Transcript 1st Six Weeks Review

1st Six Weeks Review
Chemistry
1. What are the 4 parts of Dalton’s
Atomic Theory?
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All matter is made up of atoms
Atoms cannot be divided
Atoms combine in whole # ratios (1:2, 2:3,
etc) to form compounds
Compounds react to form new substances
during reactions
2. Describe J.J. Thompson’s
contribution to atomic theory and find a
picture to illustrate it.
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Discovered the Electron
Used Cathode Ray tube experiment
3. Describe Ernest Rutherford’s
contribution to atomic theory and find
a picture to illustrate it.
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Discovered the nucleus
Used the gold foil experiment – shooting
alpha particles at gold foil- some particles
went through, some bounced off in all
directions.
4. Describe Niels Bohr’s contribution to
atomic theory and find a picture to
illustrate it.
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Proposed the planetary model of the atom
Described Electron energy levels
5. Describe Eugene Goldstein’s
contribution to atomic theory find a
picture to illustrate it.
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Discovered the proton
Particles going opposite electrons in cathode
ray tube.
6. Describe James Chadwick’s
contribution to atomic theory find a
picture to illustrate it.
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Discovered Neutrons
7. Describe Erwin Schrodinger
contribution to atomic theory find a
picture to illustrate it.
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Proposed the Quantum Mechanical Model
Orbitals predict location of electrons
Electrons in energy levels
Currently accepted atom model
8. Find a picture & 3 statements that
describe a proton.
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Positive charge
Mass = 1 amu or 1.67 x 10-24g
Found in the nucleus
9. Find a picture & 3 statements
that describe a neutron.
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Neutral charge
Mass = 1 amu or 1.67 x 10-24g
Found in the nucleus
10. Find a picture & 3 statements
that describe an electron.
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Negative charge
Mass = .0005 amu or 1.4 x 10-28g
Moving rapidly around nucleus
11. True or False: The nucleus contains
most of the atom’s volume.
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False!
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The nucleus contains most of the atoms
mass.
The electron cloud contains most of the
atoms volume.
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12. Illustrate an element square from
the periodic table & label the
information it provides.
13. True or False: Most of the volume
of an atom is occupied by the electron
cloud.
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True!
14. A neutral carbon atom has how
many protons, neutrons & electrons?
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Protons = 6
Neutrons = 6
Electrons = 6
Total subatomic particles = ?
15. Magnesium is classified which of
the following: solution, alloy, mixture
or pure substance?
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Pure substance!
16. What is an isotope?
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Isotope is atom of the same element
that has the same # of protons, but a
different # of neutrons
17. What are the three isotopes of
hydrogen? How many protons,
neutrons & electrons does each one
have?
Protons
Protium
1
Deuterium
1
Tritium
1
Neutrons
0
1
2
Electrons
1
1
1
Atomic Mass
1amu
2 amu
3 amu
18. For the isotope Nitrogen-15, how
many subatomic particles are present?
(protons, neutrons, & electrons)
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Total = 21particles
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Atomic # = 7 (7 p, 7e-)
Atomic mass = 14 (14-7 = 7 neutrons)
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19. Potassium has an atomic number
19 and an atomic mass of 39. How
many protons, neutrons and electrons
does it have?
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Protons = 19
Electrons = 19
Neutrons = 39 – 19 = 20
20. What is average atomic mass?
How do you calculate it?
Weighted average of the naturally occuring
isotopes of that element.
To calculate
1. Convert % to decimal
2. Multiply decimal by mass of isotope
3. Add numbers to complete average
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21. What is the
average atomic
mass of silver?
Isotope
Name
Silver-107
Silver-109
Isotope
Percentage
Mass (amu)
106.90509 51.86
108.90470 48.14
.5186 x 106.9amu = 55.438
.4814 x 108.9amu = 52.424
107.9 amu
Extra Practice:
 http://www.algebralab.org/practice/practice.aspx?fil
e=algebra_averageatomicmass.xml
22. Classify each of the following as an
element, compound or mixture:
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Sulfur Salad oil Newspaper Orange MgCl2 Cardboard Apple juice -
Element
Mixture
Mixture
Mixture
Compound
Mixture
Mixture
23. What is density and how do you
calculate it?
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Density is the amount of matter in a given
volume of substance.
m
m
D=V
m = D*V
V=D
24. Visit the following site:
http://www.explorelearning.com/
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Type “Density” in the Search Bar.
Click on “Density Laboratory.”
Click on “Gizmo” above the picture.
Move objects onto the scale & into the
cylinder & calculate the density to predict if
the object will sink or float.
25. Give 4 examples and a picture of
physical changes.
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Cutting
Mixing
Molding
Evaporating
Distillation
Freezing
Condensing
26. Give 4 examples and a picture of
chemical changes.
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Burning
Exploding
Neutralizing
Corroding
Rusting
Draw lines to match the following:
1. Electron
2. Proton
3. Neutron
4. Heterogeneous
5. Homogeneous
6. Mixture
7. Element
8. Compound
9. Pure substance
a. neutral particle w/mass of 1.67 x 10-24 g
b. – particle w/ mass of 9.11 x 10-28 g
c. + particle w/ mass of 1.67 x 10-24 g
d. sample with uniform & definite
composition
e. physical blend of 2 or more substances
f. uniform mixture
g. substance that can be chemically
separated
h. simplest form of a substance
i. mixture that is not uniform throughout