Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Biosynthesis wikipedia , lookup
Biosequestration wikipedia , lookup
Evolution of metal ions in biological systems wikipedia , lookup
Microbial metabolism wikipedia , lookup
Oxidative phosphorylation wikipedia , lookup
Photosynthesis wikipedia , lookup
Photosynthetic reaction centre wikipedia , lookup
Isotopic labeling wikipedia , lookup
Interest Grabber Section 2-1 What’s the Matter? All of the materials around you are made up of matter. You are made up of matter, as are the chair you sit on and the air you breathe. 1. Give an example of solid matter. 2. Give an example of liquid matter. 3. Give an example of gaseous matter. 4. Is all matter visible? 5. Does all matter take up space? Go to Section: Section Outline Section 2-1 2–1 The Nature of Matter A. Atoms B. Elements and Isotopes 1. Isotopes 2. Radioactive Isotopes C. Chemical Compounds D. Chemical Bonds 1. Ionic Bonds 2. Covalent Bonds 3. Van der Waals Forces Go to Section: 2-1 The Nature of Matter Atoms •At Atom is the basic unit of matter. •There are 3 subatomic particles in an atom. They are called a proton, neutron and an electron. •The Nucleus of an atoms is the center of an atom and is made up of protons and neutrons. Go to Section: 2-1 The Nature of Matter Atoms Particle Charge Location in Atom Proton Positive Nucleus Neutron Neutral Nucleus Electron Negative Surrounding nucleus Go to Section: 2-1 The Nature of Matter Atoms Protons + Neutrons 0 electrons - Atoms have equal numbers of electrons and protons, and these subatomic particles have equal , but opposite charges Go to Section: An Element in the Periodic Table Section 2-1 6 Atomic number Element name C Carbon 12.011 Element symbol Mass number A chemical element is a pure substance that consists entirely of one type of atom. Go to Section: 2-1 The Nature of Matter Elements and Isotopes •An element’s atomic number represents the number of protons in an atom of the element. •An element’s mass number represents the number of protons and neutrons in an atoms of the element. •Isotopes are atoms of the same element that differ in the number of neutrons they contain. •Isotopes are identified by their mass number. •They have the same chemical properties because they have the same number of electrons. Go to Section: Figure 2-2 Isotopes of Carbon Section 2-1 Nonradioactive carbon-12 Nonradioactive carbon-13 6 electrons 6 protons 6 neutrons 6 electrons 6 protons 7 neutrons Go to Section: Radioactive carbon-14 6 electrons 6 protons 8 neutrons 2-1 The Nature of Matter Elements and Isotopes •A chemical compound is a substance formed by the chemical combination of 2 or more elements in definite proportions. •H20- 2 Hydrogen to 1 Oxygen •CO2- 1 Carbon to 2 Oxygen •NaCl- 1 Sodium to 1 Chlroine •C6H12O6-6 Carbon to 12 Hydrogen to 6 Oxygen Go to Section: 2-1 The Nature of Matter Chemical Bonds •Chemical bonds holds atoms in compounds together. •The 2 types of chemicals bonds are ionic and covalent •Ionic bonds form when one or more electrons are transferred from one atom to another. Go to Section: Figure 2-3 Ionic Bonding Section 2-1 Sodium atom (Na) Chlorine atom (Cl) Sodium ion (Na+) Chloride ion (Cl-) Transfer of electron Protons +11 Electrons -11 Charge 0 Go to Section: Protons +17 Electrons -17 Charge 0 Protons +11 Electrons -10 Charge +1 Protons +17 Electrons -18 Charge -1 Figure 2-3 Ionic Bonding Section 2-1 Sodium atom (Na) Chlorine atom (Cl) Transfer of electron Protons +11 Electrons -11 Charge 0 Protons +17 Electrons -17 Charge 0 Sodium ion (Na+) Protons +11 Electrons -10 Charge +1 Chloride ion (Cl-) Protons +17 Electrons -18 Charge -1 •An ion is an atoms that is positively or negatively charged because it has lost or gained electrons. •If it loses an electron it has a positive charge •If it gains an electron it has a negative charge Show video 2B Go to Section: 2-1 The Nature of Matter Chemical Bonds •Covalent bonds form when electrons are shared between atoms •A single bond is when atoms share 2 electrons •A double bond is when atoms share 4 electrons •A triple bond is when atoms share 6 electrons •A molecules is the structure that results when atoms are joined together by covalent bonds •Van der Waals forces are the slight attractions that develop between oppositely charged regions of nearby molecules. •Show video 2A and 2C Go to Section: Interest Grabber Section 2-2 Water, Water Everywhere If you have ever seen a photograph of Earth from space, you know that much of the planet is covered by water. Water makes life on Earth possible. If life as we know it exists on some other planet, water must be present to support that life. Go to Section: Interest Grabber continued Section 2-2 1. Working with a partner, make a list of ten things that have water in them. 2. Exchange your list for the list of another pair of students. Did your lists contain some of the same things? Did anything on the other list surprise you? 3. Did either list contain any living things? Go to Section: Section Outline Section 2-2 2–2 Properties of Water A. The Water Molecule 1. Polarity 2. Hydrogen Bonds B. Solutions and Suspensions 1. Solutions 2. Suspensions C. Acids, Bases, and pH 1. The pH Scale 2. Acids 3. Bases 4. Buffers Go to Section: 2-2 Properties of water The water molecule •Water is polar because there is an uneven distribution of electrons between the oxygen and hydrogen atoms. •Hydrogen has a slightly positive charge •Oxygen has a slightly negative charge. •The attraction between the hydrogen atoms of one water molecule and the oxygen molecule of another water molecule is an example of a hydrogen bond Go to Section: 2-2 Properties of water The water molecule The 3 properties of water are: 1. Cohesion: attraction between molecules of the same substance 2. Adhesion: attraction between molecules of different substances 3. Capillary action: movement through small spaces due to cohesion and adhesion Go to Section: 2-2 Properties of water Solutions and suspensions •A mixture is a material composed of 2 or more elements of compounds that are physically mixed together but not chemically combined. •The 2 types are solutions and suspensions •A solution is a mixture of 2 or more substances in which the molecules of the substances are evenly mixed •An example of a solution is saltwater. Go to Section: Figure 2-9 NaCI Solution Section 2-2 ClCl- Na+ Na+ Water Go to Section: Water Figure 2-9 NaCI Solution Section 2-2 ClCl- Na+ Na+ Water Go to Section: Water 2-2 Properties of water Substances in a solution Substance Definition Solute Substance that is Table salt dissolved Solvent Substance in which the solute dissolves Go to Section: Example in a saltwater solution water 2-2 Properties of water Solutions and suspensions •The greatest solvent in the world is water •A suspension is a mixture of water and nondissolved substances that are so small they do not settle out •An example is blood Go to Section: 2-2 Properties of water Acids, Bases and pH •An acid is any compound that forms H+ (positive hydrogen) ions in a solution. •A base is any compound that forms OH- (Negative hydroxide) ions in a solution. •A compound is neutral if it produces equal number of H+ and OH- ions. •Water is neutral •H2O↔H+ + OH•H+ + H2O ↔ H3O+ Go to Section: 2-2 Properties of water Acids, Bases and pH •Acids have a pH less than 7 •Bases have a pH greater than 7 •A neutral compound has a pH of 7 •Buffers are weak acids or bases that can react with strong acids and bases to prevent sharp, sudden changes in pH Go to Section: pH Scale Section 2-2 Increasingly Basic Oven cleaner Increasingly Acidic Neutral Go to Section: Bleach Ammonia solution Soap Sea water Human blood Pure water Milk Normal rainfall Acid rain Tomato juice Lemon juice Stomach acid Interest Grabber Section 2-3 Life’s Backbone Most of the compounds that make up living things contain carbon. In fact, carbon makes up the basic structure, or “backbone,” of these compounds. Each atom of carbon has four electrons in its outer energy level, which makes it possible for each carbon atom to form four bonds with other atoms. As a result, carbon atoms can form long chains. A huge number of different carbon compounds exist. Each compound has a different structure. For example, carbon chains can be straight or branching. Also, other kinds of atoms can be attached to the carbon chain. Go to Section: Interest Grabber continued Section 2-3 1. On a sheet of paper, make a list of at least ten things that contain carbon. 2. Working with a partner, review your list. If you think some things on your list contain only carbon, write “only carbon” next to them. 3. If you know other elements that are in any items on your list, write those elements next to them. Go to Section: Section Outline Section 2-3 2–3 Carbon Compounds A. B. C. D. E. F. Go to Section: The Chemistry of Carbon Macromolecules Carbohydrates Lipids Nucleic Acids Proteins 2-3 Carbon Compounds The chemistry of carbon •Carbon has 4 valence electrons •A carbon atom can bond to other carbon atoms so they can forms chains that can be almost unlimited in length. Go to Section: Figure 2-11 Carbon Compounds Section 2-3 Methane Go to Section: Acetylene Butadiene Benzene Isooctane 2-3 Carbon Compounds Macromolecules •Many of the molecules in living cells are so large that they are known as macromolecules •A monomer is a small unit that can join with other small units to form a polymer •Monomers join together to form polymers •This process is called polymerization Go to Section: Concept Map Section 2-3 Carbon Compounds 4 groups of organic compounds include Carbohydrates Lipids Nucleic acids Proteins that consist of that consist of that consist of that consist of Sugars and starches Fats and oils Nucleotides Amino Acids which contain which contain Carbon, hydrogen, oxygen Go to Section: Carbon, hydrogen, oxygen which contain which contain Carbon,hydrogen, oxygen, nitrogen, phosphorus Carbon, hydrogen,oxygen, nitrogen, 2-3 Carbon Compounds Carbohydrates •Made up of the element Carbon, Hydrogen and oxygen and are usually in a 1:2:1 ration •They are a main source of energy and structural. •The monomer is a monosaccharide •The three types of monosaccharides are glucose, fructose and galactose •Polysaccharides are large macromolecules formed from monosaccharides •The three are starch-plant storage cellulose-plant structure gylcogen –animal storage Go to Section: Figure 2-13 A Starch Section 2-3 Starch Glucose Go to Section: 2-3 Carbon Compounds Lipids •Lipids are mostly made up of the elements carbon, hydrogen and oxygen •The functions of lipids are store energy, serve as part of membranes, and waterproof covering. •Lipids are formed when glycerol combines with fatty acids •3 examples: fats, oils and waxes Go to Section: Lipids 2-3 Carbon Compounds Kind of lipid Description Saturated All fatty acid butter carbons are joined to another carbon by a single bond Unsaturated At least one carboncarbon double bond in a fatty acid Olive oil Polyunsaturated More than one c-c double bond in fatty acid Corn oil Go to Section: Example 2-3 Carbon Compounds Nucleic Acids •Made up of hydrogen, oxygen, nitrogen, carbon and phosphorus. •Their function is to store and transmit genetic information •They monomer is a nucleotide •3 parts to the nucleotide: nitrogenous base, phosphate group and 5-carbon sugar •2 types are : Ribonucleic Acid (RNA) and Deoxyribonucleic Acid (DNA) Go to Section: 2-3 Carbon Compounds Proteins •Proteins are made up of the elements: nitrogen, hydrogen, carbon and oxygen. •Their functions are control rate of reactions, transport substances in or out of cells, fight disease, and form bones and muscles. •Their monomer is the amino acid Go to Section: Figure 2-16 Amino Acids Section 2-3 Amino group Carboxyl group General structure Go to Section: Alanine Serine Figure 2-16 Amino Acids Section 2-3 Amino group Carboxyl group General structure Go to Section: Alanine Serine Figure 2-16 Amino Acids Section 2-3 Amino group Carboxyl group General structure Go to Section: Alanine Serine Figure 2-17 A Protein Section 2-3 Amino acids Go to Section: Interest Grabber Section 2-4 Matter and Energy Have you ever sat around a campfire or watched flames flicker in a fireplace? The burning of wood is a chemical reaction—a process that changes one set of chemicals into another set of chemicals. A chemical reaction always involves changes in chemical bonds that join atoms in compounds. The elements or compounds that enter into a chemical reaction are called reactants. The elements or compounds produced by a chemical reaction are called products. As wood burns, molecules of cellulose are broken down and combine with oxygen to form carbon dioxide and water vapor, and energy is released. Go to Section: Interest Grabber continued Section 2-4 1. What are the reactants when wood burns? 2. What are the products when wood burns? 3. What kinds of energy are given off when wood burns? 4. Wood doesn’t burn all by itself. What must you do to start a fire? What does this mean in terms of energy? 5. Once the fire gets started, it keeps burning. Why don’t you need to keep restarting the fire? Go to Section: Section Outline Section 2-4 2–4 Chemical Reactions and Enzymes A. Chemical Reactions B. Energy in Reactions 1. Energy Changes 2. Activation Energy C. Enzymes D. Enzyme Action 1. The Enzyme-Substrate Complex 2. Regulation of Enzyme Activity Go to Section: 2-4 Chemical reactions and enzymes Chemical reactions •A chemical reaction is a process that changes one set of chemicals into another set of chemicals by changing chemical bonds. •The reactants are the elements or compounds that enter into a chemical reaction •The products are the elements or compounds produced by a chemical reaction. •On notes label reactants and products Go to Section: 2-4 Chemical reactions and enzymes Energy in reactions •Energy is either released or absorbed when chemical bonds are formed or broken. •Activation energy is the energy needed to get a reaction started. Go to Section: Figure 2-19 Chemical Reactions Section 2-4 Energy-Absorbing Reaction Energy-Releasing Reaction Activation energy Products Activation energy Reactants Reactants Products Go to Section: Figure 2-19 Chemical Reactions Section 2-4 Energy-Absorbing Reaction Energy-Releasing Reaction Activation energy Products Activation energy Reactants Reactants Products Go to Section: 2-4 Chemical reactions and enzymes Enzymes •A catalyst is a substance that speeds up the rate of a chemical reaction •An enzyme is a protein that acts as a biological catalyst •Enzymes speed up reaction by lowering the activation energy of the chemical reaction •Show video 2D Go to Section: Effect of Enzymes Section 2-4 Reaction pathway without enzyme Activation energy without enzyme Reactants Reaction pathway with enzyme Activation energy with enzyme Products Go to Section: 2-4 Chemical reactions and enzymes Enzyme Action •Substrates are the reactants of enzymecatalyzed reactions •An active site is the site on the enzyme where the substrate binds. •The active site and substrates in an enzymecatalyzed reaction are often compared to a lock and key because the active site and substrate have complementary shapes and the fit is precise. Go to Section: Figure 2-21 Enzyme Action Section 2-4 Enzyme (hexokinase) Glucose Substrates Products ADP Glucose-6phosphate Products are released ATP Active site Enzyme-substrate complex Substrates are converted into products Go to Section: Substrates bind to enzyme Figure 2-21 Enzyme Action Section 2-4 Enzyme (hexokinase) Glucose Substrates Products ADP Glucose-6phosphate Products are released ATP Active site Enzyme-substrate complex Substrates are converted into products Go to Section: Substrates bind to enzyme Figure 2-21 Enzyme Action Section 2-4 Enzyme (hexokinase) Glucose Substrates Products ADP Glucose-6phosphate Products are released ATP Active site Enzyme-substrate complex Substrates are converted into products Go to Section: Substrates bind to enzyme Figure 2-21 Enzyme Action Section 2-4 Enzyme (hexokinase) Glucose Substrates Products ADP Glucose-6phosphate Products are released ATP Active site Enzyme-substrate complex Substrates are converted into products Go to Section: Substrates bind to enzyme Videos Click a hyperlink to choose a video. Atomic Structure Energy Levels and Ionic Bonding Covalent Bonding Enzymatic Reactions Video 1 Atomic Structure Click the image to play the video segment. Video 2 Energy Levels and Ionic Bonding Click the image to play the video segment. Video 3 Covalent Bonding Click the image to play the video segment. Video 4 Enzymatic Reactions Click the image to play the video segment. Go Online Career links on forensic scientists Interactive test Articles on organic chemistry For links on properties of water, go to www.SciLinks.org and enter the Web Code as follows: cbn-1022. For links on enzymes, go to www.SciLinks.org and enter the Web Code as follows: cbn-1024. Interest Grabber Answers 1. Give an example of solid matter. Sample answers: books, desks, chairs 2. Give an example of liquid matter. Sample answers: water, milk 3. Give an example of gaseous matter. Sample answers: air, helium in a balloon 4. Is all matter visible? No 5. Does all matter take up space? Yes Interest Grabber Answers 1. Working with a partner, make a list of ten things that have water in them. Possible answers: bodies of water, rain and snow, soft drinks and other beverages, juicy foods such as fruits, and so on. 2. Exchange your list for the list of another pair of students. Did your lists contain some of the same things? Did anything on the other list surprise you? Students’ answers will likely be similar, but not exactly alike. 3. Did either list contain any living things? Students’ lists may include plants, animals, or other living things. Interest Grabber Answers 1. On a sheet of paper, make a list of at least ten things that contain carbon. Students will likely know that charcoal and coal contain carbon. They may also list carbohydrates (starches and sugars), oil, gasoline, wood, or carbon dioxide. 2. Working with a partner, review your list. If you think some things on your list contain only carbon, write “only carbon” next to them. Students will say that charcoal and coal contain only carbon. While these materials do contain small amounts of other elements, such as sulfur, they are composed mostly of carbon. 3. If you know other elements that are in any items on your list, write those elements next to them. Students may know that many carbon compounds also contain oxygen and/or hydrogen. Interest Grabber Answers 1. What are the reactants when wood burns? Reactants are oxygen and cellulose. 2. What are the products when wood burns? Products are carbon dioxide and water. 3. What kinds of energy are given off when wood burns? Light and heat are given off. Some students may also mention sound (the crackling of a fire). 4. Wood doesn’t burn all by itself. What must you do to start a fire? What does this mean in terms of energy? To start a fire, you must light it with a match and kindling. You are giving the wood some energy in the form of heat. 5. Once the fire gets started, it keeps burning. Why don’t you need to keep restarting the fire? Once the fire gets going, it gives off enough heat to start more of the wood burning. This slide is intentionally blank.