1. Warm-up #1
Use a sheet of notebook paper to do your daily warm-up. You will turn them in every few weeks.
175 kg = _________ g
Write in scientific notation
What things should be included in a graph.

2. Chapter 2 Notes
Chemistry Review

3. Matter
Is anything that has
mass and
takes up space
It is NOT-
ENERGY

4. There are 3 states of matter
Solid- molecules are very closely packed; definite shape and volume

5. There are 3 states of matter
Liquid-molecules have more energy and are further apart, indefinite shape but has a definite volume

6. There are 3 states of matter
Gas- most energy among molecules; take the shape of container and fills space available; indefinite shape and volume

7. Physical Changes
Changes in substances that involve changing states or simply cutting the substance in half are called physical changes

8. Chemical Changes
Changes that break chemical bonds and change the substance into another substance are known as chemical changes.

9. Is this a physical or chemical change?
Baking a cake
Cutting down a tree
Cooking chicken
Melting ice
Burning wood
Boiling water
Chemical
Physical
Chemical
Physical
Chemical
Physical

10. Atom Basic unit of matter: atom Protons with a positive charge
Electrons with a negative charge
Neutrons with a neutral charge/ no charge

11. Nucleus
Protons and neutrons are the two particles located in the nucleus, and they have a mass of 1 amu (atomic mass unit)

12. Electrons
Electrons are located around the nucleus in electron clouds- (NOT actually in rings!), and they have a negligible mass because they are hundreds of times smaller than protons and neutrons.

13. Elements Elements are pure substances made up of one kind of atom.
All atoms of that element look just the same, with the same number of protons, neutrons (average), and electrons.
The number of protons indicates the type of atom.

14. Elements Letters = a symbol for the element- representation
Atomic Number = Number of protons
Atomic Mass (weight) = mass of nucleus (# protons + # neutrons)

15. How many electrons are there?
The number of protons are the SAME as the number of electrons, which gives it a neutral charge
So how many electrons are in Cobalt? 27

16. Atom models
The protons and neutrons are drawn in the nucleus and the electrons around the nucleus in energy levels (rings)
You will learn how to draw atoms in Chemistry
Click photo to play video

17. Warm-up #2
In what state of matter do the molecules have the most energy?
What element has 24 protons?
What 2 parts make up the nucleus of an atom?
Are fireworks a physical or chemical change?

18. Sodium Atomic number Nucleus (protons + neutrons) Symbol Element
electrons
Atomic mass

19. How many _____ are in this picture?
Protons?
Neutrons?
Electrons?
What is the atomic number?
So what element is it? 6 6 6 6
Carbon

20. Ions
Ions are charged atoms with extra or fewer electrons than they have as an uncharged atom.
They gain or lose electrons in order to become stable.
A full electron level is considered stable.

21. Ions Would our Sodium atom gain or lose electrons to become stable?

22. Isotopes
Isotopes are uncharged atoms with a different atomic mass than the common element.
Count the number of neutrons in each isotope of carbon above

23. Isotopes
Some isotopes are radioactive and break down at a constant rate over time.
We can use these to help date rocks and fossils, use them to treat cancers, and use them as biological markers within an organism

24. Bonding
3 Types:
Ionic Bonds
Covalent Bonds
Hydrogen Bonds

25. Ionic Bonds electrons are transferred between a metal and a non-metal
strong force
examples: NaCl , CaS, MgCl2
Click photo to play video

26. Covalent Bond actually SHARE electrons between non-metals strong force
example: CO2, NO2
Click photo to play video

27. Hydrogen Bonds form between water molecules very weak force
We will discuss this in detail in 2.2 notes

28. Compounds A molecule is two or more atoms bonded together
Examples: O2 (oxygen gas), N2 (Nitrogen gas), Cl2 (Chlorine gas), O3 (ozone)
The physical and chemical properties of a molecule and compound are very different than the elements alone

29. Compounds
A compound is two or more atoms of different kinds bonded together in definite proportions.
 All compounds are molecules, but not all molecules are compounds 
Examples: H20, CO2, C6H12O6 (sugar)

30. Subscripts written below the level of line signify # atoms in molecule
if 1, then it is understood
Ex: 1 Mg atom + 2 Cl atoms  MgCl2
Polyatomic ions- group together as one written in parenthesis, you must multiply through, just like in math (order of operations!)

31. Subscripts Ex: Al(NO3)3 There is __ Al, __ N and __ O Ex: (CH3)3CH
There ___ C and ___ H 1 3 9 4 10

32. Coefficients written to the left of the molecule
signify # of molecules
Ex: 5NaCl 1 Na and 1 Cl in each molecule
5 molecules of NaCl
 10 total atoms.
Ex: 3 NO2 3 6
___ N and ___ O