ADNOC Schools
T3-Oxidation-Reduction Chemistry
Subject: Pre-AP chemistry
Grade level: 11
Objectives:
-
Predict whether a redox reaction will occur between two reactants using an activity series.
Use stoichiometry principles on oxidation reduction reactions.
Activity Series of metals
Warm up: (Use the words- top, below, above)
1- The most-active element, placed at the ______________ in the series, can replace
each of the elements _____________ it from a compound in a single-replacement
reaction.
2- An element further down can replace any element _______________ it, but not
______________ it.
How to check if a single replacement reaction will occur:
1.
Is the single element reactant higher than the corresponding element in the
reactant compound? Yes, reaction
2.
Is the single element reactant lower than the corresponding element in the
reactant compound? NO reaction (NR)
Use the reactivity series in the figure below to answer the questions that follow:
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ADNOC Schools
T3-Oxidation-Reduction Chemistry
Application 1: (BRONZE)
a) Can iron replace manganese in a single
replacement reaction? ______________ why/
why not
b) Can nickel replace lead in a single
replacement reaction? _____________ Why/why
not?
Application 2: Use the activity series above to
determine if the following reaction will occur. If the reaction occur, write the products
and balance the equation. If the reaction will not occur, write No reaction (NR)
(SILVER)
a) _____ MgCl2 (aq) + ____Zn(s) →
b) Solid nickel is placed in a silver nitrate solution.
c) A silver spoon is placed in a lead (II) nitrate solution.
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ADNOC Schools
T3-Oxidation-Reduction Chemistry
Application 3: Use the activity series below to determine if the following reaction
will occur. If the reaction occurs, write the products and balance the equation. If the
reaction will not occur, write No reaction (NR)
(SILVER)
Look at the activity series to Check whether the metal will or will not react
Metal + acid → Salt + Hydrogen gas
Metal + water → metal hydroxide + Hydrogen gas
Metal +water vapor → metal oxide + hydrogen gas
(107) Reactions Of Metals With Water | Reactions | Chemistry |
FuseSchool - YouTube
1.
Solid aluminum reacts with water vapor.
2.
K(s) + H2O(l) →
3.
Ag(s) + HCl(aq) →
4.
Zn(s) + HCl(aq) →
5.
Mg(s) + H2O(g) →
6.
Cu(s) + HCl(aq) →
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ADNOC Schools
T3-Oxidation-Reduction Chemistry
Problem solving: GOLD+ Challenge:
1. The mass percent of hydrogen peroxide in hair bleaching agent is measured using a titration
based on the equation below. The amount of H2O2 in 14.8 g of hair bleach was determined by
titration with a standard potassium permanganate solution:
MnO4-(aq) + H2O2(aq) + H+(aq)  O2(g) + Mn2+(aq) + H2O(l)
(a) What is the oxidation number of manganese in the permanganate ion, MnO4- (aq)?
(b) Identify the reducing agent in the reaction represented above.
(c) Describe the color change that occurs in
the flask when the end point of the
titration has been reached. Explain why
the color of the solution changes at the
end point.
Color
Hydrogen
peroxide
(H2O2)
colorless
Permanganate
(MnO4-1)
Purple – dark pink
(d) Balance the above redox reaction.
(e) How many moles of MnO4- were required for the titration if 43.2 mL of 0.105 M KMnO4
was needed to reach the end point?
(f) How many moles of H2O2 were present in the 14.8-g sample of bleach?
(g) How many grams of H2O2 were in the sample?
(h) What is the mass percent of H2O2 in the sample?
(i) What effect will adding too much titrant have on the experimentally determined value of the
mass percent of hydrogen peroxide in the bleaching? Justify your answer.
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ADNOC Schools
T3-Oxidation-Reduction Chemistry
Extension work: GOLD+ Challenge
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ADNOC Schools
T3-Oxidation-Reduction Chemistry
Extension work GOLD+ Challenge
The mass percent of iron in a soluble iron (II) compound is measured using a titration based on the
balanced equation below.
A 0.98g sample of the iron (II) compound is carefully measured and then dissolved in distilled water. The
resulting solution is acidified with H2SO4 (aq).
The solution is then titrated with 28.2 mL of 0.025 M MnO4-(aq) until the end point is reached.
(a) Why no indicator is needed in this particular titration?
(b) Describe the color of the solution, explain your answer
At the beginning of titration:
During titration
When the end point of the titration has been reached:
(c) Calculate the moles of MnO4- needed in the titration
(d) Calculate the mass of iron (II) in the sample in grams
(e) Find the mass percent of iron in the iron (II) sample
(f) What effect will adding too much titrant have on the experimentally determined value of the mass
percent of iron in the compound? Justify your answer.
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