matter- atoms, elements and compounds… and you!! thanx to l. davinci

Matter- Atoms, Elements and

Compounds… and You!!

Thanx to L. DaVinci

First of all… What’sa Matter?

•Matter is anything that has mass and takes up space

•Everything in the observable universe is made of matter (as far as we know)

Thanx to http://abyss.uoregon.edu/~js/images/states_of_matter.gif

Name something that isn't matter: _______________

Draw each phase in the box:

How is a solid different from a liquid or gas or plasma? _____________

Atomic Structure:

Atomic nucleus contains protons (p+) and neutrons (n0)

-this makes up most of the atomic mass

electrons (e-) are outside nucleus; have very little mass

# of protons = # of electrons

If atoms are mostly empty space, how can they make up solid objects? Hmm

Atomic ModelsDalton (1803)- first atomic theory; solid sphere

J.J. Thompson (1897)- plum pudding model;Even distribution of + and – charges; discoveredthe electron!

Rutherford (1909)- planetary model; e- orbit a dense nucleus

Bohr (1913)- energy level model

Schrodinger (1927)- quantum mechanical Model; energy levels w uncertain orbits

Did you know…..If an electron weighed the same as a dime, a proton would weigh the same as a gallon of milk?

But…neutrons and protons have almost the same mass!

More Atom Fun…Atomic number= # of protonsMass number = # of protons

+ # of neutronsAtomic mass= average mass of one

atom (approx. equals the #p+ and n0)

http://mrbloch516.edublogs.org/files/2015/01/photo-oxygen-1l18wri.jpg

Even More…

Elements are neutralthe # of protons = # of electrons

How do you find the # of neutrons?

# of neutrons = mass number -# of protons

28

NiNickel58.71

2 8 16 2

+2

+1

+3

+4

Oxidation number

mass

How many protons?_____electrons?____ neutrons?____

Example….

Elements•Atoms make up elements•Elements are the simplest pure

substances (ex. Hydrogen, Helium, Oxygen); can’t be broken down by chemical means–92 naturally occurring; Earth’s crust is mostly Oxygen and Silicon

–The universe is mostly Hydrogen and Helium!

Chemical Symbols

•Give the symbol for each element below:

Carbon Helium NitrogenGold Silver LeadIron Potassium Neon

Isotopes (sound weird)

• An element always has the same # of p+ and e- but n0 may vary!– An element with a # of n0 outside the

norm is called an isotope– In this case, atomic # stays the same

BUT atomic mass changes

• ExAtom p+ e- n0 Atomic

mass12C 6 6 6 1214C 6 6 8 14238U 92 92 146 238235U 92 92 143 235