Download Study Guide-Chemistry Of Life

Chemistry work sheet
I.
Vocabulary
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
l.
m.
II.
atom
proton
electron
neutron
nucleus (of an
atom)
element
isotope
(radioactive)
compound
molecule
ionic bond
ion
covalent bond
polar covalent
bond
n. nonpolar
covalent bond
o. matter
p. trace elements
q. CHNOPS
r. valence shell
s. valence electron
t. valence number
u. energy level
v. electron shell
w. subatomic
particles
x. atomic number
y. mass number
z. law of
conservation
Matter and Element
1. Which six elements make up 98% of living things?
2. Which of the following is an element?
a. Water (H2O)
b. Carbon dioxide (CO2)
c. Nitrogen (N)
d.
3.
4.
5.
6.
7.
Sugar (C6H12O6)
e. Methane (CH4)
Two important physical properties used to define matter are
_____________ and _______________________
Explain why carbon found in you might have been in a dinosaur a million
years ago?
Does carbon behave the same way in a desk as it does in a living thing?
Explain your answer?
Which of the following is a trace element in the human body?
a. Carbon
b. Hydrogen
c. Oxygen
d. Zinc
Trace elements are:
a. Required by the body in large amounts
b. Required by the body in very small amounts
c. Are not essential for life
d. Are essential for life
e. Both b and d
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III.
Compounds
1. Describe how a compound is different from an element.
2. A substance consists of two or more different elements chemically
combined in a fixed ratio are called a ________________________.
3. Determine if the items listed below are elements or compounds:
a. _____ H2O2, a liquid that no longer resembles either hydrogen
gas or oxygen gas.
b. _____ A substance that can be broken down in a chemical
reaction to other substances.
c. _____ Carbon, the substance represented by the symbol C.
d. _____ Sodium chloride (NaCl) commonly known as table salt.
e. _____ Gold, a substance that cannot be broken down further.
4. Name a compound found in living things that contain the elements carbon,
oxygen, nitrogen, and hydrogen.
5. Give an example of a compound having different properties from its
elements.
IV.
Atomic structure
1. Describe the structure of a nitrogen atom (77N). Use a labeled drawing to
help you explain the structure.
2. A calcium atom has twenty protons and thus has __________ electrons.
3. The nucleus of an atom contains how many protons in an atom with an
atomic # of 5?
4. What gives an element its unique character?
11
5B
5. What is the atomic number of Boron?
6. What is the mass number of Boron?
7. How many neutrons, electrons, and protons does Boron have?
8. Fill in the diagram below.
2
9. Which statement best describes an electron?
a. It has a smaller mass than a proton and a negative charge.
b. It has a smaller mass than a proton and a positive charge.
c. It has a greater mass than a proton and a positive charge.
d. It has a greater mass than a proton and a negative charge.
10. What is the mass # of an atom which contains 28 protons, 28 electrons,
and 34 neutrons?
11. What is the total number of electrons, protons, and neutrons in 5927Co?
12. An element has an atomic number of 18. How many electrons and protons
does it have?
13. An atom has 11 electrons and a mass # of 23. How many neutrons does it
have? What is the atomic number?
14. The mass # is always equal to the total number of its ________________
Plus __________________________
15. A substance composed only of atoms having the same atomic number is
classified as a:
a. compound
b. element
c. mixture
d. solution
CONTINUE ON NEXT PAGE:
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16.
4
17. You are given a bottle of carbon. You are asked to remove a single carbon
at a time until you have one carbon remaining in the bottle. The unit that is
left and that you were removing is what? Carbon is one type of what?
18.
215
45X
a.
b.
c.
d.
e.
What is the atomic number of element X?
What is the mass number of element X?
How many electrons does element X have?
How many protons in element X?
How many neutrons in element X?
19. The negatively charged particle in an atom is called an ______________
20. The positively charged particle in an atom is called a _________________
21. The basic unit of matter is the _____________________
22. The nucleus of an atom contains what subatomic particles?
23. Approximately 99.9% of the mass of an atom is in the what?
24. What is the mass of an atom in AMU’s with 7 protons and 8 neutrons?
25. All atoms of the same substance have the same ______________
26. True or false:
a. ____ Atomic number identifies an atom
b. ____ Each kind of element has a fixed number of protons in its nucleus
V.
Isotopes
Describe the differences and similarities between 126C and 146C
2. Which of the following describes an isotope of the commonly occurring
oxygen atom 168O?
a. 8 electrons, 8 protons, and 9 neutrons
b. 7 electrons, 8 protons, and 8 neutrons
c. 8 electrons, 7 protons, and 8 neutrons
.
d. 7 electrons, 7 protons, and 8 neutrons
1.
E
E
E
N
+
+
+
N
N
3. Look at the atoms above. The atom on the left is a ____________ atom.
The atom in the middle is a ____________ atom. The atom on the right is a
__________________ atom. How can you tell the type of atom?
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4. These atoms above are:
a. ions
b. isotopes
c. have the same mass number
d. from different elements
5. Based on the diagram above, answer the following questions using the
phrase “the same” or “different”
a.
b.
c.
d.
e.
chemical behavior ______________
atomic number ________________
mass number _________________
number of neutrons _________________
number of protons ___________________
6. An isotope of element X below will have how many protons?
215
45X
7. In an isotope of element X, what will change?
8. Describe how radioactive isotopes are beneficial.
9. Describe how radioactive isotopes can be harmful.
10. Describe how radioactive isotopes can be used as biological spies or
tracers.
11. Why do isotopes of the same element have the same chemical properties?
VI.
Electrons and atom behavior
1. A fluorine atom has nine electrons. Make an energy level diagram of
Fluorine. How many electrons would be needed to fill its outer energy
level?
2. A magnesium atom has 12 electrons. When it reacts it usually loses two
electrons. How does this lose make magnesium more stable?
3. The first energy level of an atom can hold how many electrons?
4. The second energy level of an atom can hold how many electrons?
5. To be stable, except for the first energy level, how many electrons are
required in the outermost energy level?
6. In terms of energy, the electrons with the least amount of energy are
located where? The electrons with the most amount of energy are located
where?
7. Differentiate between valence shell and valence electrons.
8. What determines if an atom is stable?
9. What determines if an atom is unreactive?
10. Are the CHNOPS elements stable and unreactive? What are they and
why? Why is this important for living things?
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11. What will unstable and reactive atoms try to do and how?
12. Why is Neon (atomic # 10) unreactive?
13. Complete exercise A below:
EXERCISE A:
CONTINUE ON NEXT PAGE
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13. Complete chart below:
ATOM
Atomic # # of protons # of neutrons # of electrons # of valence electrons Reactive or unreactive
12
C
14
C
14
N
16
O
30
P
32
S
20
10Ne
VII.
Ionic bonds and ions
4th energy
level 1e-
2nd energy
level 8e-
F
atom
K
atom
1st energy
level 2e-
2nd energy
level 7e-
rd
3 energy
level 8e-
1st energy
level 2e-
1. The diagram above shows the arrangement of electrons around the nucleus
of a potassium atom and a fluorine atom. What kind of bond do you think
they would form? Explain your answer.
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2.
3.
4.
5.
6.
Draw a potassium ion and a fluoride ion
What is the charge of the potassium ion? _____________________
What is the charge of the fluoride ion? ______________________
Will the potassium ion attract or repel the fluoride ion?
Does the potassium ion have the same chemical properties as the
potassium atom?
7. In this type of bond between potassium ion and fluoride ion, are electrons
shared or transferred from one atom to another?
8. Describe the difference between a potassium ion and a potassium atom.
VIII.
Covalent bonds
1. How does the formation of an ionic bond differ from a covalent bond?
2. A ____________________ bond involves unequal sharing of electrons
3. An oxygen atom has six electrons in its outermost shell. A hydrogen atom
has one electron in its outermost shell. Describe how the covalent bond in
the water (H2O) molecule enables each atom to achieve stability.
4. What type of bond is characteristic of most of the compounds found in
living things?
5. What is the most common bond formed between CHNOPS elements?
6. Determine the valence number of the following atoms:
14Si
15P
3Li
19K
16S
7. Fill in the chart below:
STATEMENT
IONIC
BOND(S)
COVALENT BOND
(S)
An attractive force between two ions of
opposite charge
Found in the compound NaCl
Increases the stability of atoms
Found in a molecule of water
Results in the formation of a molecule
Is formed when atoms share electrons
Found in most compounds that make up living
things
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8.
a.
b.
c.
d.
Which compound is formed by ionic bonding? Explain.
Which compound is formed by covalent bonding? Explain.
How many electrons are in the third energy level of a magnesium atom?
Which atom forms an ion by the lose of electrons?
10. Which of the following are molecules or compounds or both? Explain why.
a. water (H2O)
b. Salt (NaCl)
c. H2
d. O2
10
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IX.
Chemical reactions:
1.
2.
3.
4.
Distinguish between reactant and product.
Substances that enter into Chemicals reactions are known as ___________
Describe what happens to bonds between atoms during chemical reactions.
Describe the law of conservation
5. C6H12O6 + _____ O2  _____ CO2 + _____ H2O
a.
b.
c.
d.
Balance the chemical equation above.
List the reactants in the chemical reaction above.
List the products in the chemical reaction above.
How many Oxygen molecules are involved in the chemical
reaction?
e. How many oxygen atoms are involved in the chemical reaction?
f. How many carbon dioxide (CO2) molecules are involved in the
chemical reaction?
g. How many total oxygen atoms are in the carbon dioxide (CO2)
molecule(s) found in the chemical equation above?
6. Most chemical reactions within a living organism take place in
______________
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