Chemistry midterm Flashcards
0
Q
a variable whose variation does not depend on that of another
A
independent variable
1
Q
a theory or law before it has become well established; a tentative explanation for an observation or a scientific notation that can be tested by further investigation
A
hypothesis
2
Q
a variable whose value depends on that of another
A
dependent variable
3
Q
a variable that is constant and unchanged in an experiment
A
control
4
Q
What is the difference between a theory and a scienfitfic law?
A
a theory is a proposed explanation or observation. it presents a model of the way nature works and predicts behavior that extends well beyond the observations and laws from which it was formed. And on the other hand a scientific law is a statement that summarizes past observations and predicts the future ones. It is usually formulated from a series of related observations.
5
Q
the way that scientists learn about the natural world. It involves observations, laws, hypotheses, theories, and experimentation
A
scientific method
6
Q
SI units: time
A
second
7
Q
SI units: length
A
meter
8
Q
SI units: Mass
A
kilograms
9
Q
SI units: temperature
A
Kelvin
10
Q
SI units: volume
A
Liter
11
Q
Si units: density
A
kilograms
12
Q
is how close a result comes to the true value.
A
accuracy
13
Q
refers to how well experimental data and values agree each other in multiple tests
A
precise
14
Q
what is the density formula?
A
density= mass/volume (d=m/v)
15
Q
a pieve of metal has a density of 13.1 g/mL. If you have a sample with amass of 18,5 g, what is its volume?
A
1.41 mL
16
Q
if you have an object t hat has a mass of 35g and a volume of 7mL, what is density?
A
5 g/mL
17
Q
what is the mass of a piece of wood that has a volume of 6.9 mL and a density of 0.56 g/mL?
A
3.9g
18
Q
the systematic approach used in scientific studies is called \_\_\_\_\_. a hypothesis b control c scientific method d variable
A
c scientific method
19
Q
evolution is an example of a \_\_\_\_\_ a theory b scientific law c control d model
A
a theory
20
Q
the SI unit of mass is the \_\_\_\_\_ a second b meter c kilogram d milliliter
A
kilogram
21
Q
the SI unit of time is the \_\_\_\_ a second b meter c kilogram d none of above
A
a second
22
Q
How many meters are in 540 km? a 540000 m b 5.4 m 54 m d 0.54 m
A
a 540000m
23
Q
how many centimeters are in 35mm? a 3.5 cm b 350 cm c 0.35 cm d 3500 cm
A
a 3.5 cm
24
```
what is the scientific notation for 0.0046?
a 0.46 * 10^4
b 4.6 * 10^3
c 4.6 * 10^-3
d 0.46 * 10^-4
```
c 4.6 * 10^-3
25
```
You are playing darts. All of your darts hit the bulls-eye right in the center. This means you have been
a precise
b accurate
c both precise and accurate
d neither precise not accurate
```
c both precise and accurate
26
```
You are playing darts. All of your darts hit the wall near each other, away from the bulls-eye. This means you have been
a precise
b accurate
c both precise and accurate
d neither precise nor accurate
```
a precise
27
put in scientific notation: 25,000,000
2.5 * 10^7
28
put in scientific notation: 0.00634
6.34 * 1-^-3
29
put in scientific notation: 160
1.60 * 10^2
30
put in scientific notation: 0.0000003
3.0 * 10^7
31
a piece of metal has a volume of 45 mL and a density of 2.0 g/mL. What is its mass?
90 g
32
convert: 470 cm= ____ m
4.7 m
33
convert: 8.046 km = _____m
8046 m
34
convert: 7008 mm = _____ m
7.008 m
35
convert: 175 lbs = ____ kg (1kg= 2.2lbs)
79.5 kg
36
kool-aid
- homogeneous
- heterogeneous
- element
- compound
homogeneous
37
chex mix
- homogeneous
- heterogeneous
- element
- compound
heterogenous
38
oatmenal raisin cookie dough
- homogeneous
- heterogeneous
- element
- compound
heterogeneous
39
brownie mix
- homogeneous
- heterogeneous
- element
- compound
homogenous
40
Calcium oxide (CaO)
- homogeneous
- heterogeneous
- element
- compound
compound
41
silver (Ag)
- homogeneous
- heterogeneous
- element
- compound
element
42
sodium hydroxide (NaOH)
- homogeneous
- heterogeneous
- element
- compound
compound
43
Beryllium (Be)
- homogeneous
- heterogeneous
- element
- compound
element
44
define: can be determined only by changing the substance. Most commonly, include the reactivity of substance
chemical properties
45
define: can be determined without changing a substance. Ex: color density, solubility
physicial properties
46
define: changes that create a new subatance. ex: reaction of sodium and chloine to make sodium chloride
chemical change
47
define: changes that do not create a new substance. for ex: ripping paper, state changes
physical changes
48
```
dissolving salt (NaCl) in water
a chemical change
b chemical property
c physical change
d physical property
```
physicial property
49
```
chopping down a tree
a chemical change
b chemical property
c physical change
d physical property
```
physicial change
50
```
sodium has been found to react violently with water
a chemical change
b chemical property
c physical change
d physical property
```
chemical property
51
```
iron rusting in water
a chemical change
b chemical property
c physical change
d physical property
```
chemical change
52
```
mercury is a silvery liquid
a chemical change
b chemical property
c physical change
d physical property
```
physical proprty
53
```
koolaid powder is soluble in water
a chemical change
b chemical property
c physical change
d physical property
```
physical property
54
```
ice melts on a hot day
a chemical change
b chemical property
c physical change
d physical property
```
physical change
55
```
the density of water is 1.0g/mL
a chemical change
b chemical property
c physical change
d physical property
```
physical property
56
elements on the left side of the periodic table that are often shiny metals that conduct electricity
metals
57
elements on the right side of the periodic table that are either noble gases or soft, brittle solids that do not conduct electricity
non metals
58
elements with properties intermediate of metals and nonmetals and are found along the atair-step line of the meriodic table
metalloids
59
elements that are found in Group 1A. These are very highly reactive metals
alkali metals
60
elements that are found in Group 2A. These are also highly reactive
alkali earth metals
61
elements found in the middle (short columns) of the periodic table
transition metal
62
elements that are found in 7A. they are also very highly reactive
halogens
63
nonreactive elements that are found in group 8A (alll the way to the right of the table)
noble gases
64
vertical columns of periodic table
groups
65
horizontal rows of periodic table
periods
66
chemical formula for: Sodium Carbonate
NA2CO3
67
chemical formula for : C2P4
Carbon Phosphide
68
chemical formula for : Tin (IV) sulfide
Sn2S4
69
chemical formula for : Calcium nitrate
Ca(NO3)2
70
chemical name for : Cs2Se
Cesium Selenide
71
```
Beryllium
atomic mass
atomic number
# of protons
# of neutrons
# of electrons
```
```
9
4
4
5
4
```
72
```
Carbon -12
atomic mass
atomic number
# of protons
# of neutrons
# of electrons
```
```
12
6
6
6
6
```
73
```
carbon -14
atomic mass
atomic numer
# of protons
# of neutrons
# of electros
```
```
14
6
6
8
6
```
74
```
argon
atomic mass
number
# protons
# neutrons
# electrons
```
```
40
18
18
22
18
```
75
```
platium
atomic mass
number
# protons
# neutrons
# electron
```
```
195
78
78
117
78
```
76
```
Which of the following is an example of a homogeneous mixture?
a Sodim (Na)
b sodium chloride (NaCl)
c sugar dissolved in water
d chocolate chip cookie dough
```
c sugar dissolved in water
77
```
which of the following is an example of an element?
a Sodium (Na)
b Sodium chloride (NaCl)
c Sugar dissolved in water
d chocolate chip cookie dough
```
a Sodium (Na)
78
```
On the periodic table, where are the transitions metals located?
a left
b right
c along the stair-step line
d in the middle, in the short columns
```
d in the middle in the short columns
79
```
on the periodic table, where are the noble gases located?
a left-most column (Group 1A)
b right-most column (group 8A)
c along stair-step line
d in middle
```
b right most column
80
```
what is the atomic number of Tungsten (w)?
a 74
b 50
c 88
d 2
```
a 74
81
```
how many protons does an atom of Beryllium have?
a 9
b 5
c 2
d 4
```
d 4
82
```
How many neutrons does an atom of Carbon-12 have?
a 6
b 7
c 8
d 12
```
a 6
83
```
how many electrons does a netral atom of lithium have?
a 3
b 7
c 10
d 2
```
a 3
84
chemical name for LiNO3 (ionic or covalent)
lithium nitrate (ionic)
85
chemical formula : ammonium nitrate (ionic or covalent)
(NH4)3N ionic
86
chemcial name : P2S3 (ionic or covalent)
diphosphorus trisulfide (covalent)
87
mass # formula
mass # = protons + neutrons
88
list at least 2 differences between ionic and covalent bonding.
Ionic bonding is 1 non metal + 1 metal.
Covalent bonding is 1 non metal + 1 non metal.
Ionic bonding is when one atom either loses or gains electron.
Covalent bonding is where they share electrons
89
describe the difference in naming ionic and covalent compounds.
In the ionic bonding you have to add an -ide to the end of the 2nd word
In the covalent bonding you do that as well, but you also have prefixes
90
```
What type of bond is made up of a metal and a nonmetal?
a ionic
b metallic
c molecular
d network covalent
```
a ionic
91
```
What type of bond makes up a very hard solid with atoms connected in all directions?
a ionic
b metallic
molecular covalent
d network covalent
```
a ionic
92
```
What type of bond is in diamond (C(s))?
a ionic
b metallic
c molecular covalent
d network covalent
```
d network covalent
93
What type of bond makes up a substance that is made entirely of nonmetal atoms that does not conduct electricity and is a gas?
a covalent
b ionic
a covalent
94
```
which of the following substances is an example of an ionic bond? (1 non metal and 1 metal)
a NaOH
b NaCl
c MgO
d All of the above
e none of the above
```
d all of the above
95
```
Which of the following substances is an example of a covalent bond (molecular or network)?
a H2O
b CO2
c SiO2
d all of the above
```
all fo the above
96
```
Which of the following elements has 1 valence electron?
a boron
b lithium
c carbon
d phosphorus
```
b lithium
97
```
Which of the following elements has 4 valence electrons?
a hydrogen
b silicon
c neon
d sulfur
```
b silicon
98
```
Which of the following elements is a noble gas and does not bond with other atoms?
a hydrogen
b argon
c oxygen
d florine
```
b argon
99
```
How many valence electrons does iodine have?
a 4
b 5
c 6
d 7
```
d 7
100
```
according to the Octet Rule, how many valence electrons do atoms want to have (with the exception of Hydrogen and Helium)?
a 5
b 8
c 18
d 10
```
b 8
101
synthesis general formula:
A + B = AB
102
decomposition general formula:
AB = A + B
103
single replacement general formula
AB + C = A + BC
104
double replacement general formula
AB + CD = AD + CB
105
Combustion general formula
CH4 + 2O2 = CO2 + 2H2O
106
a form of matter that has definite shape and volume
solid
107
a form of metter that flows, has fixed volume, and an indefinite shape
liquid
108
a form of matter that take the shape and volume of its container; it has no definite shape or volume
gas
109
define: unequal sharing of electrons
polar bond
110
define: equal sharing of electrons
nonpolar bonds
