Name: _________________________________________

Notes: Atoms and the Periodic Table

Philosophy and Chemistry

• The ancient ____________________________ philosophers had _______ competing theories on _______________________________________________________________________________.

• _____________________________________ and Epicurus believed that matter was made of __________________________________ and _____________________________________ atoms.

• The word atom comes from the Greek Atomos, meaning ____________________________.

• __________________________________’s competing theory was that all matter was made of four elements: ______________, _______________, ______________, and _______________.

• An _____________________________ is a substance that can________ be broken down into a simpler substance.

• Given the ________________________________________________ and experimentation, Aristotle’s _________elements view was more widely ________________________ throughout Europe and the Mideast.

• This lead to a _____________________ year period sometimes called the ______________________________________________________________ because so ____________________________ was made in the field of ______________________.

• The focus was on ____________________________________________; the changing of one substance into another.

The End of Alchemy

• Eventually, chemists came to realize that matter was made of _______________________, small _______________________________________that still had all of the ____________________________and ____________________________________properties of their element.

• Many important experiments lead to this conclusion…. Such as:

o Robert Boyle’s _____________________________ of water experiment determined that water was NOT an element but a _____________________________________.

o Compounds are substances made of ________________________________________________ _____________________________________________________________________________.

o Robert Brown discovered ___________________________________________ – the ____________________________________________movement of tiny particles of pollen or powder in water due to the _________________________________________________________.

o This observation lead to the idea that atoms and molecules are constantly in _______________.

o The _________________________, discovered by Boyle, Charles, Amontons, and Avagadro, predicted how ________________________________________ affect the behavior of atoms:

________________________________, the amount of space taken up by a substance.

________________________________, a force created by the collisions of particles with a surface.

________________________________, the average kinetic energy of a substance.

________________________________, the number of particles in a container.

Up to this point, philosophers and scientists saw atoms as _________________________________________________________ that were ________________________.

This is sometimes referred to as the _____________________________________________________. Atoms are actually made of _________________________________________________, but other

experiments were needed to figure out what these particles were.

The Discovery of Electrons

J.J. _______________________________ was studying the ____________________ of ____________________________________ using ___________________________________________________________________ (CRTs).

• _____________ metal plates with different electrical ________________________ were placed on either end of a glass tube containing a vacuum.

This created a ___________________, called a ____________________________________________.

Thomson discovered that the particles of the cathode ray tube would respond to a ______________________________________.

A ______________________-charged magnet would ________________________ the beam. A ______________________-charged magnet would ________________________the beam.

Thomson discovered the first subatomic particle, _____________________________.

Thomson observed that when a small paddle ________________________ was placed in the path of the cathode rays, the wheel was set into ___________________________.

These experiments determined two important characteristics of ______________________________:

o They are _________________________________.

o They have ________________________________.

Thomson proposed that the electrons were ______________________________ in a ___________________________________-charged ___________________________ of matter.

This is named the __________________________________________________ of the atom, after the dessert it resembles.

The electrons are the ____________________________, and the positive matter is the ___________________.

Discovery of the Nucleus

Ernest ____________________________ was experimenting with __________________________, a radioactive element.

________________________________________________ atoms are _______________________ and __________________________________________________ over time, _________________________ _______________________________________________________________.

Ernest Rutherford used radium to direct a beam of tiny, ________________________ charged particles at a sheet of very thin _________________________________________.

Most of the particles passed directly ___________________________________the foil.

A few were partially __________________________________________.

Rutherford hypothesized that a small, ____________________________________________________ ___________________________________________________________________________________.

This area is now called the _______________________________________.

The positive particles within the nucleus are called _____________________________________.

Since most of the particles passed through the foil, it was concluded that atoms are mostly ___________________________________________.

Rutherford’s model of the atom had a ____________________________________________ surrounded by moving ___________________________________________.

Referred to as the “________________________________.”

The problem with this model was that the electrons often ____________ and ______________ ___________________, and according to this model, that would cause them to ______________________ into the _________________________________.

Neils ___________________________________ proposed that electrons only occupied __________________________________________________________, also called ________________________________.

Similar to rungs of a ladder. No electrons would appear between the “rungs”.

Electrons in orbitals __________________________ to the nucleus have the________________________ energy level, while electrons ______________________________ had the ___________________________.

Electrons are able to move _____________________________________________________________ _____________________________, called ________________________________________________.

Quantum jumps result in the _______________________________ or __________________________ of energy.

Jumping up to ________________________ energy levels requires the __________________________ of light energy.

Jumping down to _____________________ energy levels requires the __________________________ of light energy.

The light energy _____________________________________ and ____________________ by these quantum jumps creates a __________________________________, or combination of different ______________________________________________________________________.

Each ____________________________ has its own ___________________________________ that it produces when its electrons are ____________________________ (such as when burned in a flame).

Electron Cloud Model

The Bohr planetary model is inaccurate because electrons ____________________________________ __________________________________ around the atom in different-__________________________________________________________________, not just circles.

The ___________________________________________________________ of the atom shows all the ________________________________where electrons are the most likely to be found at any given moment.

History of the Periodic Table

Many scientists suspected a _________________________________ in the order of the elements, but were not able to exactly figure it out.

Dmitri _____________________________________________ was the first to create an accurate arrangement of the known ____________________________ based on the ________________________ of their ____________________________.

Mendeleev was actually able to ___________________________ the existence of elements that didn’t exist yet, based just on missing spaces in the patterns he saw on his periodic table.

Accurately predicted the actual properties of four of those undiscovered elements, including ________________________, scandium, technetium, and ________________________________.

The Periodic Table

The modern periodic table is a listing of all the _______________________________ in the universe, arranged by the _____________________________________________________________________.

o Each _______________ in the periodic table is called a __________________________.

o Each _______________ in the periodic table is called a __________________________.

Each element on the periodic table includes the same set of information:

The __________________________________________ indicates the ________________________________________________________________in the nucleus.

The __________________________________________ is one or two __________________ used to indicate the element as part of a ___________________________________________.

The __________________________________________ is its full name.

The __________________________________________ is the average mass of the atom in ___________________________________ ___________________________ (AMU).

The _______________________________________- gives the number of _______________________.

Oxygen has ______ protons.

If the atom is __________________________, it should have an _____________________number of __________________________ and ______________________________-.

Neutral oxygen has ____ electrons.

Since ______________________________________ and _______________________________ make up most of the element’s ________________, we can subtract the number of protons from the __________________________________________to find the number of neutrons.

________ – ____ = 8 neutrons in oxygen.

Calculate the number of protons, neutrons, and electrons in each of these elements:

Classification of Elements

Most of the elements in the periodic table are ______________________. Metals are:

___________________________________, meaning they can be _________________ into thin sheets.

___________________________________, meaning they can be ___________________ into thin wires.

___________________________________, meaning they can ________________________ heat and electricity well.

___________________________________________ occupy group __.

___________________________________________ occupy group __.

Alkali and alkaline earth metals are both considered __________________________________, because they ______________________________ form _________________________ with other elements are __________________ found in their ___________________________________ in nature.

_________________________________________ occupy groups __-____.

These are _____________________________________ and can be __________________ in their __________________________________.

Transition metals can be mixed together to form _________________________.

The metals to the ____________________ of the transition metals are called _____________________ ____________________________ because they are __________________ and easy to _______________, _____________________, and ___________________.

_________________________________________ include all of the metals in group 3, which stretches down below the periodic table.

_________________________________________________________ are actually not rare, just very __________________________________________________________________ from other metals when found in nature.

______________________________________________ don’t conduct heat or electricity, are ___________________________, and are often _____________ at ____________________________.

_______________________________occupy group ___.

Halogens are called __________________________________- because they easily react with ________________________ to form _________________________.

_______________________________ occupy group ___.

Noble gases are all ______________________ at ________________________________ and highly ______________________; they usually ______________________ with other elements.

_______________________________ share some properties with metals, and some with non-metals.

Metalloids include______________________, ___________________________, germanium, arsenic, antimony, tellurium, polonium, and astatine.

Ions

_________________are atoms that have _________________________________________________ ___________________________________________________________________________________.

Ions are written with either a ________________________________________ or _____________________________ sign next to their chemical symbol.

Positively-charged ions that have _________________________________ are called _____________________________________.

Negatively-charged ions that have _________________________________ are called _____________________________________.

How many electrons are present in each of these ions?

Br-

Mg2+

Al3+

S2-

Isotopes

While atoms within an element always have the ____________________________________________ ___________________________, their number of __________________________________________.

Atoms of the ___________________________________ with __________________________ numbers of __________________________ are called __________________________________.

Each isotope of an atom has a ____________________________________________________.

Chemists use __________________________________________________________________ to indicate what specific isotope of an element they’re working with.

The______________ form of isotope notation shows the _______________________________, _____________________________________________, and ________________________________:

The _________________________form writes out the element ___________________-, followed by the _________________________________.

Hydrogen, for example, has three isotopes. What would be the isotope notation for each?

Average Atomic Mass

To calculate the atomic mass of an element, chemists must determine the ________________________________________, or _________________________of a ___________________________ of an element sample that contains each isotope.

A given sample of hydrogen will have these relative abundances:

Hydrogen-1 has a relative abundance of 99.98%.

Hydrogen-2 has a relative abundance of 0.0184%.

Hydrogen-3 has a relative abundance of 0.0016%.

To find the average atomic mass, you ________________________ the ______________________________________________________ of each isotope by its _______________________________________________.

Make sure you use the percentages in ______________________________________. To do this, divide each by 100. For example, 99.98% / 100 = 0.9998

Hydrogen-1: 0.9998 x 1AMU = 0.9998 AMU

Hydrogen-2: 0.000184 x 2AMU = 0.000368 AMU

Hydrogen-3: 0.000016 x 3AMU = 0.000048 AMU

Add all three together, and you get the average atomic mass of hydrogen.

0.9998 AMU + 0.000368 AMU + 0.000048 AMU = 1.000216

The atomic mass of each element is written as a number with a decimal because it is an _______________________________ of all the known _________________________________of that element.

Radioactive Decay

The __________________________ of a nucleus depends on its ____________________________ of protons to neutrons in its nucleus.

If an atom has _____________________________________________, it can emit a ___________________________________________________________________ called a _____________________________________________.

This is the symbol for a beta particle:

β = −10 e

________________________________________________ converts a _____________________________ to a ___________________________________________, increasing the __________________________________________ by 1 and ____________________________________________________________________________.

Predict what will form when each of these atoms undergo beta decay:

If a nucleus has _________________________________ neutrons, it can __________________________ by emitting _______________________________________________ made of two protons and two neutrons.

This is the symbol for an alpha particle:

Alpha decay releases an __________________________________,____________________________ the atomic number by _____ and the atomic mass by _____.

Predict what will form when this atom undergoes beta decay:

Radioactive particles may also ______________________________- in the form of ______________________________________________ (γ).

This does not change the atomic number of mass of the atom, it just ________________________________________________.

__________________________ particles, being the _____________________________, can be blocked with a single _____________________________________________.

_________________________ particles can be blocked by a piece of_______________________, ___________________________, or a ____________________________________.

_________________________ rays can only be blocked if a thick enough wall is made of ___________________, ________________________________________, and _____________________________.

Any energy emitted from a source is called ________________________________________________.

Includes everything from _________________________________________ to __________________________________________-.

________________________________________ can strip electrons from atoms, creating ___________.

__________________________,____________________________ rays, __________________________________________, and ____________________________- particles are ionizing.

All other forms of radiation (______________________________, _____________________) are non-ionizing.