Aqueous
Redox
Organic
ASB/thermochem
"Surprise"
100
What is the Ks expression for Ag2O
Ks = [Ag+]2[O2-]
100
What is the colour of the Mn2+ ion?
Pale pink, dilute solutions = colourless
100
Describe the tollens test for an aldehyde; reagent and observation
ammoniacal silver nitrate or Ag+/NH3; silver mirror forms
100
define the standard enthalpy of formation
is the enthalpy change when 1 mol of substance is formed from its elements in their standard states
100
What is observed if potassium iodate is added to potassium iodide in the presence of an acid?
Colourless solutions turn brown (due to formation of I2)
200
What is the relationship between s and ks for an AB2 type substance - give both
ks = s3 ks = cube root of ks/4
200
What are the colours of the CrO4 2- and Cr2O7 2-
Yellow & orange
200
How do you use the Lucas test to distinguish between a primary, secondary and tertiary alcohol?
primary - doesnt go cloudy, secondary after 10 minutes, tertiary almost immediately
200
What is the main reason why the chloride ion is bigger than the chlorine atom?
addition of extra electron to same shell causes greater repulsion so they move futher apart
200
Sketch the shape of the titration curve between a WA and SB (as base is added). Will the pH at EP be <7 =7 or >7?
starts around 3, short vertical, pH at EP > 7, finishes around 13-13.5
300
what is the buffer equation?
pH = pka + log [base]/[acid]
300
In an electrochemical cell where does reduction occur; and what is the sign on this electrode?
At the cathode, positive
300
Draw a structure for a condensation polymer between H2N-A-NH2 & HOOC-B-COOH and identify the link formed
H2N-A-NHOC-B-COOH (+ H2O) - AMIDE LINK
300
Draw the lewis diagram for SF4 and predict its shape
See teacher answer (4 bonding pairs, one non bonding pair); distorted tetrahedron
300
Explain why a mixture of CH3COOH and CH3COONa can act as a buffer when small amounts of OH- are added, by an equation
Added OH- reacts with the CH3COOH to make CH3COO- and H2O so pH doesnt change (much)
400
calculate the pH of 0.0150 mol/L CH3COOH given that ka = 1.80 x 10-5
3.28
400
What is the colour of the CuI precipitate? And what are the oxidation numbers of the Cu and the I in this?
White +1 -1
400
How would you convert a tertiary alkyl halide to an alkene; give the reagent and conditions
heat with alcoholic NaOH or KOH
400
What is the general trend in first ionisation energy across a period and why?
increases; increasing effective nuclear charge
400
Draw 2-bromo-3-chlorohexane
CH3CHBrCH2ClCH2CH2CH3
500
What is the pH of 0.500 mol/L CH3COONa if Ka(CH3COOH) = 1.80 x 10-5
9.22
500
Write and combine equations for reaction of bromate (BrO3-) and I- to Br- and I2 under acidic conditions
BrO3- + 6I- + 6H+ ==> Br- + 3I2 + 3H2O
500
Draw the 2 optical isomers of CH3CH(CH3)CHO
eeek..... i cant type this here!!
500
Give the full electron configuration of the Fe2+ ion (atomic number of Fe is 26)
1s2 2s2 2p6 3s2 3p6 3d6
500
List the species in order (most to least) in an aq. solution of NH4Cl excluding water
Cl - > NH4+ > NH3 = H3O+ > OH-
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