Download UNIT 1 EXAM REVIEW Scientific Method What are the steps in the

UNIT 1 EXAM REVIEW
Scientific Method
1. What are the steps in the scientific method?
Question
Background Research
Hypothesis
Experiment
Results
Conclusion
Publish
2. I am conducting an experiment to see if the Lions are better with Matt Stafford
at quarter back or not. I watch 10 games of the Lions with Matt Stafford at
quarterback and then I watch the same Lions team for 10 games with a different
quarterback.
a. Come up with a hypothesis for the above experiment.
If Matt Stafford plays QB the Lions will be a better team.
b. What is the independent and dependent variable?
Ind: If Matt plays QB
Dep: Whether or not the Lions will be a better team, this depends on the
independent variable.
c. Based on this season do you think the Lions are a better team with Matt
Stafford at QB?
YES!!!!
3. What are the (SI) units for mass, volume, and distance?
Mass: kilograms (kg), volume: liters (l), distance: meters (m)
Atomic Structure
4. What are the 3 sub-atomic particles that make up an atom?
Protons, neutrons, and electrons
5.
Particle
Mass (in
amu)
Charge
Location in
atom
Proton
1
+
Nucleus
Neutron
1
Neutral
Nucleus
Electron
0
-
Shells outside
nucleus
What happens
if it moves
from atom?
Element
Changes
Becomes
isotope
Becomes ions
6. What force holds the nucleus of an atom together?
Strong nuclear force
7. What is the overall charge of the nucleus?
positive
8. What takes up the most space in an atom?
Nothing, the majority of an atom is empty space!!
9. What is atomic number? What happens if the atomic number changes?
The number of protons in the nucleus of an atom, the element will change if number
of protons is changed.
10. What is atomic mass?
The average number of protons and neutrons inside the nucleus of an atom
11. What is mass number?
Mass number is the specific mass (# of protons and neutrons) for one atom of an
element…usually an isotope
12. What is the difference between atomic mass and mass number? When are mass
numbers used?
Atomic mass is the average mass of all atoms of an element…found on PT
Mass number is a specific mass for one specific atom of an element…used to show an
isotope
13. Using a periodic Table, fill in the following information:
Element Name
Element Symbol
Atomic Mass
Atomic Number
# of protons
# of Neutrons
# of electrons in a
neutral atom
Group #
# of electron shells
Magnesium
Mg
24
12
12
12
12
Arsenic
As
75
33
33
42
33
Nitrogen
N
14
7
7
7
7
Tungsten
W
184
74
74
110
74
Scandium
Sc
45
21
21
24
21
2
3
15
4
15
2
6
6
3
4
14. How can you identify the following? Neutral atom, isotope, ion.
Neutral atoms have the same number of protons and electrons.
Isotopes have a different number of neutrons than protons.
Ions have more or less electrons than protons.
15. What are valence electrons and why are they important?
They are in the outer shell of an atom. They are important because they determine what the
element will bond to. (chemical properties)
16. How many electrons are in the following ions?
a. F -1
10
b. Ca +2
18
c. O-2
10
d. K +1
18
e. Li+1
2
-2
f. S
18
g. N-3
10
17. What is an isotope? How do you write the name of an isotope?
More neutrons than protons in nucleus. Carbon-14, Uranium-238, Nitrogen-15, the number
after element name tells you the mass number (specific mass for that atom)
18. What are the numbers of protons, electrons and neutrons in the following isotopes:
Assume they are neutral…
a. Carbon-13 (6 protons, 6 electrons, 7 neutrons)
b. Uranium- 235 (92 Protons, 92 electrons, 143 neutrons)
c. Nitrogen-15 (7 protons, 7 electrons 8 neutrons)
d. Hydrogen-3 (1 proton, 1 electron, 2 neutrons)
Periodic Table
19. What are the rows on the periodic table called? What do they tell you about the
elements in that row?
Periods, they tell you how many shells an atom of that element has.
20. What are the columns on the periodic table called? What do elements in the
same column have in common?
Groups, they have the same number of valence electrons and similar properties
21. Label the following: Transition metals, metals, non-metals, alkali earth metals,
halogens, alkali metals, noble gases, hydrogen, and oxidation numbers
22. How can you determine the number of valence electrons for each element?
Oxidation #
23. What group of elements are considered stable? How many e- do they have in
their valence shell?
Noble gases, 8 valence electrons
24. What 2 groups are the most reactive? Why is this?
Alkali metals and halogens, they are one valence electron away from becoming stable
25. What are the 2 periodic trends?
Electronegativity and atomic radius
26. What is atomic radius?
The size of an atom
27. What is electronegativity?
How bad an atom wants an electron
28. Draw the correct # of shells and electrons for the following elements. Use your
PT!
Silicon (Si)
Oxygen (O)
Arsenic (As)
29. How can you tell where the metals and non-metals are on the PT?
Metals are to the left of the staircase, non-metals are to the right
30. Are most elements metals or non-metals?
Metals!!
31. What does an oxidation number tell you?
# of valence electrons
Bonding
32. Compare ionic and covalent bonds. Include what electrons do and types of
elements involved.
Ionic are between metals and non-metals and electrons are transferred.
Covalent bonds are between non-metals and non-metals and electrons are shared.
33. What is a cation and anion? What type of bond are they involved in?
Cation is a positive ion
Anion is a negative ion
Involved in ionic bonds…metal becomes cation, non-metal becomes anion
34. Describe how metals and non-metals become ions in ionic bonds.
Metals lose electrons and become positive, non-metals gain electrons and become
negative
35. What are the rules for naming ionic compounds?
Metal goes first, add “ide” to end of the non-metal
Ex. Sodium Chloride
36. What are the rules for naming ionic compounds that involve a transition metal?
If one element is a transition metal you must put a roman numeral indicating number
of valence electrons on 1 atom of transition metal.
37. What are the rules to naming covalent bonds?
Add “ide” to end of second non-metal, must include prefix if more than one atom is in
formula.
38. Name the following P2S3 ? What type of bond is this?
Diphosphorus Trisulfide…covalent bond
39. Name this compound, MgCl2. Is it ionic or covalent?
Magnesium Chloride…ionic
40. What is the name of IrBr3? What is the charge of the cation and anion?
Iridium (III) Bromide
41. What is the formula for Silver (II) Bromide? What is the charge of silver? What is
the charge of bromine?
AgBr2
+2 charge on silver atom
42. What type of bond would Hydrogen and Nitrogen form?
Covalent
43. What is the formula for Gold III Oxide? What is the charge of each ion?
Au2O3
Au+3 and O -2
44. What type of bond would hydrogen and oxygen make?
Covalent
Physical and Chemical Change
45. What is the difference between elements and compounds? Give 2 examples of
each.
Elements are all one type of atom (N2, O2), compounds are 2 or more elements
bonded together (KBr, CO2).
46. What is a molecule? Give 2 examples of a molecule.
Molecule is more than one atom bonded together. H2, H2O, NaCl
47. What is a mixture? Give 2 examples of mixtures.
Two elements or compounds that are not bonded together (NaCl and H 2O) (N2 and O2)
48. Give some examples of physical changes.
Water changing states, a piece of paper being crumpled, butter melting
49. What are some indications that a physical change has occurred?
Object changed shape but no new compound or element was created. Is reversible.
50. What are some examples of chemical changes?
Anything burning, rusting
51. What are some indications a chemical changes has occurred?
A new substance is created. Color changes, odor detected. New molecular
structure, atoms are rearranged, bonds broken
52. C8H13O7
How many atoms of carbon are there in the above molecule? 8
How many atoms of hydrogen? 13
How many atoms of oxygen? 7
How many atoms total? 28