atoms! ya can’t trust them, they make up everything!

Atoms!Ya can’t trust them, they make up everything!

Matter• Matter is anything that has mass and takes up space!• We have many different types of matter: pure substances, and mixtures.

• Law of Conservation of Matter – Matter can be neither created nor destroyed, merely transformed.

Most basic chemical - Atoms• Atoms are the smallest particles to have chemical properties.

• There are smaller particles, but they do not have chemical properties

• Atoms are made up of smaller particles called protons, neutrons, and electrons

• Different numbers of protons, neutrons and electrons determine an atom’s properties

Subatomic Particles

• Protons, Neutrons, and Electrons are called subatomic particles

because they are what make up atoms.

“Sub” meaning “within” or “beneath” the atom

Subatomic particles• Protons are:

• POSITIVELY CHARGED like the south end of a magnet

• BIG and GIVE the atom MASS

• They do not move within the atom

• They give the element its identity

• Neutrons are:

• NEUTRAL/HAVE NO CHARGE

• BIG and GIVE the atom MASS

• They do not move within the atom

• Stabilize the protons

Make up an atom’s nucleus

Subatomic particles (continued)• Electrons are:

• NEGATIVELY CHARGED like the north end of the magnet

• SMALL and DO NOT give the atom MASS

• Move rapidly around the nucleus

• Their movement is responsible for chemical reactions

Make up an atom’s electron cloud

Each atom has a nucleus made up of protons and neutrons

Each element has a unique number of protons

Properties of an atom

• Atomic number: the number of protons; it tells us which element the atom is for.

• Mass number: the number of protons plus the number of neutrons; how much the atom weighs.

• Charge: the positive charges plus the negative charges; if it is neutral, the number of protons is equal to the number of electrons

Atoms and Subatomic Particles• If an atom is neutral, the # of electrons equals the atomic number

• IF NEUTRAL: # electrons = # protons • If you are given an atom’s atomic mass #, you can calculate the

number of neutrons by subtracting the number of protons from this atomic mass #

• Mass # - Atomic # = # of Neutrons• If you have the # of neutrons you can add them to the # of protons

to discover the mass number• Atomic # + # of Neutrons = Mass #

Pure substances - Atoms• Pure substances contain only one type of particle (a unit of chemistry),

whether they are atoms or compounds

There are different types of atoms called elements.

• Each element has a different number of protons

• Each element has different characteristics from one another, especially associated with their class

Ions/ Isotopes

•Ions – atoms that have charge due to losing/gaining electron(s).

•Example: Na – electron = Na +1•Example: F + electron = Na -1

*Isotopes – atoms of the same element that have a different # of neutrons & mass.

12C6 = 6 protons & 6 neutrons vs. 13C6 = 6 protons & 7 neutrons

Periodic table

• Our periodic table directly tells us:

• The atomic number (how many protons)

• The average atomic mass (an average of all the atoms of that element)

• The symbol of the element

• The name of the element

Periodic Table

• Our periodic table tells us whether an element is a :

• a metal (to the left of the staircase)

• metalloid (touching the stair case)

• non-metal (to the right of the stair case)

• noble gas (the last column on the right)

**(These are classes of elements)

Metals

Metalloids

Non-metals

Noble gases

Pure Substances - Compounds

• When elements chemically bond together, they form a NEW UNIT of matter called a compound

• Compounds have different properties from the elements that make them up• Example, both hydrogen and oxygen support flame, yet, H2O (Water) puts out

flames!

Mixtures – a substance that contains 2 or more units of chemistry• Homogeneous –mixtures that are evenly distributed, even on the

atomic/molecular level

• Heterogeneous – mixtures that are not evenly distributed 100%, especially not on the atomic/molecular level.