1 Inorganic Chemistry

2 I.Matter A.Anything that has mass and takes up space. B.Matter exists in 3 states or phases: 1.Solid - have definite shape and volume 2.Liquid - have definite volume but shape depends on the container 3.Gas - both the shape and volume are determined by the container What makes the states different? Amount of kinetic energy- The kinetic energy of an object is the energy it possesses because of its motion

3 II. Atomic Structure A.The atom is the building block of matter. B.Subatomic particles make up atoms: 1.Electrons - have a “-” charge and no mass. 2.Protons have a “+” charge and a mass of 1 AMU (atomic mass unit). 3.Neutrons have no charge and a mass of 1 AMU (atomic mass unit).

4 Because of attraction to the positive nucleus. Fig. 2-1 Why do electrons stay In their “orbits”?

5 Atoms have a neutral charge. The electron(-) & proton(+) cancel each other out. Fig. 2-1 What is the charge of an atom?

6 II. Atomic structure (cont) C.When atoms gain or lose electrons then they are called “Ions.” ** What forms when a chlorine atom gains one electron? A chlorine ion (Cl - ) ** Magnesium loses two electrons? Mg +2

7 III. Periodic Table A.Displays all known chemical elements B.Atomic number = the # of protons 1.Each element has its own atomic number and if you add or remove protons you will have a different element.

8 C.Atomic Mass = #Protons + #neutrons. ** How many protons does Calcium (Ca) have? ** How many electrons are in a neutral atom of sodium (Na)? ** How many neutrons are in an atom of zinc (Zn)? = 65 #P + #N = Mass + #Nso 30 #N = 35

Isotopes and Radiation  Atoms of the same element that differ in the number of neutrons  Some isotopes are unstable and breakdown over a predictable period of time and give off radiation in the process

10 Isotopes have the same chemical properties because they have the same number of electrons! Fig. 2-2

11 Isotopes are identified by their mass numbers. Carbon has three isotopes: carbon-12, carbon-13, & carbon-14. Each has a different number of neutrons Fig. 2-2

12 IV.Chemical Bonding A.Molecules are formed by combining 2 or more atoms, e.g. O 2, or H 2 B.Compounds are molecules that form from combining 2 or more different elements, e.g. H 2 O or NaCl. Do compounds have the same properties as the elements that formed them? Think Water

13 IV. Chemical Bonding C. Chemical bonds are forces that hold two or more atoms together.

14 IV. Chemical Bonding D. Two types of Chemical bonds: 1.Ionic – 2 or more atoms exchange one or more electrons. a)Sodium loses an electron to become Na + b)Chlorine gains an electron to become Cl - c)Na+ and Cl- the compound sodium chloride (NaCl)

15 2.Covalent Bond – 2 or more atoms share electrons. covalent bonds are the most common in living systems.

16 3. Also we talk about Hydrogen “Bonding” - a weak force of attraction between H and O, F or N. Fig. 2-7 Water is a “polar” molecule

17 V. Chemical Reactions A.Chemical reactions occur when chemical bonds are being broken and reformed. B.All reactions either produce or use energy. C.The reactants (ingredients) are usually on the left D.The products are usually on the right. E.An arrow represents the progress of the reaction 2 H 2 + O > 2 H 2 O

18 VI. Water and its properties A.Hydrogen bonding is responsible for the following properties… 1.High surface tension What is this & How can it walk on water?

19 VI. Water and its properties 2.High specific heat capacity (its temperature is hard to change) and therefore: a)It’s a good coolant b)It’s a good antifreeze How much does the ocean temperature change during the year or in a day?

20 VI. Water and its properties 3. Water demonstrates capillarity (capillary action). Meniscus

21 Capillary action

22 VI. Water and its properties 4. Water has a high heat of fusion and vaporization (it takes a lot of heat to change the state of water… from solid to liquid and liquid to gas)

23 5. Most dense at 4°C (39.2 F). *** What impact does this have on life in a lake in the winter? B. Water is a universal solvent & a great lubricant. Coyote On Frozen Lake

24 VII.pH - “Potential of Hydrogen” A.pH scale Lower the number the more acidic (0-7) 2.Higher numbers are more basic or alkaline (7-14). 3.Neutral is 7. What is the pH of Water?

25 VII.pH - “Potential of Hydrogen” B.Definitions of an acid and a base 1.Acid - Proton donor (H + ) which lowers pH of a solution and taste sour. 2.Base (alkali) - Proton acceptor (OH - ) that raises pH of a solution and they taste bitter.