Presentation on theme: "Chemical Bonding, Carbon style. Discover On the index card in your box, shade in a circle as dark as you can with your pencil. Take a piece of paper and."— Presentation transcript:
Discover On the index card in your box, shade in a circle as dark as you can with your pencil. Take a piece of paper and rub across this shading. What did you notice?
The Carbon Atom and Its Bonds The atomic number of carbon is 6 There are 6 protons in the nucleus and 6 electrons surrounding the nucleus. 4 of these electrons are valance meaning they are ready for bonding.
Chemical bonds are the force that hold two atoms together. A chemical bond between two atoms is made up of the atom’s valance electrons. Atoms of all elements (except noble gases) form chemical bonds. But few elements have the ability of Carbon to bond with both itself and other elements in so many different ways But few elements have the ability of Carbon to bond with both itself and other elements in so many different ways.
It is possible for carbon to arrange the same number of atoms in different ways. They can form straight chains, branched chains, and rings. Sometimes even networks of two or more rings of carbon atoms are joined together.
Forms of Pure Carbon Because of the ways carbon forms bonds, the pure element can exist in different ways. Diamond, graphite, and fullerene are three forms of the element Carbon.
Diamond The hardest mineral – diamond – forms deep within Earth. The hardest mineral – diamond – forms deep within Earth. At very high temperatures and pressures, carbon atoms for diamond crystals. Each carbon atom is bonded strongly to 4 other carbon atoms. At very high temperatures and pressures, carbon atoms for diamond crystals. Each carbon atom is bonded strongly to 4 other carbon atoms. The result is a solid that is extremely hard and unreactive. The result is a solid that is extremely hard and unreactive. The melting point of diamond is over 3,500 degrees Celsius. The melting point of diamond is over 3,500 degrees Celsius. They are formed in a crystalline pattern. They are formed in a crystalline pattern.
Graphite Every time you write with pencil you leave a layer of carbon on the paper. “lead” in the pencil is actually graphite, another form of the element carbon. It does not contain any of the element lead. Carbon atoms are bonded strongly together in flat layers. But the bonds connecting the layers are very weak, so the layers past by each other very easily.
Homework Questions 1. List three different forms of pure carbon. 2. What happens to valence electrons when a chemical bond forms between atoms? 3. How can you use differences in carbon bonds to explain why graphite and diamonds have different properties?
Organic Compounds Carbon Compounds are so numberous that they are given a special name. With some exceptions, a compound that contains carbon is called Organic Compounds. Organic means “of living things”. Any items that is made of from once living organisms is an Organic Compound. They can also be made artificially.
Hydrocarbons The simplest organic compounds are the hydrocarbons. A hydrocarbon is a compound that contains only the elements carbon and hydrogen.
Nutrients from Food Nutrients are substances that provide the energy and raw materials the body needs to grow, repair worn parts, and function properly. Most of the nutrients in food are organic compounds. Many nutrients are large, chain like molecules called polymers. Each link in the chain is a small molecule called a monomer.
The body can break apart the large molecules in food into smaller molecules. The process of breaking polymers into monomers, which involves chemical changes, has the familiar named digestion. After food is digested, the body then breaks apart some of the monomers, which releases energy. The body takes other monomers and reassembles them into polymers that match specific body chemistry
The four classes of polymers found in all living things are carbohydrates, lipids, proteins and nuclei acids.
carbohydrates A carbohydrate is an energy-rich organic compound made of the elements carbon, hydrogen, and oxygen. The word carbohydrate is made of two parts: Carbo and hydrate Carbo means “Carbon” and hydrate means “Combined with water” If you remember that water is made up of the elements hydrogen and oxygen, then you should be able to remember the three elements in carbohydrates.
Simple Carbohydrates The simplest carbohydrates are sugars. You may be surprised to learn that there are many different kinds of sugars. The sugar listed in baking recipes, which you can buy in bags or boxes at the grocery store, is only one kind. Other sugars are found naturally in fruits, milk, and some vegtables.
One of the most important sugars in your body is glucose. Its molecular formula is C 6 H 12 O 6. Glucose is sometimes called “blood sugar” because the body circulates glucose to all body parts through the blood. The name of the white sugar that sweetens cookies, candies, and many soft drinks is sucrose. It is a more complex molecule than glucose and has a molecular formula of C 12 H 22 O 11
Complex Carbohydrates When you eat plants or food products made from plants, you are often eating complex carbohydrates. Each molecule of a simple carbohydrate, or sugar, is relatively small compared to a molecule of complex carbohydrates. A complex carbohydrate is made of a long chain of simple carbohydrates bonded to each other. Just one molecule of a complex carbohydrate may have hundreds of carbon atoms.
Two of the complex carbohydrates assembled from glucose molecules are starch and cellulose. Starch and cellulose are both built from glucose monomers, but the monomers are arranged differently in each case. So starch and cellulose are different compounds. They serve different functions in the plants that form them. They body uses starch from foods very differently from the way it uses cellulose
Starch Plants store energy in the form of the complex carbohydrate starch. You can find starches in food products made from wheat grains, such as bread, cereal, and pasta. Starches are also found in rice, potatoes and other vegetables. The body digests the large starch molecules from these foods into individual glucose molecules. Then the body breaks apart the glucose and releases energy.
Cellulose Plants build strong stems and roots with the complex carbohydrate cellulose and other polymers. If you imagine yourself crunching on a stick of celery, you will be able to imagine what cellulose is like. Most fruits, vegetables, and nuts are high in cellulose. So are food products made from whole grains. Even though the body can break down starch, the body cannot break down cellulose into individual glucose molecules.
Therefore the body cannot use cellulose as a source of energy. In fact, when you eat foods with cellulose, the molecules pass right through you undigested. However, this undigested cellulose helps keep your digestive track active and healthy. Cellulose is sometimes called fiber.
Proteins If the proteins in your body suddenly disappeared you would not have much of a body left. Your muscles, hair, skin, and fingernails are all made of proteins. A bird’s feathers, a spider’s web, a fish’s scales, and the horns of a rhinoceros are also made of proteins.
Chains of Amino Acids The polymers called proteins are made of organic compounds called amino acids. That means that amino acids are the monomers in a protein molecule. Unlike the sugars in complex carbohydrates, the monomers in a protein are not exactly alike. In fact, there are 20 different kinds of amino acids.
Food Proteins Become Your Proteins Some of the best sources of protein include meat, fish, eggs and milk or milk products. Some plant products such as beans are good sources of protein as well. The body uses proteins from food to build and repair body parts. But the body must first break apart the protein polymers into monomers. Remember that starch in digested into individual glucose molecules. In the same way, proteins are digested into individual amino acids. The body reassembles those amino acids into thousands of protein
Lipids The third class of organic compounds in living things is lipids. Like carbohydrates, lipids are energy-rich polymers made of carbon, oxygen, and hydrogen. Lipids include fats, oils, waxes, and cholesterol. Gram for gram, lipids store more than twice as much energy as do carbohydrates. Lipids behave somewhat like hydrocarbons- the compounds of carbon and hydrogen. Lipids mix poorly with water.
Fats and Oils Fats are found in foods such as meat, butter, and cheese. Oils in foods include those such as corn oil, sunflower oil, peanut oil, and olive oil. Fats and oils have the same basic structure. Each fat or oil polymer is made of three fatty acid monomers and one alcohol monomer named glycerol. There is on main difference between fats and oils. Fats are usually solid at room temperature where as oils are liquid
Saturated and Unsaturated You may hear fats and oils described as saturated or unsaturated. Like saturated hydrocarbons, the fatty acids of saturated fats have no double bonds between carbon atoms. Unsaturated fatty acids are found in oils. Monounsaturated oils have fatty acids with one double bond. Polyunsaturated oils have fatty acids with many double bonds. Saturated fats end to have higher melting points that unsaturated.
Cholesterol Another important lipid is cholesterol, a waxy substance found in all animal cells. The body builds cell structures from cholesterol and uses it to form compounds that serve as chemical messengers. The body produces the cholesterol it needs from other nutrients. But foods that come from animals- cheese, eggs, and meat-also provide cholesterol. Foods from plant sources, such as vegetable oils, never contain cholesterol.
Vitamins: organic compounds that serve as helper molecules in a variety of chemical reactions in your body. Vitamin C or ascorbic acid, is important for keeping your skin and gums healthy. Vitamin D develops your bones and teeth and keep them strong. Minerals: elements needed by your body. Unlike other nutrients, minerals are not organic compounds. Common minerals are sodium, calcium, iorn, iodine, and potassium