Gen Chem I Redox Reactions and Oxidation Numbers
34 flashcards covering Gen Chem I Redox Reactions and Oxidation Numbers for the GENERAL-CHEMISTRY-1 Gen Chem I Topics section.
Redox reactions and oxidation numbers are fundamental concepts in General Chemistry I, as defined by the American Chemical Society's guidelines. This topic encompasses the identification of oxidation states, the balancing of redox reactions, and the understanding of electron transfer processes. Mastery of these concepts is crucial for students, as they form the basis for more advanced chemical principles and reactions encountered in various scientific fields.
On practice exams and competency assessments, questions often require students to identify oxidation states in complex molecules or balance redox equations. Common traps include misidentifying oxidation states in transition metals or overlooking the need to balance both mass and charge in redox reactions. Students may also struggle with the distinction between oxidation and reduction processes, leading to errors in determining the correct half-reactions. A practical tip to keep in mind is to always double-check your work by ensuring that both the number of atoms and the total charge are balanced in your final equation.
Terms (34)
- 01
What is the oxidation state of sulfur in H2SO4?
The oxidation state of sulfur in H2SO4 is +6, as calculated by balancing the charges of the hydrogen and oxygen atoms in the molecule (Zumdahl, Chapter on Redox Reactions).
- 02
How do you determine the oxidation number of an element in a compound?
To determine the oxidation number of an element, assign oxidation states based on known rules, such as the oxidation state of oxygen being -2 and hydrogen being +1, and ensure the sum equals the overall charge of the compound (Brown LeMay, Chapter on Oxidation States).
- 03
What is the oxidation state of chlorine in NaClO3?
The oxidation state of chlorine in NaClO3 is +5, determined by balancing the oxidation states of sodium (+1) and oxygen (-2) in the compound (Tro, Chapter on Redox Reactions).
- 04
Which of the following is a reduction reaction?
A reduction reaction is characterized by the gain of electrons or a decrease in oxidation state, such as the conversion of Cu^2+ to Cu (Brown LeMay, Chapter on Redox Reactions).
- 05
What is the oxidation state of carbon in CH4?
The oxidation state of carbon in CH4 is -4, as it is bonded to four hydrogen atoms, each contributing +1, resulting in a total of +4 that balances the overall charge of the molecule (Zumdahl, Chapter on Oxidation Numbers).
- 06
How often must a redox reaction be balanced?
A redox reaction must always be balanced in terms of both mass and charge before proceeding with calculations or predictions of products (Tro, Chapter on Balancing Redox Reactions).
- 07
What is the oxidation number of nitrogen in NH4+?
The oxidation number of nitrogen in NH4+ is -3, determined by balancing the +1 charges from four hydrogen atoms against the overall +1 charge of the ammonium ion (Brown LeMay, Chapter on Oxidation States).
- 08
When balancing redox reactions, what is the first step?
The first step in balancing redox reactions is to separate the half-reactions for oxidation and reduction, allowing for independent balancing of each process (Tro, Chapter on Balancing Redox Reactions).
- 09
What is the oxidation state of manganese in KMnO4?
The oxidation state of manganese in KMnO4 is +7, calculated by considering the potassium (+1) and four oxygen atoms (-8) in the compound (Zumdahl, Chapter on Oxidation Numbers).
- 10
What indicates a substance is oxidized in a redox reaction?
A substance is oxidized in a redox reaction when it loses electrons, resulting in an increase in its oxidation state (Brown LeMay, Chapter on Redox Reactions).
- 11
What is the oxidation state of iron in Fe2O3?
The oxidation state of iron in Fe2O3 is +3, as the total oxidation state from three oxygen atoms (-6) must be balanced by two iron atoms (each +3) (Tro, Chapter on Oxidation States).
- 12
Which of the following represents a reduction process?
A reduction process is represented by the gain of electrons, such as the conversion of Ag+ to Ag (Brown LeMay, Chapter on Redox Reactions).
- 13
What is the oxidation state of phosphorus in H3PO4?
The oxidation state of phosphorus in H3PO4 is +5, determined by balancing the contributions from three hydrogens (+3) and four oxygens (-8) (Zumdahl, Chapter on Oxidation Numbers).
- 14
How can you identify the reducing agent in a redox reaction?
The reducing agent can be identified as the substance that donates electrons and is oxidized in the process (Tro, Chapter on Redox Reactions).
- 15
What is the oxidation state of oxygen in peroxides?
In peroxides, the oxidation state of oxygen is -1, differing from its usual -2 state in most compounds (Brown LeMay, Chapter on Oxidation States).
- 16
What happens to the oxidation state of an element during oxidation?
During oxidation, the oxidation state of an element increases as it loses electrons (Tro, Chapter on Redox Reactions).
- 17
What is the oxidation state of chromium in Cr2O7^2-?
The oxidation state of chromium in Cr2O7^2- is +6, determined by balancing the charges of the seven oxygen atoms (-14) with the overall charge of -2 (Zumdahl, Chapter on Oxidation Numbers).
- 18
What is the role of a reducing agent in a redox reaction?
The role of a reducing agent in a redox reaction is to donate electrons to another species, causing that species to be reduced while itself is oxidized (Brown LeMay, Chapter on Redox Reactions).
- 19
How do you assign oxidation numbers to a polyatomic ion?
To assign oxidation numbers to a polyatomic ion, sum the oxidation states of all atoms to equal the overall charge of the ion (Tro, Chapter on Oxidation States).
- 20
What is the oxidation state of zinc in ZnCl2?
The oxidation state of zinc in ZnCl2 is +2, as it balances the -1 charge from two chloride ions (Brown LeMay, Chapter on Oxidation States).
- 21
What does it mean if a substance is reduced in a redox reaction?
If a substance is reduced in a redox reaction, it means it has gained electrons, resulting in a decrease in its oxidation state (Tro, Chapter on Redox Reactions).
- 22
What is the oxidation state of iodine in I2?
The oxidation state of iodine in I2 is 0, as it is in its elemental form (Brown LeMay, Chapter on Oxidation States).
- 23
How can you tell if a reaction is a redox reaction?
A reaction is a redox reaction if there is a transfer of electrons between species, indicated by changes in oxidation states (Tro, Chapter on Redox Reactions).
- 24
What is the oxidation state of sulfur in SO2?
The oxidation state of sulfur in SO2 is +4, calculated by balancing the oxidation states of the two oxygen atoms (-4) with the overall charge of the molecule (Zumdahl, Chapter on Oxidation Numbers).
- 25
What is the oxidation state of nitrogen in NO3-?
The oxidation state of nitrogen in NO3- is +5, determined by balancing the three oxygen atoms (-6) with the overall charge of -1 (Brown LeMay, Chapter on Oxidation States).
- 26
What is the oxidation state of potassium in K2Cr2O7?
The oxidation state of potassium in K2Cr2O7 is +1, as it balances the overall charge of the dichromate ion (Tro, Chapter on Oxidation States).
- 27
What is the oxidation state of carbon in CO2?
The oxidation state of carbon in CO2 is +4, as it balances the two oxygen atoms (-4) in the molecule (Brown LeMay, Chapter on Oxidation States).
- 28
What must be true for a redox reaction to occur?
For a redox reaction to occur, there must be a transfer of electrons between two species, resulting in changes in oxidation states (Tro, Chapter on Redox Reactions).
- 29
What is the oxidation state of aluminum in Al2O3?
The oxidation state of aluminum in Al2O3 is +3, as it balances the three oxygen atoms (-6) in the compound (Zumdahl, Chapter on Oxidation Numbers).
- 30
What is the oxidation state of lead in PbO2?
The oxidation state of lead in PbO2 is +4, calculated by balancing the two oxygen atoms (-4) with the overall charge of the molecule (Brown LeMay, Chapter on Oxidation States).
- 31
What is the oxidation state of copper in CuSO4?
The oxidation state of copper in CuSO4 is +2, determined by balancing the sulfate ion's charge (-2) with copper's oxidation state (Tro, Chapter on Oxidation States).
- 32
What indicates a substance is reduced in a redox reaction?
A substance is reduced in a redox reaction when it gains electrons, resulting in a decrease in its oxidation state (Brown LeMay, Chapter on Redox Reactions).
- 33
What is the oxidation state of selenium in H2Se?
The oxidation state of selenium in H2Se is -2, as it is bonded to two hydrogen atoms, each contributing +1 (Zumdahl, Chapter on Oxidation Numbers).
- 34
How do you identify the oxidizing agent in a redox reaction?
The oxidizing agent can be identified as the substance that accepts electrons and is reduced in the process (Tro, Chapter on Redox Reactions).