QUIZ 1!

Question 1

What did Thales think was the universal element? What did he contribute?

Answer 1

water

argued that Earth floated on water

Question 2

What did Anaximander think was the universal element? What did he contribute?

Answer 2

earth
focused on opposites found in nature
argued for “Apeiron”

Question 3

What did Anaximenes think was the universal element?

Answer 3

air

used observations of rarefaction and condensation to conclude that air is the primary substance

Question 4

What did Heraclitus think was the universal element?

Answer 4

fire
believed in constant change and transformation
death of fire is birth of everything else

Question 5

What is meant by the term “atomism” as a philosophy?

Answer 5

nature consists of “atom” and “void”

Question 6

What did Empedocles contribute?

Answer 6

material pluralism

air, earth, water, fire

Question 7

What contributions did Democritus and Leucippus make to atomism?

Answer 7

originated atomism, thought stuff was formed when atoms fall into the void and are tangled with each other

Question 8

What were five postulates of Leucippus and Democritus’ atomism?

Answer 8

all matter is made of atoms
the volume in between atoms is empty space
atoms are always in constant motion
there are infinite numbers of atoms
atoms vary in shape and size

Question 9

Why was the atomism of Leucippus and Democritus relatively obscure until the early 1800’s?

Answer 9

it wasn’t agreed upon by influential philosophers, but by 1800s there was enough empirical evidence

Question 10

Why were Greek philosophers so interested in material monism rather than pluralism?

Answer 10

sorting the world into elements was simpler and easier to understand

Question 11

Who was Aristotle and what did he contribute?

Answer 11

proposed existence of 5th element (aether) found in celestial regions and heavenly bodies

Question 12

What contributions did Leucippus make to the development of the atomic model?

Answer 12

theorized the principle of the atom as a fundamental basis of nature

Question 13

What contributions did Democritus make to the development of the atomic model?

Answer 13

spread the atomist view of nature into the academic community

Question 14

What contributions did Antoine Lavoisier make to the development of the atomic model?

Answer 14

• Law of Conservation of Mass
• mass is neither created nor destroyed
  wrote first extensive list of elements

Question 15

What contributions did Joseph Louis Proust make to the development of the atomic model?

Answer 15

Law of Definite Proportions

- in a pure compound, elements are always present in the same proportion by mass

Question 16

What contributions did John Dalton make to the development of the atomic model?

Answer 16

Law of Multiple Proportions

- ratio of mass of one element that combines a fixed mass of a second element to make 2 different compounds

Question 17

What did John Joseph Thomson contribute to the development of the atomic model?

Answer 17

realized that atoms have a positive and negative component

Question 18

What did Ernest Rutherford contribute to the development of the atomic model?

Answer 18

determined that the positive charge of an atom is concentrated into a small nucleus and negatively charged electrons are in a larger volume of space around the nucleus

Question 19

What did Neils Bohr contribute to the development of the atomic model?

Answer 19

he created a model that placed electrons in orbits around the nucleus

Question 20

What did Louis de Brogile contribute to the development of the atomic model?

Answer 20

proposed that all matter has wave properties, especially electrons
showed that electrons don’t orbit the atom

Question 21

What did Erwin Schrodinger contribute to the development of the atomic model?

Answer 21

proposed a new model with the electron in a region of space called orbital

Question 22

What are the 5 postulates of John Dalton’s atomic theory?

Answer 22

all elements are made of atoms
atoms of a given element are identical
atoms can’t be created, destroyed, or subdivided
atoms combine in simple whole number ratios to form chemical compounds
atoms combine, separate, and rearrange in chemical reactions

Question 23

How are the atomic theories of Leucippus/ Democritus and John Dalton alike?

Answer 23

everything is made of atoms
atoms in different elements are different
they vary by shape and size

Question 24

Why was John Dalton’s atomic theory more quickly accepted by his contemporaries than was the atomic theory of Leucippus and Democritus?

Answer 24

supported his ideas with empirical evidence developed by himself and others

Question 25

What is the meaning of the term “Subatomic particle”?

Answer 25

A subatomic particle is a particle that is smaller than an atom and is usually a constituent particle of
most atoms.

Question 26

Who is the first person credited with first characterizing the electron?

Answer 26

J.J. Thomson

Question 27

What are the properties of an electron?

Answer 27

subatomic particles with a negative charge.
mass of 9.109 x 10-28 grams.
not located in the nucleus of an atom but are instead located in the electron cloud.

Question 28

Who is the first person credited with characterizing the proton?

Answer 28

Ernest Rutherford

Question 29

What are the properties of a proton?

Answer 29

subatomic particles having a positive charge.
mass of 1.673 x 10-24 grams.
located in the nucleus of an atom.
nucleons because they are located in the nucleus of an atom.

Question 30

Who is the first person credited with characterizing the neutron?

Answer 30

James Chadwick

Question 31

What are the properties of a neutron?

Answer 31

subatomic particles that do not have an electrical charge.
mass of 1.675 x 10-24 grams.
located in the nucleus of an atom.
nucleons because they are located in the nucleus of an atom.

Question 32

Who is the first person credited with characterizing the nucleus of an atom?

Answer 32

Ernest Rutherford

Question 33

What are the properties of the nucleus of an atom?

Answer 33

contains all of an atom’s protons and neutrons.
very small and dense when compared to the rest of the atom.
always positively charged.
contains almost all of an atom’s mass.

Question 34

Why does the nucleus of every atom have an overall positive charge?

Answer 34

The nucleus of an atom is always positively charged because of the positively charged protons
within it. The other particles located in the nucleus – the neutrons – do not have an electrical charge
and therefore do not affect the overall charge of the nucleus.

Question 35

Why is almost all the mass of an atom located in its nucleus?

Answer 35

The nucleus of an atom contains almost all of the atoms mass because the two particles found
within it – the protons and the neutrons – are each 1837 times and 1839 times, respectively, more
massive than the electrons in the electron cloud of the atom.

Question 36

What is the meaning of the term “nucleon”?

Answer 36

any subatomic particle found in the nucleus of an atom. Since all atomic nucleuses,
other than the simplest form of hydrogen, contain protons and neutrons, those particles; that is
protons and neutrons, are considered to be nucleons.

Question 37

What are the properties of the “electron cloud” in an atom?

Answer 37

a relatively large region of the atom when compared to the nucleus.
mostly empty space in which the electrons move about.
the electrons – are negatively charged, the
electron cloud itself is considered to be negatively charged.

Question 38

Why is an atom always electrically neutral?

Answer 38

for every proton located in its nucleus,
there is a corresponding electron located in its electron cloud.
Since the neutrons do not have an electrical charge, they have no effect on the overall charge of
the atom.