Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chemistry > Chemistry Exam 1 > Flashcards

Chemistry Exam 1 Flashcards

Chapters 1-5

1
Q

Compounds

A

A substance composed of two or more different chemical elements that are chemically bonded together in a fixed ratio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Mixtures

A

A substance made up of two or more different components that are physically combined but not chemically bonded together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Element

A

A pure substance that cannot be broken down into simpler substances by chemical means

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Pure Substance

A

A material that has a constant composition and distinct properties throughout, with no variation in its chemical make-up

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Homogenous Mixture

A

The components are uniformly distributed with no visible boundaries between them. Examples: air, salt water, vinegar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Heterogenous Mixture

A

The components are not uniformly distributed and have visible boundaries between different phases/components. Examples: sand and water, salt and oil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Changes In State: Which ones require an input of energy?

A

Melting, Boiling, Sublimination (solid to gas)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Changes in State: Which ones release energy?

A

Condensation, Freezing, Deposition (gas to solid)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Chemical vs Physical Changes

A

Chemical changes alter the chemical composition (tarnishing of silver), while physical changes just change in color, boiling point, etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Steps of Scientific Method

A

Step 1: Make Observations
Step 2: Develop a Hypothesis
Step 3: Test the hypothesis through experiments
Step 4: Develop a law (summarize consistent outcomes)
Step 5: Develop a theory (explanation of law)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Scientific Notation

A
  1. Move the decimal point so there is only one non-zero digit to the left of the decimal
  2. Count the number of places the decimal moved
  3. The digit(s) left is the coefficient
  4. The number of places the decimal moved becomes the exponent of 10
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Sig Fig Rules

A
  1. Answer can’t have more sig figs than lowest # sig figs in the calculation
  2. Leading zeros are not significant UNLESS marked by decimal (3500.)
  3. Trailing zeros are signif. (.3000)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Density equation

A

D=M/V

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Specific Heat Capacity

A

Amount of energy needed to raise a certain mass of a substance by 1 degree Celsius

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Exothermic Reactions

A

Release Energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Endothermic Reactions

A

Absorb energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Law of Conservation of Matter (Dalton)

A

When a reaction takes place, matter is neither created nor destroyed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Percent by Mass

A

mass of oxygen in compound divided by total mass of compound times 100

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Dalton’s Atomic Theory

A
  1. All matter is made up of atoms
  2. Atoms can neither be created or destroyed
  3. Atoms of a particular element are alike
  4. Atoms of different elements are different
  5. A chemical reaction involves the union or separation of individual atoms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Rutherford’s Gold Foil Experiment

A
  1. Fired alpha particles at metal foil
  2. Expected a straight flight path for the particles
  3. Some particles flew through and some deflected at a wide angle or “bounced backward”
  4. made him realize there must be something dense inside the atom and negative space
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Rutherford’s Model of the Atom

A
  1. An atom is mostly negative space
  2. A nucleus is a tiny, massively dense, positive-charged unit in the atom (contains protons and neutrons)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Atomic Number

A
  1. # of protons in the nucleus
  2. Determines identity of the atom
  3. An atom with one proton is always a hydrogen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Mass Number

A

Number of protons plus neutrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Isotopes

A

Atoms with the same number of protons but differing numbers of neutrons (exhibit same chemical properties still)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Atomic Mass

A

The actual mass of an atom (given in AMUs or Daltons)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Law of Octaves

A

Elements that are 8 elements apart by mass react in a similar manner (aka chemical periodicity)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Law of Mendelev

A

Properties of elements recur in regular cycles (periodically) when elements are arranged in increasing atomic mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Periods on the Periodic Table

A

-The horizontal rows on the table
-Numbered 1-7 down the table

29
Q

Groups on Periodic Table

A

-The verticle columns on the table
-Also called families
-Either numbered in Roman numerals or Arabic numbers

30
Q

Metals

A

-Shiny solids
-Bendable, malleable
-Conductors of heat and electricity

31
Q

Nonmetals

A

-Brittle
-Do not conduct electricity or heat well

32
Q

Metalloids

A

-Can act as a metal or nonmetal

33
Q

Bohr’s Theory

A

-Electrons are attracted to the nucleus because of their charge
-Energy must be added for the electron to move away from the nucleus
-When the electrons move back to their original positions, energy is released

34
Q

Electrons in Orbits

A

-The closer electrons are to the nucleus, the less energy they possess

35
Q

Valence Shell

A

-Outermost shell of the Bohr model
-The # of electrons in valence shell determines the chemical properties

36
Q

Ground State

A

Lowest energy state (electrons as close to the nucleus as possible)

37
Q

Excited State

A

Any state higher in energy than ground state (1 or more electrons travelled away from nucleus)

38
Q

Subshells & Electron Configurations

A
  • n=1 s2
  • n=2 s2 p6
  • n=3 s2 p6 d10
  • n=4 s2 p6 d10 f14
    *s ALWAYS comes before the next d
39
Q

What Shell Has the Highest Energy?

A

F subshell has highest, lowest is s subshell

40
Q

Electron Configuration Example

A

1s2 2s2 2p6 3p2 3p6 4s2 3d10

41
Q

How to Find Valence Electrons

A

-Do electron configuration (last shell shows valence electrons - but you must add s and d shells together if most outer)
-Find element valency and multiply that and add to any other elements
-count of lewis structure

42
Q

Atomic Size and Periodic Table

A

There’s a decrease in atomic size when you move left to right across a period (increase in atomic size pulls electrons inwards, resulting in decreasing atomic size)

43
Q

Ionization Energy and Periodic Table

A

-Moving from left to right, the ionization energy increases across a period
-Moving down a family, ionization energy decreases

44
Q

Ionization Energy

A

The energy required to remove the outermost electron from an atom

45
Q

Element Size and Periodic Table

A

-Moving across a period, size decreases
-Moving down a group, size increases
*smaller size= more attraction between nucleus and electrons

46
Q

Alkali metals

A

-Group 1A, have low ionization energy and give up electrons easily

47
Q

Halogens

A

-Group 7A, have high ionization energy and would rather gain electrons

48
Q

Alkaline-Earth Metals

A

-Group 2A, have low ionization energy and give up electrons

49
Q

Noble Gases

A

-Group 8A, have a full outer shell and do not form compounds easily

50
Q

Cation

A

-An ion with a positive charge
-Forms when an atom loses one or more electrons, leaving it with less electrons than protons

51
Q

Anion

A

-An ion with a negative charge
-Forms when an atom gains one or more electrons, leaving it with more electrons than protons

52
Q

Do Metals or Nonmetals tend to gain electrons?

A

-Metals tend to lose electrons
-Nonmetals tend to gain electrons

53
Q

Ionic Compounds

A

-Formed by an attraction of ions with opposite charges
-Formed by metals and nonmetals

54
Q

Electrostatic Force

A

The smaller the distance and the larger the charges, the stronger the force holding oppositely charged ions together

55
Q

Molecules

A

-A collection of atoms bound together without forming ions (so they’re electrically neutral
-Have ionic or covalent bonds
-Can’t be broken down physically but can chemically

56
Q

Molecular Compound

A

-Composed of 2 or more types of elements
-Examples: CH4 and H2O

57
Q

Elemental Substance

A

-Composed of only one type of element
-Examples: O2, and Cl2

58
Q

Covalent Bond

A

-Bond that occurs between electrons in one atom and the nucleus of another
-Electrons are usually shared between atoms

59
Q

Ionic Bond

A

-Formed between metals and nonmetals: Metals tend to lose electrons and become cations, while nonmetals gain those electrons to become anions.
-Electrostatic attraction: The opposite charges of the cations and anions attract each other to form the ionic bond

60
Q

Core Electrons

A

Almost never involved in bonding because of their proximity to the nucleus

61
Q

Valence Electrons

A

-Electrons that are shared between neighboring atoms
-Responsible for covalent bonding

62
Q

Energy in Bonds

A

-Bond formation ALWAYS releases energy
-Bond breaking ALWAYS takes energy

63
Q

Diatomic Molecule

A

A molecule composed of only two atoms of the same or different chemical elements (O2, Cl2, H2)

64
Q

Electronegativity (EN)

A

-Measurements for how much an atom wants another electron
-Determines if electrons are transferred or shared when a bond is formed
-Greater the EN, the more likely electrons will be drawn to an atom

65
Q

Pure Covalent Bonding

A

Result when 2 atoms have identical electronegativity

65
Q

Covalency

A

-Non-polar: 0-0.4
-Polar: 0.4-1.7
-Ionic 1.7-4.0
* covalency increases left to right and down to up

65
Q

Polar Covalent Bonding

A

Result when atoms have differing electronegativity (unequal electron sharing)

65
Q

Oxidation

A

-Removal of hydrogen or electrons
-Addition of oxygen

66
Q

Reduction

A

-Addition of hydrogen or electrons
-Removal of oxygen

Chemistry (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions