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What is matter made of? Matter is made of molecules, which are made of atoms of the same or different elements. Atoms are the smallest particle that makes up an element. Escom.co.za carbon Elements are made up of only one kind of atom. can’t be broken down into other substances by any physical or chemical means. are chemical substances that make up all other substances. Molecules are made up of two or more atoms that are joined together chemically and act as a single unit have chemical bonds that hold the atoms together are so small that models are used to understand them Atoms and Molecules An element’s atoms are like the letters of the alphabet and molecules are like words. Most letters are combined with other letters to form words. Most atoms are combined with other atoms to form molecules. Some letters can’t be combined with other letters. Some atoms can’t be combined with other atoms. istockphoto.com How are atoms like letters and molecules like words? Write the letters A E O R S T in your notes. In two minutes, make as many words as you can using only these letters. You can use a letter more than once, but you can’t use any other letters than the six listed above. Answer the following questions in your notes: How many words did you make? Could you put the letters together in any order to make a word? In you groups, discuss how letters and atoms are alike. Be ready to share your answers. Atoms, Elements, Molecules and Compounds Hydrogen Cyanide Acetylene Ethane http://www.eso.org/public/events/astroevt/DeepImpact/images/di-mol.jpg Ammonia Compounds are made of two or more elements that are chemically combined can be broken down into simpler substances http://www.historyforkids.org/scienceforkids/chemistry/atoms/pictures/covalent.gif Compounds have different types of bonds Covalent: bond between two or more nonmetals Electrons are shared Examples: CH4 (methane) H20 (water) C12H22O11 (table sugar) C6H12O6 (glucose) Ionic: bond between metals and nonmetals Electrons are transferred Examples: NaCl (salt) MgO (magnesium oxide) CaCl2 (calcium chloride) Covalent Bond: electron sharing between two non metals Bohr model of a water molecule www.singularvortex.com/pictures/molecule_wate... Ionic Bond: electron transfer between a metal and a nonmetal A formula is a combination of symbols and small numbers to show what is in a compound. All compounds are molecules but not all molecules are compounds. H2, O2, N2, and Cl2 are molecules because they are made of only one type of atom. NO, H2O, NO2, and CO2 are molecules and compounds because they are made of more than one type of atom. Examples of Compounds Sugar: C12H22O11 Googleimages.com Compounds have unique properties By changing just one atom, the properties change and you have a new substance. H2O C2H5OH C6H5OH Mixtures Two or more substances that are in the same place, but not chemically combined. Examples: Trail Mix Sugar Water Orange Juice Sand Pure Substances made of only one kind of matter have definite properties every sample is always the same, no matter what the form include elements and compounds examples: Sugar: (C12H22O11) Salt: NaCl Water: H2O Iron: Fe Copper: Cu Share electrons Lose or gain electrons You could start really small... - Particles of matter - Atoms - Elements - Molecules - Macromolecules - Cell organelles - Cells - Tissues - Organs - Systems - Organisms - Populations - Ecosystems - Biospheres - Planets - Planetary Systems with Stars - Galaxies - The Universe ….And finish really big. Atoms Around Us If you want to have a language, you will need an alphabet. If you want to build proteins, you will need amino acids. Other examples in chemistry are not any different. If you want to build molecules, you will need elements. Each element is a little bit different from the rest. Those elements are the alphabet to the language of molecules. Why are we talking about elements? This is the section on atoms. Let's stretch the idea a bit. If you read a book, you will read a language. Letters make up that language. But what makes those letters possible? Ummm... Ink? Yes! You need ink to create the letters. And for each letter, it is the same type of ink. Confused? Don't be. Elements are like those letters. They have something in common. That's where atoms come in. All elements are made of atoms. While the atoms may have different weights and organization, they are all built in the same way. Electrons, protons, and neutrons make the universe go. If you want to do a little more thinking, start with particles of matter. Matter, the stuff around us, is used to create atoms. Atoms are used to create the elements. Elements are used to create molecules. It just goes on. Everything you see is built by using something else.