Brainscape's Knowledge GenomeTM

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


See full index

KME Chemistry > 4 Sem, 2 Exam > Flashcards

4 Sem, 2 Exam Flashcards

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

Four physical properties of metals?

A

a) electrical conductivity
b) thermal conductivity
c) ductility
d) metallic brilliance

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

Electron sea?

A

The freely moving electrons in a metal lattice.

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

Come back.

A

Velocity of an electricity

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

Come back.

A

Velocity/flow rate? of a single electron

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

Electrical conductivity in metals: The electrical conductivity of metals __________ with increasing temperature because the higher the temperature, the stronger the vibration of the metal ________ in the lattice and the more hindered the electrons are from moving freely.

A

decreases, cations

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

Thermal conductivity in metals: In metals, the freely moving valence electrons are not only responsible for the electrical conductivity, they are also necessary for the transport of heat energy. However, the general correlation between electrical and thermal conductance _________________ for other materials. For instance the highly electrically conductive silver is less thermally conductive than diamond, which is an electrical insulator.

A

does not hold, does not work, is not true etc.

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

Ductility in metals: In the metal lattice, there is only one sort of ion (metal _______). When there is a mechanical impact to the metal, the cations are shifted to other positions. But this won’t change the appearance of the metal lattice. Therefore metals are _______ or _______. In contrary, salts are brittle because of the different charged ions in the salt lattice.

A

cations, deformable, malleable

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

Metallic brilliance: This metallic property is also based on the “electron sea”. The extraordinary ________ and ______ of the electrons in the range of visible light account for the shininess of metals.

A

absorbance, reflectivity

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

An alloy is a solid solution of one or more elements in a ___________. Combining one metal with another/more metal(s) or non metal(s) _______ its properties.

A

metallic matrix, enhances

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

The physical properties, such as density, electrical or thermal conductivity of an alloy may not differ greatly from those of its elements, but engineering properties, such as _______ strength and _______ strength may be substantially different from those of the constituent materials. This is sometimes due to the sizes of the atoms in the alloy, since the larger atoms exert a _________ force on neighboring atoms, and smaller atoms exert a ______ force on their neighbors, helping the alloy resist deformation.
Differently sized atoms / molecules interlock well, while same sized atoms do not (ductility).

A

tensile, shear, compressive, tensile

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

Brass composition? (Skip 3)

A

Copper (>52%), zinc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Nickel chromium steel composition? (Skip 3)

A

iron, chromium ( ≈18%), nickel (≈8%), carbon (0.2%)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Amalgam composition? (Skip 3)

A

mercury alloy

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

What is the SI-unit for “amount of substance”?

A

mole (mol)

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

How many particles does 1 mol equal?

A

6.022 * 10^23

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

Mass of one mole of a substance + unit?

A

molar mass (M), g/mol

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

Formula for molar mass?

A 
M = m / n
[g/mol] = [g] / [mol]
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Fancy words for constant temperature, constant pressure and constant volume?

A 
isothermic = const. T
isobaric = const. P
isochoric = const. V
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Law of Boyle-Marionette?

A

P1V1=P2V2,
P*V=constant,
if amount of substance (n) is constant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Law of Gay-Lussac?

A

V1/T1=V2/T2,
V/T=constant,
if amount of substance (n) is constant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Law of Amontons?

A

P1/T1=P2/T2,
P/T=constant,
if amount of substance (n) is constant

22
Q

Combined gas law?

A

P1 * V1 / T1 = P2 * V2 / T2,
P * V / T = constant,
if amount of substance (n) is constant

23
Q

Come back.

A

Draw graphs and pictures of 4 thermal, pressure, volume equations.

24
Q

Ideal gas law?

A

P * V / T = n * R,

R = ideal gas constant = 8.314 J/(mol*K)

25
Q

Standard conditions for Temperature and Pressure (STP)?

A

T = 0°C , P = 1.0 bar / = 1 atm

26
Q

Molar volume of an ideal gas at STP?

A

22.414 l/mol

27
Q

Under the same conditions of temperature and pressure, equal volumes of all gases contain the same number of molecules.

A

Avogadro’s law

28
Q

Composition of air?

A

nitrogen (N2) ≈ 78%
oxygen (O2) ≈ 21%
argon (Ar) ≈ 1%
carbon dioxide (CO2) ≈ 0.04%

29
Q

The reaction rate?

A

how many particles react in a certain amount of time

30
Q

What is the main underlying factor of reaction rate and its two components?

A

the probability of particles colliding,

surface area (in contact between the reacting substances), temperature

31
Q

Reactions where the reacting agents are in different states of matter? Opposite?

A

heterogeneous, homogeneous

32
Q

Factors of reaction rate in homogeneous reactions?

A

temperature,
concentration of the reacting agents (in the solvent),
kind of reaction

33
Q

What is the result of the Landolt reaction/experiment?

A

The reaction rate is directly proportional to the agent concentration.

34
Q

Rule of thumb regarding temperature and reaction rate?

A

An increase of 10°C will double the reaction rate

35
Q

Two different graduated cylinders and two glass tubes with different diameters. At the beginning, the cylinder with the smaller diameter is filled with 50ml of water. The other one s empty. When transferring water with the wider tube from the narrower to the wider cylinder and then transfer water with narrower tube from the wider to the narrower cylinder. The two cylinders will reach a constant level and only change slightly.
This happens when the amount of the transferred liquid in the forward process is equal to the amount of transferred water in the backward process.

A

Water-level equilibrium

36
Q

The reaction rate in an two way reaction is equal in both directions.

A

(State of) chemical equilibrium

37
Q

A + B ≤==≥ C + D
forward (f) —≥
backward (b) ≤—
What are the rate of reactions?

A

Vf = Kf * c(A) * c(B)
Vb = Kb * c(C) * c(D)
Ka/Kb : reaction rate coefficient or rate constant (depends on the temp and reaction kind)

38
Q

A + B ≤==≥ C + D
forward (f) —≥
backward (b) ≤—

A

Vf = Vb
Kf * c(A) * c(B) = Kb * c(C) * c(D)
K = equilibrium constant = Kf/Kb = (c(C) * c(D)) / (c(A) * c(B))
K depends on temp. and reaction kind

39
Q

Show Law of mass action.

A

XA + B + C + etc. ≤==≥ D + YE + F + etc.
K= ___c(D)+c(E)^Y+c(F)+c(etc.)___
. c(A)^X + c(B) + c(C) + c(etc.)

40
Q

Show with constant K equilibrium lies to the right.

A

numerator > denominator
k > 1
k&raquo_space; 1 : Reaction runs almost completely

41
Q

Show with constant K equilibrium lies to the left.

A

numerator

42
Q

What reaction has ∆H>0?

A

Endothermic

43
Q

What reaction has ∆H

A

Exothermic

44
Q

“If a chemical system at equilibrium experiences a disturbance (change in concentration, temperature, etc.), then the equilibrium shifts to compensate the imposed change.”

“Escape from the enforcement!”

A

Principle of Chatelier or Henry Le Chantelier

45
Q

Do the following reactions work better at higher or lower temperatures: exothermic, endothermic?

A

lower, higher

46
Q

Read why: K = f(T).

A

Equilibrium constant depends on the temperature ( K = f(T) ). Different temperatures will cause different K’s. The direction of the shift depends on whether the reaction is ex- or endothermic.

47
Q

In which direction will the equilibrium shift if temperature is raised?

A

To the left if exothermic.

To the right if endothermic.

48
Q

What happens to the equation:
XA + B + C + etc. ≤==≥ D + YE + F + etc.
K= ___c(D)+c(E)^Y+c(F)+c(etc.)___
. c(A)^X + c(B) + c(C) + c(etc.)
when the concentration of one of the reactanting agents or changes?

A

Concentration shifts the equilibrium but the constant K stays the same. In order for this to be true when the concentration of one side changes, so does the other.

49
Q

Which side of the reaction equation does the equilibrium shift when pressure is increased? Or decreased?

A

To the side with less gaseous particles.

To the side with more gaseous particles.

50
Q

In which direction will the equilibrium shift if temperature is lowered?

A

To the left if endothermic.

To the right if exothermic.

KME Chemistry (5 decks)

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