Gas Stoich: PV = nRT P = pressure (kPa) V = volume (L) n = number

Year 11 Chemistry (ABE)
End of Year Examination Revision
-----------------------------------------------------------------------------------------------------------------------------------------------------------------
Gas Stoich:
!
PV = nRT
!
!
P = pressure (kPa)! !
!
!
!
n = number of moles (mol)!!
!
!
T = temperature (K)
!
101.3 kPa = 1 atm = 760 mmHg! !
!
!
!
!
V = volume (L)
R = general gas constant - 8.31
!
!
oC
+ 273 = K
Redox:
!
Reduction is a decrease in oxidation number, and is gaining electrons
!
Oxidation is an increase in oxidation number, and is losing electrons
!
Order for balancing half-equations:
1) Balance all exc. O, H
2) Balance O by adding H2O
3) Balance H by adding H+
4) Balance charge by adding e!
Adding half-equations together - multiply half-equations until the electrons on each side cancel
!
The oxidant causes oxidation, and undergoes reduction
!
The reductant causes reduction, and undergoes oxidation
Galvanic Cells:
!
You need to be able to look at the electrochemical series and predict whether a reaction will
!
occur, and the half reactions and overall equation likely to occur
!
!
Top left / bottom right OR clockwise
!
Drawing a galvanic cell:
• Label each half-cell with the ion in solution and the electrode (if there are the two
species in solution, or youʼve got a gas and an aqueous, the electrode is C or Pt)
• Label the electron flow through the external circuit
• Show the direction in which ions flow through the salt bridge
• Label the anode and cathode
• Label the positive and negative electrode
Stoich:
!
n=m/M
!
!
n = amount in moles (mol)!!
!
!
!
M = relative molecular mass (g mol-1)
!
n=c*V
!
!
n = amount in moles (mol)!!
!
!
!
V = volume (L)
Acids and Bases:
!
pH = -log[H3O+]
!
[H3O+] = 10-pH
!
[H3O+] [OH-] = 10-14 M2
!
!
In pure water at 25oC
!
m = mass (grams)
!
c = concentration (M)
Year 11 Chemistry (ABE)
End of Year Examination Revision
-----------------------------------------------------------------------------------------------------------------------------------------------------------------
Redox:
1) Balance the following half-equations, and label the oxidation numbers in each species present:
a) Fe(s) → Fe+3(aq)
b) Al2O3 (l) → Al(l)
c) Fe2O3 (l) → Fe(l)
d) Fe3O4 (l) → Fe(l)
For each redox reaction, determine:
a) the oxidation half-reaction,
b) the reduction half-reaction,
c) the oxidant,
d) the reductant and
e) the balanced redox reaction
2) Fe3+ + Sn2+ → Fe2+ + Sn4+
3) Fe2+ +ClO3− + H+ → Fe3+ +Cl− + H2O
4) CuNO3 + H+ → Cu2+ + NO + H2O
5) S2O42− + Ag2O + H2O → SO32− + Ag + H+
6) MnO4− + Cl− + H+ → Mn2+ +Cl2 + H2O
Galvanic Cells:
Use the Electrochemical Series attached.
For the following pairs of half-cells, predict whether a reaction will happen. If no reaction will occur,
write ʻNO REACTIONʼ. If a reaction will spontaneously occur, draw the galvanic cell including:
a) Identifying the two species in each half-cell
b) Writing the half-equations for each half-cell
c) Writing the overall equation
d) Label the electron flow through the external circuit
e) Define an appropriate salt for the salt bridge
f) Show the direction in which ions flow through the salt bridge
g) Label the anode and cathode
h) Label the positive and negative electrode
1) F2/F- and Zn/Zn2+
2) Co2+/Co and Pb/Pb2+
3) Cu2+/Cu and I2/I4) Sn4+/Sn2+ and Sn2+/Sn
5) Fe3+/Fe2+ and Cu/Cu2+
Year 11 Chemistry (ABE)
End of Year Examination Revision
-----------------------------------------------------------------------------------------------------------------------------------------------------------------
Stoich:
1) Na2SIO3(s) + 8HF(aq) → H2SiF6(aq) + 2NaF(aq) + 3H2O(l)
a) How many moles of HF are needed to react with 0.300 mol of Na2SiO3?
b) How many grams of NaF form when 0.500 mol of HF reacts with excess Na2SiO3?
c) How many grams of Na2SiO3 can react with 0.800 g of HF?
2) C6H12O6(aq) → 2C2H5OH(aq) + 2CO2(g)
a) How many moles of CO2 are produced when 0.400 mol of C6H12O6 reacts in this fashion?
b) How many grams of C6H12O6 are needed to form 7.50g of C2H5OH?
c) How many grams of CO2 form when 7.50 g of C2H5OH are produced?
3) Fe2O3 (s) + CO(g) → Fe(s) + CO2(g) (unbalanced!)
a) Calculate the number of grams of CO that can react with 0.150 kg of Fe2O3
b) Calculate the number of grams of Fe and the number of grams of CO2 formed when 0.150 kg of
Fe2O3 reacts
4) 2NaOH(s) + CO2(g)→ Na2CO3(s) + H2O(l)
a) Which reagent is the limiting reactant when 1.85 mol NaOH and 1.00 mol CO2 are allowed to
react?
b) How many moles of Na2CO3 can be produced from the above reaction?
Acids and Bases:
1) Complete the following table:
[H3O+]
1.0 x 10-9 M
[OH-]
pH
Acidic/Basic?
4.1x10-2 M
3.75
2.82 x
10-9
M
2) What is the pH of a solution that contains 25 grams of hydrochloric acid (HCl) dissolved in 1.5 liters
of water?
3) What is the pH of a solution that contains 1.32 grams of nitric acid (HNO3) dissolved in 750 mL of
water?
4) What is the pH of a solution that contains 1.2 moles of nitric acid (HNO3) and 1.7 moles of
hydrochloric acid (HCl) dissolved in 1000 liters of water?
5) If a solution has a [H+] concentration of 4.5 x 10-7 M, is this an acidic or basic solution? Explain.
6) An acidic solution has a pH of 4. If I dilute 10 mL of this solution to a final volume of 1000 mL,
what is the pH of the resulting solution?