Chemistry - A Molecular Science

Chapter 1 The Early Experiments

1.12

EXERCISES 1.

Distinguish between a qualitative observation and a quantitative

observation. Give two examples of each.

2. Distinguish among the terms element, compound, atom and molecule. Give

an example of an element that is a mo

lecule and an example of an element

that is an atom.

3. Indicate whether each of the following

represents a mixture of atoms, a

mixture of molecules, or a mixture of atoms and molecules. Is each a mixture of elements, compounds, or

elements and compounds?

(a)

(b)

(c)

(d)

4.

Indicate whether each of the following

represents a mixture of atoms, a

mixture of molecules, or a mixture of atoms and molecules. Is each a mixture of elements, compounds,

or elements and compounds?

(a)

(b)

(c)

(d)

5. Classify each of the following

as an element or compound:

a) P

(^4)
b)^
Fe
c)^
C^3
H^6
O
d) SO
(^2)
e)^
O^3

6. Classify each of the following

as an element or compound:

a)^

H^2

O

b)

C

60

c)^

Au

d)^

CO

e)^

N^2

7. Classify each of the following as an atom or a molecule:

a)

P^4

b)^

Fe

c)^

C^3

H^6

O

d)^

SO

(^2)
e)^
O^3

8. Classify each of the following as an atom or a molecule:

a)

H

O 2

b)^

C^60

c)^

Au

d) CO

e) N

(^2)

9. Classify each of the following as an

atom, molecule, anion, or cation:

a)^

NH

(^3)
b)^
NH
1+ 4
c)
N
3-^
d)^
CH
COO 3
1-^ e)
Si
10.
Classify each of the following as an
atom, molecule, anion, or cation:
a)
Na
1+^
b)^
NO
1-^3
c)^
Na
d)^
Cl
1-^
e)^
Al
3+^
11.
Give the name of each of
the following elements:
a)^
Na
b)^
Br
c)^
Hg
d) Fe
e)^
Ag
12.
Give the name of each of
the following elements:
a)^
Pb
b)^
Au
c)^
F
d) Ca
e)^
P
13.
Write the symbol for each of the following elements:
a)^
copper
b)
lead
c)^
strontium
d)^
silicon
e) tin
14.
Write the symbol for each of the following elements:
a)^
potassium
b)^
iron
c)^
nickel
d)^
cadmium
e)^
selenium
15.
Determine the number of moles of atom
s that are present in each of the
following samples:
a)
5.0 g K
b)
17 g Mg
c)
3.0 g C
d)^
2.2 kg Fe
e)
14 mg Ag
16.
How many moles are in a 5.0-g sample
of each of the following elements?
How many moles of atoms are in each sample?
a)^
Ca
b)
F^2
c)^
O^2
d)
S^8
e) P

. 4

17

. How many moles of molecules are in

a 10.0-g sample of each of the

following compounds? How many moles of atoms are in each sample?

a)^

SF

(^6)
b)^
CCl
(^4)
c) C
H 6
(^14)
d)^
SO
(^3)
e) BF
3
18.
Determine the number of moles of carbon that are present in each of the following samples: a)
1.0 g of aspirin, C
H 9
O 8
4
b)
3.0 g of ibuprofen, C
H 13
O 18
(^2)
c) 12 mg of acetami
nophen (Tylenol), C
H 8
NO 9
(^2)
19.
Determine the mass of the following samples:
a)^
2.5 mol CaCl
2
b)
0.75 mol C
H 6
(^12)
c)^
1.8 mol CO
(^2)
20.
Determine the mass of the following samples:
a)^
4.6
x^10
-3 mol Al(NO
) 33
b)
3.6 mol C
H 12
O 22
(^11)
c) 220 mol H
2
21.
Consider a 5.00 g sample of Ca
S 2

. 3

(^) a)
How many moles of Ca
S 2
does it contain? 3
b)^
How many moles of sulfur does it contain?
c)^
How many grams of sulfur does it contain?
22.
A sample of Al(NO
) 33
contains 0.90 moles of nitrogen.
a)^
How many moles of Al(NO
) 33
are present in the sample?
b)^
What is the mass of the sample in grams?
c)^
How many moles of oxygen are in the sample?
d) How many aluminum atoms are in the sample? e)^
How many grams of aluminum are in the sample?
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North
Carolina
State
University