Unit 3 and 4 Flashcards
(144 cards)
1
Q
What did John Dalton do?
A
- Determined atomic masses of elements
- Found how elements combine to form compounds
- Chemical formulas show characteristic proportions
2
Q
The ratio of the two masses of one element that react with a given mass of another element to form two different compounds is the ratio of two small whole numbers
A
Law of multiple proportions
3
Q
Composed of atoms held together in molecules by covalent bonds
A
Molecular compound
4
Q
What are the building blocks of molecular compounds?
A
Molecules containing atoms of 2 Nonmetals
5
Q
A bond between two atoms created by sharing one of more pairs of electrons
A
Covalent bond
6
Q
Nonmetal oxides found in atmosphere
A
CO2, H2O, SO3, SO2, NO
7
Q
A notation showing the number and type of atoms present in one molecule of a molecular compound
A
Molecular formula
8
Q
A compound composed of positively and negatively charged ions held together by electrostatic attraction
A
Ionic compound
9
Q
What two things form an ionic compound?
A
Metallic element and nonmetal
10
Q
A positively charged particle created when an atom of molecule loses one or more electrons
A
Cation
11
Q
A negatively charged particle created when an atom or molecule gains one of more electrons
A
Anion
12
Q
A formula showing the smallest whole number ratio of elements in a compound
A
Empirical formula
13
Q
The smallest electrically neutral unit of an ionic compound
A
Formula unit
14
Q
Group 1 of periodic table
A
Lose 1 electron and form 1+ ions
15
Q
Group 2 of periodic table
A
Lose 2 electrons and form 2+ ions
16
Q
Group 13 of periodic table
A
Lose 3 electrons and form 3+ ions
17
Q
As metallic elements lose electrons in forming ionic compounds, their nonmetallic partners (blank) so overall charge = zero
A
Gain them
18
Q
Group 17 of periodic table
A
1-
19
Q
Group 16 of periodic table
A
2-
20
Q
Group 15 of periodic table
A
3-
21
Q
Steps for molecular formula of a binary molecular compound to form a compound name
A
1) start with name of first element in formula
2) change ending of name of second element to -ide
3) add prefixes to indicate # of atoms
22
Q
Prefix for naming compounds and writing formulas: 1
A
mono
23
Q
Prefix for naming compounds and writing formulas: 2
A
Di
24
Q
Prefix for naming compounds and writing formulas: 3
A
Tri
25
Prefix for naming compounds and writing formulas: 4
Tetra
26
Prefix for naming compounds and writing formulas: 5
Penta
27
Prefix for naming compounds and writing formulas: 6
Hexa
28
Prefix for naming compounds and writing formulas: 7
Hepta
29
Prefix for naming compounds and writing formulas: 8
Octa
30
Prefix for naming compounds and writing formulas: 9
Nona
31
Prefix for naming compounds and writing formulas: 10
Deca
32
Prefix for naming compounds and writing formulas: 11
Undeca
33
Prefix for naming compounds and writing formulas: 12
Dodeca
34
A pure substance composed of two or more elements
Compound
35
Types of compounds
Ionic and molecular
36
Consist of ions
Ionic compounds
37
Consist of molecules
Molecular compounds
38
Smallest unit of a molecular compound that retains the characteristic of that compound
Molecule
39
Indicates the # of atoms of each type within a molecule
Molecular formula
40
Sticks in ball and stick model
Covalent bonds
41
What hold the balls together in a molecule
Covalent bonds
42
A molecular formula that shows structural information and/or groups of atoms
Condensed formula
43
Representation of how atoms are attached within a molecule
Structural formula
44
Charged groups of two or more atoms joined together by covalent bonds
Polyatomic ions
45
Polyatomic ions that contain oxygen in combination with one or more other elements
Oxoanions
46
Compounds that highlight particular chemical properties
Acids
47
What release hydrogen ions when they dissolve in water?
Acids
48
Steps to name binary acids
1) add prefix hydro to name of element and replace last syllable with ic + acid
49
Mass of one molecule of a molecular compound
Molecular mass
50
The mass of one formula unit of an ionic compound
Formula mass
51
Hold together atoms within a molecule
Intramolecular forces
52
Forces between neighboring molecules
Intermolecular forces
53
Used to provide profiles of structures rather than images of single molecules
Atomic force microscopy
54
How do we determine the mass (in grams per mole) of a molecule like ethanol or water?
Molecular weight
55
Sum of atomic weights of all atoms in a molecule
Molecular weight
56
What is another term for molecular weight?
Molar mass
57
Atoms or groups of atoms with a positive or negative charge
Ions
58
Form when atoms lose one or more electrons
Cations
59
Form when an atom gains one or more electrons
Anions
60
What are the general rules for predicting ion charges?
- metals lose electrons to form cations
| - Nonmetals gain electrons to form anions
61
By losing or gaining electrons, atoms have the same # of electrons as the nearest group (blank) atom
8A atom
62
1A ion charge
+1
63
2A ion charge
+2
64
3A ion charge
+3
65
4A ion charge
-4
66
5A ion charge
-3
67
6A ion charge
-2
68
7A ion charge
-1
69
Transition metals charges
Widely variable
70
An ion consisting of more than one atom
Polyatomic ions
71
Steps for naming a binary ionic compound
1) start with name of cation
2) add name of anion (name of element with ending ide)
No prefixes
Electrically neutral
72
Name SrCl2
Strontium chloride
73
Name NaF
Sodium fluoride
74
Name MgO
Magnesium oxide
75
Name CaBr2
Calcium bromide
76
Write the formulae for aluminum oxide
Al2O3
Charges switch when forming subscripts
77
Techniques for the separation of mixtures
Chromatography
78
Formulas of ionic compounds- ionic compounds should have (blank) net charge
No
| Sum of + and - = 0
79
Steps for naming ionic compounds
1) name the positive ion first (cation) followed by the negative ion (anion)
80
What are the negative ions?
```
H-
C4-
N3-
O2-
F-
P3-
S2-
Cl-
Se2-
Br-
Te2-
I-
```
81
Fe2+
| Iron (II) ion
Ferron
82
Fe3+
| Iron (III) ion
Ferric
83
Name CaF2
Calcium fluoride
84
Name Mg(NO3)2
Magnesium nitrate
85
Name Fe3(PO4)2
Iron (II) phosphate
86
KBr
Potassium bromide
87
Li2CO3
Lithium carbonate
88
Coulombs law in words
Cations and anions are attracted to each other by electrostatic forces
89
As ion charge increases, the attractive force (blank)
Increases
90
As the distance between the ions increases, the attractive force (blank)
Decreases
91
Properties of ionic compounds
- exist as 3D arrays of anions and cations
- cations surrounded by anions and vice versa
- tend to be transparent, hard, and brittle as crystalline solids
92
Bonding =
Electron sharing
93
Molecular compounds formed between
2 nonmetals
94
Rules for naming molecular compounds
1) first element in formula is named first, using full element name
2) name the second element as if it were an anion (ide)
3) prefixed are used to denote the number of atoms present
4) prefix mono never used for first element
95
Name NI3
Nitrogen triiodide
96
SF6
Sulfur hexafluroride
97
P4O10
Tetraphosphorus decoxide
98
02F2
Dio y gen difluoride
99
The composition of a compound expressed in terms of the percentage by mass of each element in the compound
Percent composition
100
% composition equation
Mass of element / molar mass x 100
101
Mass in grams of 1 mole of a compound
Molar mass
102
How to find the mass percent of an element:
Mass of element / total mass of the compound
103
Formula determined from percent composition
Empirical formula
104
Steps to find the empirical formula from % composition
1) assume 100 g of substance, % values = mass values, add % to 100
2) convert mass to moles
3) compute mole ratio by reducing one of the mole values to 1
4) convert ratio into whole #s if necessary
105
Represent the relative proportions of the ions in the formula unit of an ionic compound
Empirical formulas
106
The key to translating empirical formulas into molecular formulas is to determine the (blank) and the key to determining this is knowing the (blank)
Value of n
| Molecular mass
107
Who came up with the mass spectrometer?
Francis Aston
108
An instrument that separates and counts ions according to their mass
Mass spectrometer
109
A graph of the data from a mass spectrometer, where m/z ratios of the deflected particles are plotted against the # of particles with a particular mass
Mass spectrum
110
The peak of the highest mass in a mass spectrum; it has the same mass as the molecule from which it came
Molecular ion (M+)
111
Simplest whole number ratio of elements in a compound
Empirical formula
112
How do you determine the molecular formula?
Obtain the molar mass of the compound experimentally (mass spectrometer)
113
What are the 3 steps to get a molecular formula?
1) get exp data
2) determine the mass of the empirical formula
3) find the ratio of the mass
114
Ionic compounds having water molecules trapped in their lattice
Hydrated compounds
115
Compounds without water (may be obtained by heating)
Anhydrous compounds
116
The quantitive relation between reactants and products in a chemical reaction
Stoichiometry
117
The sum of the masses of the reactants in a chemical reaction is equal to the sum of the masses of the products
Law of conservation of mass
118
A class of organic compounds composed of only hydrogen and carbon
Hydrocarbons
119
A heat-producing reaction between oxygen and another element or compound
Combustion reaction
120
What are the only products when the combustion of a hydrocarbon is complete?
Carbon dioxide and water
121
What are key reactions in the carbon cycle?
Photosynthesis and respiration
122
What two things do we need to know to determine mass of any substance involved in any chemical reaction?
1) mass of another substance in reaction
| 2) stoichiometric relation between 2 substances
123
Chemical equations indicate
The kind of reactants and produces
| Relative amounts of reactants and products
124
The relationship between the amount of chemical reactants and products
Stoichiometry
125
The numbers in front of reactants and products
Stoichiometric coefficients
126
S, g, l, aq represent
Physical states of reactants and products
127
Matter can neither be created nor destroyed
Law of conservation of matter
128
The burning of organic compounds (fuel) in oxygen with the evolution of heat, CO2, and H2O
Combustion reaction
129
Steps to balance combustion reactions
1) write out correct formulas for reactants and products
2) balance C atoms
3) balance H atoms
4) balance O atoms
5) check work
130
The study of the quantitative aspects of chemical reactions
Stoichiometry
131
Stoichiometry problems should be attempted only when you have a (blank) chemical equation
Balanced
132
Maximum quantity of product that can be produced in a reaction
Theoretical yield
133
General plan for stoichiometry calculations
Mass reactant- moles reactant- stoichiometric factor- moles product- mass product
134
Percent yield
(Actual yield / theoretical yield)x100
135
A reactant that is consumed completely in a chemical reaction
Limiting reactant
136
The maximum amount of product possible in a chemical reaction for given quantities of reactants
Theoretical yield
137
The amount of product obtained from a chemical reaction, which is often less than the theoretical yield
Actual yield
138
The ration, expressed as a %, of the actual yield of a chemical reaction to the theoretical yield
Percent yield
139
The reagent in short supply (blank) the quantity of product that can be formed
Limits
140
Limiting reagent =
Limiting reactant
141
What are the two types of limiting reagent problems?
1) 1:1 ratio of reactants
| 2) non 1:1 ratios of reactants
142
Limiting reagent dictates (blank)
Theoretical yield
143
A laboratory procedure for determining the composition of a substance by burning it completely in oxygen to produce known compounds whose masses are used to determine the composition of the original material
Combustion analysis
144
Combustion analysis yield the percentages by mass of all atoms in a sample except (blank)
Oxygen
