Oxidation state of hydrogen is +1 in $H_2O$ while -1 in $CaH_2$.
$CaH_2$ is a metal hydride and for hydrides, hydrogen is assigned the oxidation number of -1.
- If both assertion and reason are true and reason is the correct explanation of assertion
- If both assertion and reason are true but reason is not the correct explanation of assertion
- If assertion is true but reason is false
- If both assertion and reason are false
The Correct Option is A
Solution and Explanation
Top Questions on Redox reactions
- Which of the following is a redox reaction, but not a combination reaction?
- CBSE Class X - 2024
- Science
- Redox reactions
- Identify the correct statement about the following reaction:
2H2S + SO2 → 2H2O + S- CBSE Class X - 2024
- Science
- Redox reactions
- MnO2 + 4HCl → MnCl2 + 2H2O + Cl2
The reaction given above is a redox reaction because in this case:- CBSE Class X - 2024
- Science
- Redox reactions
- The oxidation states not shown by Mn in the given reaction is:
\( 3MnO_4^{2-} + 4H^+ \rightarrow 2MnO_4^- + MnO_2 + 2H_2O \)
A. +6
B. +2
C. +4
D. +7
E. +3
Choose the most appropriate answer from the options given below:- NEET (UG) - 2024
- Chemistry
- Redox reactions
- Which of the following set of ions act as oxidising agents?
- NEET (UG) - 2024
- Chemistry
- Redox reactions
Questions Asked in AIIMS exam
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion (A) : 02 is liberated in the non-cyclic photophosphorylation.
Reason (R) : Liberation of oxygen is due to photolysis of water.
In the light of the above statements, choose the correct answer from the options given below
- AIIMS - 2019
- Photosynthesis in higher plants
- Match the following column I with column II.
- AIIMS - 2019
- cloning
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion (A) : The Cro-Magnon man was the direct ancestor of the living modern man.
Reason (R) : Cro-Magnon man had slightly prognathous face.
In the light of the above statements, choose the correct answer from the options given below
- AIIMS - 2019
- evolution
- Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion: Orbit of a satellite is within the gravitational field of earth whereas escaping is beyond the gravitational field of earth.
Reason: Orbital velocity of a satellite is greater than its escape velocity.
In the light of the above statements, choose the correct answer from the options given below- AIIMS - 2019
- Gravitation
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion (A) : In eukaryotes, transcription occurs in nucleus.
Reason (R) : In bacteria, transcription and translation occurs in cytoplasm.
In the light of the above statements, choose the correct answer from the options given below
- AIIMS - 2019
- Transcription
Concepts Used:
Redox Reactions
Redox Reaction:
Redox reactions are chemical reactions where oxidation and reduction take place simultaneously. In this type of reaction, there is a gain of electrons for one chemical species while the other loses electrons or simply involves transfer of electrons. The species that loses electrons is oxidized while the one that gains electrons is reduced.
Types of Redox Reactions:
Redox reactions can be differentiated into 4 categories namely combination reactions, decomposition reactions, displacement reactions, and disproportionation reactions. Each is explained separately below:
Combination Reaction:
In this, the molecules combine to form new compounds. For example, when magnesium reacts to nitrogen.
Decomposition Reaction:
Opposite to the combination reaction, here there is a breakdown of compounds to simpler substances. For example, electrolysis of water.
Displacement Reaction:
In this, the more reactive metal will displace the less reactive one in a chemical reaction. The reactivity of an element is represented in a series called the reactivity series (arranged in decreasing order of reactivity) which makes it easier to determine the chemical reaction and its products.
Disproportionation Reaction:
This is a peculiar type of reaction where an element showing a particular oxidation state will be oxidized and reduced simultaneously. Another thing to note is that these reactions will always have an element that can exhibit three oxidation states.