Download Chemistry 1 Name Atomic theory and structure

Chemistry 1
Atomic theory and structure
Name _________________________
Brainstorm Session!
Before getting started on this worksheet, first brainstorm what you already know about the following topics!
Remember that you are just brainstorming, this involves throwing out ideas and it’s not about being right or
wrong. This is a chance for you to think about what you do know before we dive in!
In your own words and without looking anything up, what are your ideas about….
What is an element? Example?
What is an atom?
Thoughts….did the particle level drawings we drew in Unit 1 represent a single atom or several atoms or
varies based on drawing? Explain.
Ancient Greek Ideas on Particles
We’ve been using circles to represent particles. When did we start thinking matter was made of particles?
Democritus! Quickly skim the 2. Atomist Doctrine and pg212 in your book and then answer the following
questions.
http://plato.stanford.edu/entries/democritus/
Chemistry Book:
1. Who gets credited for suggesting the existence of “atoms”? What time period was this?
2. The word “atom” comes from the Greek word “atomos”, what does this mean?
3. Do you think the word atom is still a accurate term given what you know about the atom thus far?
____________________________________________________________________________________
John Dalton’s Atomic Theory
Slow progress…fast forward 2,000 years later…
4. Who was John Dalton and what was his time in history?
5. In your OWN words, what are the main points of Dalton’s atomic theory? Which part/s of Dalton’s
theory were later found to be in error? Explain why.
6. Using pages 214-215, answer the following questions:
a. How many atoms are in a coin the size of a penny?
b. Giving yourself space, expand this number (take it out of scientific notation). That’s a BIG
number – atoms must be very, very tiny!
c. Can we observe individual atoms with a microscope, if so what kind of microscope? Go back
and take a look at pg. 209 in your book – COOL!.
______________Up to here completed by end of class, continue on if time but not homework!________
Thomson and Rutherford’s Time
7. Draw and label Thomson’s experiment. What was the major discovery from this experiment and what
year?
8. A proposed model of the atom before Rutherford’s experiment was that the atom consisted of electrons
embedded in a material with uniform mass density and charge density.
a) Draw a representation of this model.
b) According to this model, what should happen to the fast, positively-charged alpha particles when
they struck the atom? Show this in your drawing above.
c) What were Rutherford’s actual results from this experiment? What did this suggest about the
structure of the atom and what did the new model look like? Draw a representation.
9. What information about the subatomic makeup of an atom is given by the following?
d) atomic number:
e) mass number:
f) mass number – atomic number:
10. Determine the number of protons, neutrons, and electrons present in each of the following neutral
atoms.
g)
28
14
b)
197
97
c)
40
18
Si
Au
Ar
11. Circle atoms that are isotopes of each other in each of the following sets of atoms.
82
80
h) 80
35 X
35 X
36 X
b)
19
9
X
19
10
X
17
9
X
20
8
X
c)
70
31
X
70
32
X
70
33
X
70
34
X
12. Write the symbol, atomic number and mass # for the atoms with the following characteristics. Assume
all atoms are neutral.
i) Contains 15 neutrons and 13 protons.
j) Contains 33 electrons and 42 neutrons.
k) Iron that contains 84 total subatomic particles.
13. Consider fluorine atoms with 9 protons and 10 neutrons. What are the atomic number and atomic mass
number of this fluorine? Suppose we could add a proton to this fluorine nucleus. Would the result still be
fluorine? Explain. What if we added a neutron to the fluorine nucleus?
14. Write the electron configuration for Platinum.
a. Write the shorthand notation for Platinum
15. Draw an orbital diagram for Aluminum