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Flashcards in 2EXAM-HChem Deck (83)
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1
Q

___ properties depend on the amount

___ properties depend on type of matter, not the amount

A

Extensive

Intensive

2
Q

Chemical changes (are/are not) reversible

A

Are not

3
Q

Changes of state are (physical/chemical)

What does this include

A

Physical

Boiling, melting

4
Q

Elements are organized in the periodic table by ___ periods and ___ groups

A

7, 18

5
Q

What is evidence of a chemical reaction

A

Production of heat or light, a color change, the production of a gas, or the formation of a precipitate

6
Q

____________ describes that mass is conserved during chemical or physical changes. Mass of reactants=Mass of products

A

Conservation of mass

7
Q

In scientific notation, the base must be…

A

Equal to or greater than 1 and less than 10

8
Q

What is Avogadro’s number

A

6.022 x 10^23

9
Q

What is the difference between accuracy and precision

A

Accuracy: describes how a measurement agrees with the correct or accepted value (bullseye)
Precision: describes how a measurement agrees with other values (consistency)

10
Q

Sig figs contain all of the numbers known for certain plus

A

One estimate

11
Q
What is the SI unit for:
Mass-
Length-
Time-
Amount of substance-
Temperature-
A
Kilogram
Meter
Second
Mole
Kelvin
12
Q

How do you convert C to F

How do you convert F to C

A

F=C*9/5 +32

C=(F-32)*5/9

13
Q

Where are protons and neutrons located

A

The nucleus

14
Q

The number of neutrons =

A

Mass number-number of protons

15
Q

What are the four orbital shapes that electrons can occupy

A

S(sphere), p (peanut), d (double peanut), f (flowers)

16
Q

What is the trend for atomic radius?

What is the trend for ionization energy?

A

Increases left and down

Increases right and up

17
Q

What is ionization energy

A

The amount of energy required to remove the most loosely bound electron, the valence electron, of an isolated gaseous atom to form a cation

18
Q

Electrons want to be unpaired until they’re forced to pair

A

Hund’s Rule

19
Q

When assigning orbitals to electrons, always fill lowest energy first

A

Aufbau’s Principle

20
Q

What are the rules for electron dot notation

A

No side can have more than two dots because each orbital can only hold two electrons
Each side gets one dot before doubling up

21
Q

What is a photon

A

A package of energy that travels on transverse waves

22
Q

The wavelength is between two ___

A

Crests

23
Q

The amplitude of a wave is…

A

The distance from the middle to the top

24
Q

Color of light is established by _____

A

Wavelength

25
Q

_________ is how many waves pass a point in 1 second

A

Frequency

26
Q

Frequency is represented by a __

A

V

27
Q

What are units for frequency

A

Wps, cps, hertz, s^-1

28
Q

_____ travel at the speed of light

A

Electrons

29
Q

electrons start in (lowest/highest) possible energy

A

Lowest (ground state)

30
Q

Increasing wavelength ____ energy

A

Decreases

31
Q

Ionic bonding involves the ____ of electrons

A

Transfer

32
Q

What are the two types of covalent bonding

A

Polar and nonpolar

33
Q

What is electronegativity

A

A measure of the tendency of an atom to attract a bonding pair of electrons

34
Q

How do you calculate N,A,S numbers for atoms/polyatomic ions

A

N is needed (they all need 8 expect H needs 2, Be needs 4, Boron needs 6)
A is available, use valence electron number and look at charge
S is N-A. Divide by 2 and put that number of lone pairs on the central atom

35
Q

What are the two conditions that will result in a molecule being polar

A

One or more lone pairs on center atom (dipoles will angle)

If you have different atoms connected to your center (different electronegativities)

36
Q

_____ are neutral

_____ have a charge

A

Atoms

Ions

37
Q

All elements want to have the electron arrangement of the ______ noble gas

A

Nearest

38
Q

D-block metals form ___

A

Cations

39
Q

Oxyacids contain __,__, and a third element

A

H, O

40
Q

When you’re naming compounds, use the full name of __ and __

A

Sulfur, phosphorus

41
Q

How do you do empirical formula

A

Divide percentage by atomic mass, divide all solutions by smallest number, get whole numbers by multiplying ALL RESULTS

42
Q

How do you find the molecular formula

A

Divide the total mass by the mass present in the compound

Use that as the subscript

43
Q

Empirical formula is _____

Molecular formula is ____

A

Simplest

Actual

44
Q

What are the 5 types of equations

A
Synthesis
Decomposition
Single Displacement
Double displacement 
Combustion
45
Q

Which is NOT a sign that a double replacement reaction will occur
Light is emitted, ppt is produced, H20 is formed, gas is formed

A

Light is emitted

46
Q

The reaction Li+02—>Li20 is …

A

Synthesis and Combustion

47
Q

When you add an acid to a base, the solution ______________

If you add a base to an acid, it ______

A

Stays pink

Flashes pink

48
Q

How do you find the limiting reactant

A

Convert grams of the reactant to grams of the product

Whichever is less is the limiting

49
Q

What must be the units for gas laws

A

Pressure-atm
Volume- l
Temp- K

50
Q

If you’re using the ideal gas law for a wet/dry gas, make sure you have the correct ____ by using Dalton’s law

A

Pressure (subtract or add given water vapor pressure

51
Q

The acid ____ the proton while the base _____ it

A

Donates/accepts

52
Q

The conjugate base goes with the _______

A

Acid

53
Q

What are the rules for naming acids and bases

A
Normal: ic
\+1: per_ic
-1: _ous
-2:hypo_ous
(Look at subscript)
54
Q

When writing rate laws, don’t forget the _

A

K

55
Q

What is the unit for k

A

M^-overall order -1 s^-1

56
Q

The rate determining step is the ___ step

A

Slowest

57
Q

LeChatelier’s Principle says that

A

When you put a stress on a reaction, it will respond to relieve the stress
Also called the equilibrium law

58
Q

Adding a catalyst to a reaction shifts the reaction…

A

NOT AT ALL

NO SHIFT

59
Q

Decreasing the volume makes the reaction shift towards

A

The side with less moles

60
Q

Decreasing volume=

A

Increasing pressure

61
Q

What is entropy

A

Measures the degree of disorder

62
Q

All objects have a tendency to go towards _delta H and _delta S

A

-,+

Less energy, more disorder

63
Q

Endothermic reactions ____ heat and the energy is in the ___

Exothermic reactions _____ heat and the energy is in the ____

A

Absorb, reactant

Release, product

64
Q

What is enthalpy

A

Change in heat (delta H)

65
Q

What is Hess’s Law of Intermediates

A

The heat of formation of the steps must add up to the total

66
Q

What is Hess’s law of summation

A

Heat of reaction=sum of heat of formation of products times moles-sum of heat of formation of reactants times moles

67
Q

Delta Hf values for elements are 0

Why

A

They are naturally occurring and no heat is absorbed

68
Q

In Gibbs, temperature must be in _____

A

Kelvin

69
Q

What element goes in the center for Lewis structure

A

Least electronegative

70
Q

When doing Lewis structure, make sure..

A

Electrons drawn equals A number

71
Q

Mr Cousineau serves ham sandwiches according to the following equation
1Ham+2Bread+1Cheese–>1Sandwich
If Mr. C buys 24 slices of bread, 14 slices of ham, and 16 slices of cheese, which ingredient will be the limiting reactant? (How do you know)

A

The bread
Divide each of the amount of ingredients you buy by the number of ingredients per one sandwich, whichever is the least (bread) is the limiting reactant

72
Q

Nomenclature

Describe the rules for each situation

A

Binary ionic- cation unchanged and then the anion stem+ide
D-block ionic- cation unchanged, Roman numeral, anion stem+ide
Covalent- right of staircase cation, use prefixes di, tri, tetra, penta
Binary acid- hydro_____ic acid
Oxyacid- compare to polyatomic -ate form. Use per___ic, ___ic, ___ous, hypo___ous

73
Q

If you need the mass of one molecule of something, what do you do

A

Convert molecules to moles and moles to grams

74
Q

One mole is different from one _____

A

Molecule

75
Q

How would you find the mass of one molecule of C8H18

A

Convert molecules to moles using Avogrado’s number and then convert moles to grams

76
Q

Is wood heterogenous or homogenous

A

Heterogenous

77
Q

Flammability is a ____ property

A

Chemical

78
Q

Conductor of heat is a ___ property

A

Physical

79
Q

Melting is a ___ property

A

Physical

80
Q

Dissolving readily in water

Physical or chemical

A

Physical

81
Q

Dissolving salt in water is a _____ change

A

Physical

82
Q

Boiling is a ______ property

A

Physical

83
Q

Density is an ___ property

A

Intensive