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Flashcards in Stoichiometry Deck (66)
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1
Q

gastric fluid pH

A

~2

2
Q

lysosome pH

A

~3/4

3
Q

bile/pancreas/liver pH

A

basic

4
Q

physiological pH

A

~7.4; veins rich in CO2 (7.2), arteries rich on O2 (7.4)

5
Q

(blank) molecular configuration has (blank) MP and (blank) interaction

A

para; higher; less

6
Q

basicity trend

A

up and left periodic table

7
Q

electronegativity trend

A

up and right periodic table; FONClBrISCH

8
Q

acidity trend

A

down and right periodic table

9
Q

atomic radius/nucleophilicity trend

A

down and left periodic table

10
Q

metals are - acidic/basic?

A

generally, basic

11
Q

Avogadro’s Number

A

6.022x10^23 = 1 mole

12
Q

1 mi = X km

A

1.609 km

13
Q

1 m = X yd

A

1.094 yd

14
Q

1 in = X cm

A

2.54 cm

15
Q

1 kg = X lb

A

2.205 lb

16
Q

1 lb = X g

A

453.6 g

17
Q

1 gal = X L

A

3.79 L

18
Q

1 L = X qt

A

1.06 qt

19
Q

1 hr = X s

A

3600 s

20
Q

convert TF to TC

A

TF= 9/5 (TC) + 32

21
Q

convert TC to TF

A

TC= 5/9 (TF - 32)

22
Q

what temp is the same in *C & *F?

A

-40*

23
Q

density eqn

A

p=m/v

24
Q

what is the same on the moon and earth?

A

mass b/c it isn’t a force but a quantity

25
Q

spec. gravity eqn

A

density(obj) relative to density(h20) (no units)

26
Q

mass % of solute in sol’n=

A

mass(solute)/volume(sol’n) aka density; density of a sol’n changes with temperature.

27
Q

objects float in a medium when…?

A

P(medium)>P(obj)

28
Q

Volume at STP =

A

22.4L/1 mol

29
Q

mass % / % composition by mass=

A

m(atoms)/m(compound) X100%; never >100%; mass% is indpt. of total compound sample mass

30
Q

complete oxidation product of carbon is

A

CO2

31
Q

mass ratio of a compound=

A

(X mol (compound mass))/((Y mol (compound mass))

32
Q

when solving for empirical formula, we assume how much sample mass?

A

100 g

33
Q

what is a molecular formula?

A

the actual mole ratio of elements within a compound; MF= EF x (whole # ratio of MM to the emperical mass/EM); if MM is 2x EM then MF= EFx2

34
Q

what type of analysis is used to determine mass %?

A

combustion analysis

35
Q

molarity (M)=

A

moles solute/volume sol’n (mol/L)

36
Q

molality (m) of a solution=

A

moles solute/ mass solvent (mol/kg); doesn’t change with temperature; used to calculate BP elevation & FP depression of solutions with nonvolatile impurities; 1m= 1 mol solute & 1 kg solvent

37
Q

adding solvent/one solution to a/another solution is known as…

A

dilution; leads to a lower concentration of solute and a higher solution volume and moles of solute remain constant; described in terms of fold (based on total volume) or parts (based on volume added)

38
Q

mass% (in sol’n) =

A

[ ] of a fluid sol’n; (mass solute)/(mass sol’n) x100%; constant with change in temp.

39
Q

dilution eqn

A

M1V1=M2V2

40
Q

mixing 2 solutions means that [solution]f…

A

lies b/w 2 [solution]i values or the average of both [solution]i’s

41
Q

what’s beer’s law?

A

solutes absorb light in a specific wavelength range as EM radiation is passed through a solution; absorbance intensity varies with [solute] (proportional); Abs=eCl, e= solute constant @ wavelength max, C= [solute], l= cuvette length

M=abs therefore, abs1V1=abs2V2

42
Q

reactant A is is the LR when…

A

actual mol reactantA:reactantB>needed mol reactantA;reactantB(of balanced eq’n)

43
Q

what are the 6 inorganic chem rxn types?

A
precipitation rxns (AKA metathesis/double displacement rxns)
acid-base rxns
composition rxns
decomposition rxns
oxidation-reduction rxns
combustion rxns
44
Q

whats a precipitation rxn?

A

2 aq. salts added together form spectator ions and a solid salt precipitate that drops out of sol’n; used to predict products when given only aq. salt reactants.

45
Q

whats an acid-base rxn?

A

an acid/proton donor and a base/proton acceptor form a neutral salt and h20; transfer of an H atom to an -OH of a base

46
Q

what’s a composition rxn?

A

combining of reactants to form a product; #reactants>#products

entropy decreases, bond formation increases compared to bonds broken

opposite of a decomposition rxn; can fall into other categories like redox rxns

47
Q

what’s a decomposition rxn?

A

reactant(s) decompose to multiple products; #reactants<#products

entrop increases, bond formation decreases compared to bonds broken (increases)

opposite of a composition rxn; can fall into other categories of rxns

48
Q

what’s a redox rxn?

A

transfer of electrons from one atom to another;
oxidation = loss of electrons
reduction = gain of electrons; LEO goes GER

oxidation states change in redox rxns

49
Q

in a redox rxn the atom/compound losing electrons is called… and it’s causing…?

A

reducing agent/reductant; reduction

50
Q

in a redox rxn the atom/compound gaining electrons is called… and it’s causing…?

A

oxidizing agent/oxidant; oxidation

51
Q

what’s a combustion rxn?

A

special type of redox rxn where the oxidizing agent is oxygen gas and the products are oxides.

52
Q

combustion rxns of hydrocarbons balance how?

A

CxHy + (x+(y/4)) O2(g) –> xCO2(g) + (y/2)H2O(g)

53
Q

combustion rxns of monosaccharides balance how?

A

CxH(2x)Ox + xO2(g) –> xCO2(g) + xH2O(g)

54
Q

how are oxidation states determined?

A

+1 for every bond formed with a more e-(-) atom
-1 for every bond formed w/ a less e-(-) atom; the sum of these + any formal charges on the atom is the oxidation state for that atom.

O usually -2 except on O2 and peroxides
H usually +1 except in H2 and hydrides
X usually -1 except if it’s a central compound atom in an oxyacid

55
Q

1/6=

A

0.166

56
Q

1/7=

A

0.143

57
Q

1/8=

A

0.125

58
Q

1/9=

A

0.111

59
Q

1/11=

A

0.091

60
Q

1/12=

A

0.083

61
Q

solubility rules for most salts w/ alkali metal cations (Li+, Na+, K+, Cs+, Rb+) & ammonium (NH4+) are…

A

h2o soluble

62
Q

solubility rules for most nitrate (NO3-) salts are…

A

h2o soluble

63
Q

solubility rules for most salts w/ halide anions (Cl-, Br-, I-) are…

A

h2o soluble

exceptions: heavy metals Ag+ & Pb2+

64
Q

solubility rules for most salts w/ sulfate anions (SO4,2-) are…

A

h2o soluble

exceptions: Ba2+, Pb2+, Hg2+, Ca2+

65
Q

solubility rules for most -OH anion salts are…

A

only slightly h2o soluble

KOH & NaOH are substantially soluble but Ca(OH)2, Sr(OH)2, and Ba(OH)2 are fairly h2o soluble

66
Q

solubility rules for most carbonate (CO3, 2-) anion, chromate (CrO4, 2-) anion, phosphate (PO4, 3-) anion, sulfide (S2-) anion salts are…

A

only slightly h2o soluble