A: Chemistry = Chemical Changes 2.2 The Gain and Loss of Electrons Flashcards
What percentage of copper can be found in ore today?
Less than 2%
This refers to the copper extracted from rock in modern mining operations.
What is the first product obtained from the first set of furnaces during copper extraction?
Copper(I) sulfide
This is the initial form of copper after processing rock.
Cu2S
What is blister copper?
97% to 99% pure copper
The name comes from the appearance of its surface due to escaping sulfur dioxide gas.
What happens to copper(I) sulfide when air is blown over it?
Sulfur is removed
This treatment converts copper(I) sulfide into blister copper.
Fill in the blank: Ore is a rock that contains a useful metal in a _______ concentration that makes it economical to mine.
sufficient
What is the process required to separate copper from unwanted minerals?
Mining, crushing, and heating in furnaces
This process is essential for copper extraction from ore.
True or False: Blister copper is created during the cooling process of molten copper(I) sulfide.
True
The blistering occurs due to the release of sulfur dioxide gas.
What contaminants are often found in copper ore?
Iron and other minerals
These contaminants necessitate extensive processing to extract copper.
What is blister copper?
Blister copper is 97% to 99% pure copper that appears blistered due to escaping sulfur dioxide gas while solidifying.
Blister copper is an intermediate product in the extraction of copper from its ores.
What is the purity range of blister copper?
97% to 99% pure.
This high level of purity makes blister copper suitable for further refining.
What happens during the production of blister copper?
Air is blown over molten copper sulfide.
This process aids in the oxidation of the copper sulfide.
Write Reaction 1 that occurs in the production of blister copper.
2 Cu₂S(s) + 3 O₂(g) → 2 Cu₂O(l) + 2 SO₂(g)
This reaction illustrates the transformation of copper sulfide to copper oxide and sulfur dioxide.
Write Reaction 2 that occurs in the production of blister copper.
2 Cu₂O(d) + Cu₂S(s) → 6 Cu(l) + SO₂(g)
This reaction shows the reduction of copper oxide to produce molten copper.
What is blister copper?
Blister copper is 97% to 99% pure copper that appears blistered due to escaping sulfur dioxide gas while solidifying.
Blister copper is an intermediate product in the extraction of copper from its ores.
What is the purity range of blister copper?
97% to 99% pure.
This high level of purity makes blister copper suitable for further refining.
What happens during the production of blister copper?
Air is blown over molten copper sulfide.
This process aids in the oxidation of the copper sulfide.
Write Reaction 1 that occurs in the production of blister copper.
2 Cu₂S(s) + 3 O₂(g) → 2 Cu₂O(l) + 2 SO₂(g)
This reaction illustrates the transformation of copper sulfide to copper oxide and sulfur dioxide.
Write Reaction 2 that occurs in the production of blister copper.
2 Cu₂O(d) + Cu₂S(s) → 6 Cu(l) + SO₂(g)
This reaction shows the reduction of copper oxide to produce molten copper.
Where are most metals typically found?
In rock formations as ores
What are the metal atoms in an ore commonly bonded to?
Non-metal atoms, often oxygen or sulfur
What charge do metal ions in compounds have?
Positive charges
Fill in the blank: Metal ions in compounds have _______ electrons.
lost
True or False: Most metals are found in a pure form in nature.
False
What type of compounds do metal atoms in ores typically form?
Ionic compounds
Why are metals usually found locked up in ionic compounds in ore deposits?
Metals are more stable when their outer energy levels resemble those of noble gases, which is achieved by combining with non-metals.
What is the most stable arrangement for metals?
To have their outer energy levels resemble those of noble gases.
What happens during the combination of silver and sulfur atoms?
There is a transfer of electrons from the metal (silver) to the non-metal (sulfur).
What are some conditions under which silver can combine with sulfur?
Extreme conditions like inside a volcano or ordinary conditions like a silver spoon on a kitchen counter.
How is a metal structured in terms of charge and electrons?
A metal is made up of positively charged particles within a ‘sea’ of free-floating electrons.
Fill in the blank: The process of a metal combining with a non-metal involves a transfer of _______.
[electrons]
True or False: Pure metal outcrops are common.
False
What is the chemical symbol for silver?
Ag
What happens to free-floating electrons in metal atoms?
They can be lost to other atoms, turning the metal atoms into positively charged ions.
What is the result of losing electrons from metal atoms?
Formation of positively charged ions.
What is the reaction that describes the loss of an electron from silver?
2x Ag(s) → Ag’ (ag) + 1e
What attracts positive metal ions in ionic crystal formation?
Negative ions that have received the electron.
What forms the crystal structure that appears as black tarnish on silver?
An ionic compound formed by the attraction of positive and negative ions.
Fill in the blank: The process of forming an ionic crystal involves the attraction of _______ ions to _______ ions.
positive, negative
True or False: Silver tarnish is a result of the formation of ionic compounds.
True
What is the visual appearance of tarnish on silver surfaces?
Black tarnish
What is oxidation?
A chemical process involving the loss of electrons.
Fill in the blank: Oxidation involves the loss of _______.
electrons
True or False: Oxidation can only occur in isolated systems.
False
What is the significance of oxidation in chemical reactions?
Oxidation is crucial for energy production and metabolic processes.
List two examples of oxidation processes.
- Combustion
- Respiration
Fill in the blank: Oxidation often occurs simultaneously with _______.
reduction
Define reduction in the context of oxidation-reduction reactions.
A chemical process involving the gain of electrons.
What is the relationship between oxidation and reduction?
They are complementary processes; oxidation involves electron loss, while reduction involves electron gain.
What happens to neutral atoms during oxidation reactions?
Neutral atoms lose electrons and become positively charged ions.
This is a fundamental concept in oxidation-reduction (redox) reactions.
In oxidation reactions, what do negatively charged ions do?
Negatively charged ions lose electrons to become neutral atoms.
This process is part of the electron transfer in redox reactions.
What occurs when positively charged ions undergo oxidation?
Positively charged ions lose electrons to become even more positively charged.
This is significant in understanding how oxidation states change.
Fill in the blank: Neutral atoms lose _______ and become positively charged ions.
electrons
Fill in the blank: Negatively charged ions lose electrons to become _______.
neutral atoms
True or False: Positively charged ions gain electrons during oxidation.
False
What is the essential task in processing ore to produce copper?
To reverse the oxidation reaction that has locked the copper metal into compounds like copper sulfide.
How much pure copper can be produced from 1000 kg of ore?
Less than 20 kg.
What is the typical yield of pure silver from 1000 kg of ore?
About 0.1 kg.
What is the process of giving back electrons to metal ions called?
Reduction.
What happens to metallic ions during the refining process?
They are given back the electrons they lost.
What is the outcome of the reduction process in purifying metals?
The metal is no longer part of the ionic compound.
What occurs when atoms gain electrons?
They undergo a process called reduction.
True or False: Reduction involves a loss of electrons.
False.
Fill in the blank: Reduction is a chemical process involving a _______.
gain of electrons.
From where does the term ‘reduction’ originate?
The metal-refining industry.
Why is the term reduction expanded to include any reaction with electron gain?
Historically, it refers to reducing large amounts of ore to smaller amounts of pure metal.
What is the essential task in processing ore to produce copper?
To reverse the oxidation reaction that has locked the copper metal into compounds like copper sulfide.
How much pure copper can be produced from 1000 kg of ore?
Less than 20 kg.
What is the typical yield of pure silver from 1000 kg of ore?
About 0.1 kg.
What is the process of giving back electrons to metal ions called?
Reduction.
What happens to metallic ions during the refining process?
They are given back the electrons they lost.
What is the outcome of the reduction process in purifying metals?
The metal is no longer part of the ionic compound.
What occurs when atoms gain electrons?
They undergo a process called reduction.
True or False: Reduction involves a loss of electrons.
False.
Fill in the blank: Reduction is a chemical process involving a _______.
gain of electrons.
From where does the term ‘reduction’ originate?
The metal-refining industry.
Why is the term reduction expanded to include any reaction with electron gain?
Historically, it refers to reducing large amounts of ore to smaller amounts of pure metal.
What is an example of a reduction reaction?
Neutral atoms gain electrons to become ions
This occurs in processes where positive ions gain electrons to become neutral atoms.
What happens to positively charged ions during reduction?
They gain electrons to become neutral atoms
This process decreases their positive charge.
What does the mnemonic OIL RIG stand for?
Oxidation Is Loss; Reduction Is Gain
This helps remember the definitions of oxidation and reduction.
What is oxidation defined as?
The loss of electrons
This is a key concept in redox reactions.
What is reduction defined as?
The gain of electrons
Understanding this is essential in identifying redox reactions.
Fill in the blank: In a reduction reaction, neutral atoms gain _______ to become ions.
electrons
This describes the process of reduction in chemical reactions.
What occurs when negatively charged ions interact with neutral atoms?
They indicate a reduction process
This highlights the relationship between charges in redox reactions.
What happens to neutral atoms in the presence of positive ions during reduction?
They gain electrons to become negatively charged
This illustrates the electron transfer in reduction.
True or False: Reduction always involves the loss of electrons.
False
Reduction is characterized by the gain of electrons.
What is the balanced chemical reaction for the reaction between silver nitrate and solid zinc?
2AgNO₃(aq) + Zn(s) → Zn(NO₃)₂(aq) + 2Ag(s)
This equation shows the reactants and products of the reaction, indicating that zinc displaces silver from silver nitrate.
What happens to silver before and after the reaction?
Before reaction: Ag⁺(aq)
After reaction: Ag(s)
Silver starts as a cation in solution and is reduced to solid silver.
What type of reaction occurs for silver in this chemical process?
Reduction
Silver ions gain electrons to become solid silver.
What happens to zinc before and after the reaction?
Before reaction: Zn(s)
After reaction: Zn²⁺(aq)
Zinc starts as a solid and is oxidized to a cation in solution.
What type of reaction occurs for zinc in this chemical process?
Oxidation
Zinc loses electrons to become zinc ions.
Write the half-reaction for silver during the reaction.
2Ag⁺(aq) + 2e⁻ → 2Ag(s)
This half-reaction shows the reduction of silver ions to solid silver.
Write the half-reaction for zinc during the reaction.
Zn(s) → Zn²⁺(aq) + 2e⁻
This half-reaction demonstrates the oxidation of solid zinc to zinc ions.
True or False: In the reaction between silver nitrate and zinc, zinc is reduced.
False
Zinc is oxidized, not reduced.
Fill in the blank: The nitrate ion remains _______ during the reaction.
unchanged
The nitrate ion does not participate in the redox process.
What is the balanced chemical reaction for the reaction between silver nitrate and solid zinc?
2AgNO₃(aq) + Zn(s) → Zn(NO₃)₂(aq) + 2Ag(s)
This equation shows the reactants and products of the reaction, indicating that zinc displaces silver from silver nitrate.
What happens to silver before and after the reaction?
Before reaction: Ag⁺(aq)
After reaction: Ag(s)
Silver starts as a cation in solution and is reduced to solid silver.
What type of reaction occurs for silver in this chemical process?
Reduction
Silver ions gain electrons to become solid silver.
What happens to zinc before and after the reaction?
Before reaction: Zn(s)
After reaction: Zn²⁺(aq)
Zinc starts as a solid and is oxidized to a cation in solution.
What type of reaction occurs for zinc in this chemical process?
Oxidation
Zinc loses electrons to become zinc ions.
Write the half-reaction for silver during the reaction.
2Ag⁺(aq) + 2e⁻ → 2Ag(s)
This half-reaction shows the reduction of silver ions to solid silver.
Write the half-reaction for zinc during the reaction.
Zn(s) → Zn²⁺(aq) + 2e⁻
This half-reaction demonstrates the oxidation of solid zinc to zinc ions.
True or False: In the reaction between silver nitrate and zinc, zinc is reduced.
False
Zinc is oxidized, not reduced.
Fill in the blank: The nitrate ion remains _______ during the reaction.
unchanged
The nitrate ion does not participate in the redox process.
In the reaction discussed, was the silver oxidized or reduced?
The text does not specify the outcome for silver.
What type of reaction is involved in refining copper ore to produce pure copper?
Reduction
What is reduction in a chemical process?
A gain of electrons
If one substance undergoes reduction, what must happen to another substance?
It must lose electrons
In a chemical reaction, what must be analyzed to determine oxidation or reduction?
Each substance that participates in the reaction
Fill in the blank: Reduction involves a gain of _______.
electrons
True or False: Oxidation involves a gain of electrons.
False
What is the key process in refining copper ore?
Reduction
In the reaction discussed, was the silver oxidized or reduced?
The text does not specify the outcome for silver.
What type of reaction is involved in refining copper ore to produce pure copper?
Reduction
What is reduction in a chemical process?
A gain of electrons
If one substance undergoes reduction, what must happen to another substance?
It must lose electrons
In a chemical reaction, what must be analyzed to determine oxidation or reduction?
Each substance that participates in the reaction
Fill in the blank: Reduction involves a gain of _______.
electrons
True or False: Oxidation involves a gain of electrons.
False
What is the key process in refining copper ore?
Reduction
What is a single replacement reaction?
A reaction in which an element reacts with a compound to produce a new element and a new compound
Example: Zinc replacing silver ions in silver nitrate to produce solid silver.
What is a spectator in a chemical reaction?
An atom or polyatomic ion that does not change in a chemical reaction
Example: The nitrate ion in the reaction between zinc and silver nitrate.
In the reaction of zinc and silver nitrate, what was produced?
Solid silver
This occurs when zinc replaces silver ions in the silver nitrate.
True or False: In a single replacement reaction, both reactants change.
False
Only one element changes while the other remains a spectator.
Fill in the blank: A _______ is an atom or polyatomic ion that does not change in a chemical reaction.
[spectator]
Fill in the blank: A single replacement reaction produces a new _______ and a new _______.
[element], [compound]
What is a single replacement reaction?
A reaction in which an element reacts with a compound to produce a new element and a new compound
Example: Zinc replacing silver ions in silver nitrate to produce solid silver.
What is a spectator in a chemical reaction?
An atom or polyatomic ion that does not change in a chemical reaction
Example: The nitrate ion in the reaction between zinc and silver nitrate.
In the reaction of zinc and silver nitrate, what was produced?
Solid silver
This occurs when zinc replaces silver ions in the silver nitrate.
True or False: In a single replacement reaction, both reactants change.
False
Only one element changes while the other remains a spectator.
Fill in the blank: A _______ is an atom or polyatomic ion that does not change in a chemical reaction.
[spectator]
Fill in the blank: A single replacement reaction produces a new _______ and a new _______.
[element], [compound]
What is a redox reaction?
Reduction-oxidation reaction
Commonly shortened to redox reaction.
What occurs during oxidation?
Loss of electrons by an atom
This process results in the formation of ionic compounds.
What occurs during reduction?
Gain of electrons by an atom
This process allows for the extraction of metal ions from ores.
How are metal ions extracted from ores?
By giving the metal ions electrons
This process involves reduction.
What type of reactions can involve oxidation and reduction processes?
Single replacement reactions
One reactant gains electrons while another loses electrons.
What is a spectator ion?
An ion that does not lose or gain electrons
It remains unchanged during the reaction.
What is a redox reaction?
Reduction-oxidation reaction
Commonly shortened to redox reaction.
What occurs during oxidation?
Loss of electrons by an atom
This process results in the formation of ionic compounds.
What occurs during reduction?
Gain of electrons by an atom
This process allows for the extraction of metal ions from ores.
How are metal ions extracted from ores?
By giving the metal ions electrons
This process involves reduction.
What type of reactions can involve oxidation and reduction processes?
Single replacement reactions
One reactant gains electrons while another loses electrons.
What is a spectator ion?
An ion that does not lose or gain electrons
It remains unchanged during the reaction.
