Bushong Chapter 2

What are the properties of an electron?

- Small particles with negative charges - Atomic mass number of zero - Revolves around the nucleus in a defined orbit

What is an element?

An element is any quantity of identical atoms that combine to form a particular element

What is a radioisotope?

An isotope that undergoes radioactivity

Define nuclides.

Any nuclear arrangement

Define matter.

Anything that occupies space and has mass - The material substance that composes physical objects

Who improved Rutherford's nuclear model and in what year?

Neils Bohr in 1913.

Is mass the same as weight? Why or why not?

No, mass is not the same as weight because weight includes the gravitational pull on the object as well.

Define radionuclides.

Nuclides that undergo radioactive decay

What is the chemical symbol for Oxygen?

O

Radioactive atoms attempt to become stable through a process called _____.

Radioactive decay or radioactive disintegration

What is the chemical symbol for Rhenium?

Re

Define centripetal force.

The basic law of electricity that opposite charges attract and like charges repel

What does the nucleus of an atom contain?

The nucleons of the atom which make up most of the atoms mass.

What do the periods (rows) stand for in the periodic table? How many are there?

They stand for how many electron shells the atoms have and there are seven of them.

Describe the modern atom.

- It is based on Bohr's atom. - The nucleus is made up of protons and neutrons - Stable atoms have an equal number of protons and electrons - The arrangement of the electrons determines the manner in which the atoms interact - Atoms are mostly empty space - The nucleus is very and orbits of the electrons are very wide

What are the characteristics of atomic mass numbers?

- They are an estimated unit of measurement of atomic particles - They are rounded to the nearest whole number - Electrons = 0 atomic mass number - Protons = 1 atomic mass number - Neutrons = 1 atomic mass number - They are used when a precise measurement is not needed

What are the characteristics of atomic mass units?

- They are very precise measurements of the mass of each atomic particle (electron, proton, neutron) - They are used when a precise measurement is required

What are the characteristics of radioisotopes?

- They have too many neutrons and shed them in an effort to equalize the total number of protons and neutrons. - They are changed into a different atomic species by disintegration of the nucleus accompanied by the emission of ionizing radiation - The are often used in radiation therapy

List the structures of matter from smallest to largest.

1) Atom, 2) Element, 3) Molecules, 4) Chemical compounds

According to the Greeks matter was composed of what four substances?

1) Earth, 2) Air, 3) Water, 4) Fire

The Greeks believed that matter was a combination of the four substances and what four basic essences?

1) Wet, 2) Dry, 3) Hot, 4) Cold

In what year what the Thomson atom disproved and by whom?

1911 by Ernest Rutherford.

What equation determines the maximum number of electrons allowed to be housed in each electron shell?

2n^2

What is the Bohr atom described as?

A "miniature solar system"

What is a chemical compound?

A chemical compound is any quantity of one type of molecule.

What is a molecule?

A molecule is atoms of various elements that may combine to form structures.

What is an isotope?

A naturally occurring atom that has the same number of protons but different numbers of neutrons - They still behave the same way during chemical reactions

What is the chemical symbol for Silver?

Ag

What is the chemical symbol for Aluminum?

Al

Who developed the theory of relativity?

Albert Einstein

What is an atom?

An atom is the building blocks of matter. It is the smallest particle of any matter that has the properties of an element.

What does atomic mass number stand for and where is it found?

Atomic mass number (A) is the number of protons and neutrons in an atom and it is the subscript

What does atomic number stand for and where is it found?

Atomic number (Z) is the number of protons in an atom and it is the superscript

What is the chemical symbol for Gold?

Au

What is the chemical symbol for Barium?

Ba

What is the chemical symbol for Carbon?

C

What is the chemical symbol for Calcium?

Ca

What two forces cause electrons to stay in their orbits?

Centripetal force and centrifugal force

Atoms with lots of protons and electrons have higher _____ and ______.

Centripetal force and electron binding energy

Chemical compounds are created via what type of bonds?

Covalent and ionic bonds

What is the chemical symbol for Copper?

Cu

Describe the Dalton atom.

Dalton suggested elements were made up of identical atoms and were arranged via hooks and eyes. Each element had atoms with various numbers and sizes of hooks and eyes and were very different from one another

Who developed the periodic table and in what year?

Dmitri Mendeleev in 1858

Define radioactivity.

Due to an atom's natural abnormally excited state characterized by an unstable nucleus.

What is the maximum number of electrons allowed to be in the outermost shell of most atoms? Which atom does not follow this?

Eight electrons in most atoms, the only exception is helium (He)

What is the formula for Einstein's mass-energy equivalence equation?

Energy (E) = mass (m) x speed of light in a vacuum (c)^2

What is the chemical symbol for Iron?

Fe

When an atom has eight electrons in its outermost shell it is said to be what?

Filled/very stable

What was new about the Thomson atom?

His atom was the first to mention anything about electric charges, both of the negative electrons and the positive charges.

What is the chemical symbol for Iodine?

I

What does ionic bonding cause? And how?

Ionization, due to the imbalance between positive and negative charges.

Define principle quantum number.

It is a designated number given to each electron shell (K = 1, L = 2, M = 3, ... etc)

Who developed the 1808 version of the atom?

John Dalton

Who was the first to suggest that elements could be classified according to atomic mass values?

John Dalton

All things in the universe have ____ and _____.

Matter, energy

What is the chemical symbol for Molybdenum?

Mo

What are nucleons? Describe each.

Nucleons are the protons and neutrons of the atom. - Protons have a positive charge and weigh slightly less than a neutron - Neutrons are neutrally charged and usually outnumber the total number of protons in a nucleus.

What is the chemical symbol for Lead?

Pb

Describe Rutherford's nuclear model of the atom.

Rutherford said the atom has a small, dense positively charged center called a nucleus and that the nucleus is surrounded by a cloud of electrons.

Describe the theory of relativity.

That matter and energy are interchangeable

Who has the earliest recorded reference to the atom?

The Greeks.

What shell has the highest binding energy? The least?

The K shell always has the highest binding energy. The electron shell furthest from the nucleus always has the least binding energy

What is a chemical symbol?

The abbreviation of the chemical

Define relative binding energy.

The amount of energy needed to keep an electron within its designated orbit.

Describe the Bohr atomic model.

The atom has a small, dense, positively charged nucleus and is surrounded by negatively charged electrons that revolve in fixed well-defined orbits around the nucleus.

What happens during radioactive decay (radioactive disintegration)?

The atoms emit nuclear particles and energy which then transforms them into another atom

How are the seven electron shells within the atom labeled?

The innermost shell is the "K" shell and then it goes K, L, M, N, O, P, Q

Define centrifugal force.

The natural instinct of an electron to travel in a straight line due to its velocity.

Thomson believed ___ and ___ were equal.

The number of electrons and the quantity of positive electrical charge.

In what year did J.J. Thomson develop his atomic model?

The specific year is not know but it is within the 1890's.

What do the groups (columns) stand for in the periodic table? How many are there?

They stand for how many electrons are in the outer shell and there are eight of them.

Describe J.J. Thomson's atomic model.

This model was also called the plum pudding model because Thomson believed that the electrons were like the plums in the pudding, spread out through a mass of positive electrification.

What is the maximum number of electrons allowed to be in the innermost shell of an atom?

Two electrons

What is the chemical symbol for Uranium?

U

What is the chemical symbol for Tungsten?

W

Define ionic bonding.

When two or more atoms are bound together because one atom gave up an outer shell electron.

Define covalent bonding.

When two or more atoms share an outer shell electron