AP EAMCET · Chemistry · Redox Reactions
The oxidation number of an element in a compound is evaluated on the basis of certain rules. Which of the following rules is not correct?
1. The oxidation number of hydrogen is always +1.
2. The algebraic sum of all the oxidation numbers of all elements in a compound is zero.
3. An element in the free or the uncombined state bears oxidation number zero.
4. In all its compounds, the oxidation number of fluorine is -1.
- A 1
- B 2
- C 3
- D 4
Answer & Solution
Correct Answer
(A) 1
Step-by-step Solution
Detailed explanation
Oxidation number of hydrogen is usually +1 compounds with more electrongative atoms (as in \(\mathrm{H}_2 \mathrm{O}\)) is +1. But in alkali metal hydride like lithium hydride of the molecule where the oxidation state of hydrogen atom \(=-1\)
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