multiple choice 2 Flashcards
CO2(g)+ H2O(g) ⇋ H2CO3(aq) + Heat
According to Le Chatelier’s Principle, what two conditions can be applied to dissolve more
carbon dioxide?
a) Increase pressure and decrease temperature
b) Decrease pressure and increase temperature
c) Increase pressure and increase temperature
d) Decrease pressure and decrease temperature
A - Increase pressure will drive towards right as less gas moles on this side Decrease temp as this reaction is exothermic and this will push towards right hand side
What is the concentration of silver ions in a saturated solution of silver iodide?
a) 4.26 x 10-9 mol L-1
b) 9.23 x 10-9 mol L-1
c) 8.52 x 10-17 mol L-1
d) 9.23 x 10-18 mol L-1
B - AgI Ag+ + I-
Ksp = [Ag+] [I-]
Ksp = 8.52 x 10-17 (from formula sheet) = x2
x = square root of 8.52 x 10-17 = 9.233 x 10-9
Which of the following has the homologous series in order of increasing polarity?
a) Alcohols, alkanes, carboxylic acids
b) Alcohols, carboxylic acids, alkanes
c) Alkanes, alcohols, carboxylic acids
d) Alkanes, carboxylic acids, alcohols
C -
Alkanes = non-polar
Alcohols = polar due to presence of hydroxyl
at end
Carboxylic acids = more polar due to carbonyl
group and hydroxyl group
The table below shows the boiling points of a number of alcohols:
Alcohol Boiling Point (°C)
Methanol 65
Ethanol 78
Propan-1-ol 97
Butan-1-ol 117
What is the cause of the trend observed in the boiling points?
a) Increasing chain length results in stronger dispersion forces
b) Increasing chain length results in stronger hydrogen bonding
c) Hydrogen bonding between hydroxyl groups is stronger in larger molecules
d) Hydrogen bonding between hydroxyl groups is stronger in smaller molecules
A - Only change between molecules is increasing
length of carbon chain = increase dispersion
forces
25.00 mL of 0.02 M potassium hydroxide solution in a conical flask is neutralized by the gradual addition of 33.20 mL of nitric acid.
What is the concentration of the nitric acid?
A. 0.015 mol L-1
B. 0.0265 mol L-1
C. 5 x 10-4 mol L-1
D. 1.66 x 10-5 mol L-1
A
KOH(aq) + HNO3(aq) —- KNO3 (aq) + H2O(l)
n(KOH)= 0.02M x 0.025L = 0.0005 = n(HNO3)
c(HNO3) = n /v = 0.0005 / 0.03320 = 0.015M
What is the concentration of H3O+ in a solution with a pH of 2.38? A. 0.38 mol L-1 B. 11.62 mol L-1 C. 4.17 x 10-3 mol L-1 D. 2.40 x 10-12 mol L-1
C
[H+] = 10-2.38
[H+] = 4.17 x 10-3
Consider the following reaction pathway:
Primary alcohol Oxidation Compound A Oxidation Compound B
Which combination correctly identified Compound A and Compound B?
Compound A Compound B
a) Aldehyde Ketone
b) Ketone Aldehyde
c) Aldehyde Carboxylic Acid
d) Ketone Carboxylic Acid
C - Primary Alcohols oxides first to a aldehyde then to a carboxylic acid
A student analysed the sodium chloride present in a 40.0 g sample of noodle soup. The
chloride ion was precipitated by adding an excess of silver nitrate solution. The silver
chloride was extracted, washed and dried. The mass of silver chloride was 0.752 g.
What percentage of sodium chloride was present in the soup?
A) 0.217%
B) 0.465%
C) 0.767%
D) 1.89%
C
Mass silver chloride = 0.752g
n(AgCl) = m/MM = 0.752g / 143.32gmol-1 =
0.00525mol
n(AgCl) = n(Cl-) = n(NaCl)= 0.00525mol
m(NaCl) = n x MM = 0.00525 x 58.443 =0.307g
%(NaCl) = (0.307/40.0g) x 100 = 0.767%
Native Australian fruits vary from sweet to sour taste. Fruits like Davidson plum and quandong
have a sour or tart taste. This sour taste is attributed to:
a) Sugars like fructose, glucose and sucrose
b) Sugars like fructose, ascorbic acid and sucrose
c) Acids like citric acid, glucose and sucrose
d) Acids like citric acid, tartaric acid and ascorbic acid
D - Acids like citric acid, tartaric acid and
ascorbic acid
Which product would form if water and dilute phosphoric acid where added to pent-1-ene?
a) Pentane
b) Pentan-1-ol
c) 1-Chloropentane
d) Glucose
B - Hydration of an alkene produces an alcohol in
acidic environments.
