1. An Introduction to Chemical Concepts Chemistry In this lesson, we will discuss the following: Chemical Size Properties Changes Naming Compounds

2. Click HERE if the web page at the right does not open. Let’s Do a Crossword Puzzle!

3. Categorizing Chemicals by Size SUBMICROSCOPIC: Anything which is too small to be seen with an optical microscope is considered to be submicroscopic. MICROSCOPIC: Anything that is too small to be seen with the naked eye but is large enough to be seen with an optical microscope is considered to be microscopic. MACROSCOPIC: Anything that is large enough to be seen with the naked eye is considered to be macroscopic.

4. Categorizing Chemicals by Size In chemistry, we will be discussing microscopic and submicroscopic particles, and how they affect what we see in the macroscopic world.

5. Properties We will discuss two kinds of properties: Physical Properties Chemical Properties

6. Physical Properties PHYSICAL PROPERTIES are defined as properties which can be observed without changing a substance into another substance (or group of substances). Examples of physical properties: Melting point Color Luster Hardness Texture

7. Chemical Properties CHEMICAL PROPERTIES are defined as properties that can be observed only by changing one substance into a new substance (or group of substances). Examples of chemical properties: Tendency to react with water Tendency to combust Tendency to decompose

8. Physical and chemical properties can be divided into two smaller categories: – Intensive properties and – Extensive properties. Click HERE to learn more about physical and chemical properties.

9. Click HERE if the web page at the right does not open.

10. Changes We will discuss two kinds of changes: Physical Changes Chemical Changes

11. Physical Changes A PHYSICAL CHANGE changes some characteristic (or characteristics) of a substance without actually changing what the substance is.

12. Chemical Changes A CHEMICAL CHANGE (or chemical reaction) is the change of a substance into a new substance (or group of substances). Click HERE to learn more about physical and chemical changes.

13. Click HERE if the web page at the right does not open.

14. Chemical Changes Click HERE if the web page at the right does not open. After the web page opens, click the green “Run Now!” button.

15. The atoms present before a chemical change are still present after the chemical change. The atoms are just rearranged to form new substances. This is called the Law of Conservation of Mass.

16. Chemical Changes Click HERE if the web page at the right does not open. After the web page opens, click the green “Run Now!” button.

17. Click HERE if the web page at the right does not open.

18. The transformation of oxygen, O 2, into ozone, O 3, is an example of A.a physical change. B.a chemical change. C.both a physical and chemical change. D.neither a physical nor chemical change. O=O O O O O O O oxygenozone

19. The transformation of oxygen, O 2, into ozone, O 3, is an example of A.a physical change. B.a chemical change. C.both a physical and chemical change. D.neither a physical nor chemical change. O=O O O O O O O oxygenozone

20. Elements Versus Compounds ELEMENTS: An element is defined as a substance made of only one kind of atom. COMPOUNDS: A compound is defined as a substance made of two or more kinds of atoms in a CHEMICAL combination. – A compound is made of elements, but a compound is uniquely different from the elements which make it up.

21. Click HERE if the web page at the right does not open. For help, click HERE.

22. Which of the following boxes contains an element? A compound? ABCABC A. Element: A, C Compound: A, B, C B. Element: CCompound: A, B C. Element: CCompound: B D. Element: A, CCompound: A, B

23. Which of the following boxes contains an element? A compound? ABCABC A. Element: A, C Compound: A, B, C B. Element: CCompound: A, B C. Element: CCompound: B D. Element: A, CCompound: A, B

24. Naming Compounds IONIC COMPOUNDS: An ionic compound is a substance made of a negatively-charged ion chemically combined with a positively-charged ion. – Many ionic compounds are made of one kind of metal ion and one kind of nonmetal ion. COVALENT COMPOUNDS: A covalent compound is a substance made of more than one nonmetal combined chemically. An ION is just an atom with a net charge.

25. Naming Type I Ionic Compounds A Type I ionic compound is made up of a metal and a nonmetal. Only metals which form ions with one charge take part in forming Type I ionic compounds.

26. Naming Type I Ionic Compounds In order to name a Type I ionic compound, you should do the following: 1.Write down the name of the metal atom first. The metal atom is farther left on the Periodic Table than the nonmetal atom. 2.Write down the name of the nonmetal atom next. Give the name an “ide” suffix.

27. Naming Type I Ionic Compounds Example: What is the name of LiBr? Solution: Lithium bromide Write down the name of the metal atom first. Next, write down the name of the nonmetal atom. Give the nonmetal the “ide” ending.

28. Click HERE if the web page at the right does not open. The web page at the right gives a little extra help with naming ionic compounds.

29. Naming Covalent Compounds A covalent compound is made of two or more nonmetals in a chemical combination.

30. Naming Covalent Compounds When naming a covalent compound, you should do the following: 1.Write the name of the first kind of atom in the chemical formula. Use the appropriate prefix if necessary. 2.Write the name of the second kind of atom in the chemical formula. Use the appropriate prefix if necessary, and use the “ide” suffix.

31. Some of the suffixes used when naming covalent compounds follow: – Mono = 1 – Di = 2 – Tri = 3 – Tetra = 4 – Penta = 5 – Hexa = 6 – Hepta = 7 – Octa = 8 Naming Covalent Compounds

32. The prefix “mono” should not be used with the first atom in a covalent compound. Naming Covalent Compounds

33. Example: Name the following compound: CO Naming Covalent Compounds Solution: Carbon monoxide Write down the name of the first atom. Use the appropriate prefix if necessary. Next, write down the name of the second atom. Give it the appropriate prefix if necessary and the “ide” ending.

34. Example: Name the following compound: CO 2 Naming Covalent Compounds Solution: Carbon dioxide Write down the name of the first atom. Use the appropriate prefix if necessary. Next, write down the name of the second atom. Give it the appropriate prefix if necessary and the “ide” ending.

35. Example: Name the following compounds: H 2 O and H 2 O 2 Naming Covalent Compounds Solution: Dihydrogen monoxide and Dihydrogen dioxide Write down the name of the first atom. Use the appropriate prefix if necessary. Next, write down the name of the second atom. Give it the appropriate prefix if necessary and the “ide” ending.

36. Sometimes Common Names are Used for Compounds Example: Name the following compounds: H 2 O and H 2 O 2 Or, they are called Water and Hydrogen peroxide

37. Click HERE if the web page at the right does not open. The web page at the right gives a little extra help with naming covalent compounds.