemical reactions can only occur when conditions are __________. One condition that is very important is the ____ of the solution. • The pH is a measure of how _________ or _________ a solution is. • Look on page 150, fig 6.11 for the pH scale ____________ is acidic, ________ is neutral, ________ is basic. • An acid is any substance that forms hydrogen ions (H+) in water. EX: _________________ right pH acidic basic 0 to 6 7 8-14 HCl  (H+) + (Cl-)

30. VI. Mixtures and Solutions 5. A base is any substance that forms hydroxide ions (OH-) in water EX: ___________________________ 6. If the hydrogen ions equal the hydroxide ions the solution is neutral and the pH of 7. 7. So…………… If H+ > OH- then solution is acidic If H+ < OH- then solution is basic If H+ = OH- then solution is neutral NaOH  (Na+) + (OH-)

31. pH of common substances

32. Concentration of H+ ions

33. Section 6.2 Water

34. I. Water and Its Importance • Water is polar • Polar Molecule= ____________________ __________________________________. • These molecules have a __________ end and a ______________. • Polar molecules attract other __________ molecules as well as _________ ________ • Look at page 153, fig 6.12. Water is a polar molecule. A molecule with unequal distribution of charge Positive negative polar Charged ions

36. I. Water and Its Importance • When two water molecules come in close contact, the negative ___________ end is attracted to the other water molecules positive ___________ end. This attractions of opposite charges forms a ________ bond called a ____________. • Because of water’s polarity, it….. • Is the ____________ ____________ • Can move up plants by ________ ________ oxygen hydrogen weak Hydrogen bond Universal solvent Capillary action

37. Water is a universal solvent!!!!!

38. I. Water and Its Importance • Water resists temperature changes • Water requires ______ heat to increase its temperature than other liquids. Why? ____________________________________________________________________ • When water cools, it gives _____ a lot of ___________. • Because water takes longer to heat up and cool down, it is like an _______ that helps maintain a __________ environment when conditions fluctuate outside and within our own ______________. more Because of the hydrogen bonds between each molecule. As you heat up water, the bonds must be broken to move around. off heat insulator steady Bodies/cells

39. I. Water and Its Importance • Water expands expends when it freezes - As water begins to _________ more and more _____________bonds are formed and the water molecules become more ________ apart. When this happens as a piece of ice forms, it becomes ________ ________ than the surrounding liquid water, therefore ice ___________________! freeze hydrogen spread Less dense floats

40. Just Know and understand the definition of Diffusion!!!!! II. Diffusion • Early observations: Brownian motion • (1827) Was one of the first to observe the random motion of molecules and substances. • The process of diffusion • Diffusion= ________________________ ___________________________________ • Diffusion is a ___________ process because it relies on the random _________ of atoms and molecules The net movement of particles from an area of higher concentration to an area of lower concentration. slow motion

41. Diffusion

42. Section 6.3 Life Substances

43. I. The role of Carbon in Organisms • Molecular Chains • Biomolecule = large ____________ compounds ( contains 10’s, 100’s, to 1000’s of carbon atoms) • Polymer = a large molecule formed when ________ smaller molecules bond together. organic many

44. I. The role of Carbon in Organisms • The structure of carbohydrates • Carbohydrate = a biomolecule composed of ________________________________ _____________________________ (C:H:O ratio) • Functions of carbos: ___________________ • Two types of carbohydrates: • _______________ • A _______________ is a ____________ (small) sugar • EX: glucose and fructose carbon, hydrogen, and oxygen that has or can be reduced to a 1:2:1 ratio Stores energy for the cell Sugars simple monosaccharide

45. I. The role of Carbon in Organisms Disaccharide • A __________ is _____ monosaccharide's linked together • EX: glucose + fructose = sucrose (table sugar)(pg 159, 6.17) • _______________ • Starches are ________________. The are polymers composed of many monosaccharide subunits. • EX: glycogen + cellulose (pg 159 6.17) 2 Starches polysaccharides

46. Carbohydrate- sugar Monosaccharide • Glucose is stored: • In a plant as starch • In an animal as glycogen The formula for glucose (C6H1206) is shown above. (1:2:1)

47. I. The role of Carbon in Organisms • Structure of Lipids • Lipid= large biomolecules that __________ ___________________________________ It can ______ reduced to a 1:2:1 ratio • The are _________ in water because their molecules are __________ and repel water • EX: _____________________________ ___________________________________ • Functions of lipids: __________________ __________________________________ are made mostly of carbon and hydrogen with a small amount of oxygen. not Insoluble nonpolar Fats, oils, waxes, and steriods energy storage, insulation, protective coverings

48. I. The role of Carbon in Organisms 5. Components of a lipid: a. ________________________ b. ___________________ (pg 160, 6.2) 6. Lipids can be saturated, unsaturated, or polyunsaturated. - Saturated = All of the ______ atoms are _______ bonded together; the molecule is now ____________ with hydrogen atoms Three fatty acids one glycerol molecule carbon Single saturated

49. I. The role of Carbon in Organisms • Unsaturated = when a _______ bond exists between two of the carbon atoms; the molecule now has ________ hydrogen atoms • Polyunsaturated = when _________ double bonds exist between the carbons; even __________ hydrogen is present now. • The structure of proteins • Protein= ________________________________ ___________________________________ double less many less A large, complex polymer composed of carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur.

50. I. The role of Carbon in Organisms • Components of a protein: __________ ___________________________ • The amino acids are linked together by covalent ___________ bonds. • Proteins come in a large variety of _______ and _________. The number and order of the ____________ determines its function. • Functions of proteins: a. Gives structure and ____________. Ex: _________ b. Help ____________ contact. Amino acids peptide shapes sizes Amino acids Hair, fingernails, horns, hoofs support muscles