chose 4 true statements.
a
The oxidation number of Bromine (Br) decreases.
b
The oxidation number of Bromine (Br) increases.
c
The oxidation number of Fluorine (F) decreases.
d
The oxidation number of Fluorine (F) increases.
e
Bromine (Br) undergoes oxidation.
f
Bromine (Br) undergoes reduction.
g
Fluorine (F) undergoes oxidation.
h
Fluorine (F) undergoes reduction.
To choose 4 true statements, we need to recall the definitions of oxidation and reduction in terms of oxidation numbers:
- Oxidation involves an increase in oxidation number.
- Reduction involves a decrease in oxidation number.
- Fluorine (F) is the most electronegative element and almost always has an oxidation number of -1 in its compounds. It typically does not increase in oxidation number because it's already at its lower state in compounds.
Based on these definitions:
a) If the oxidation number of Bromine (Br) decreases, that means it gains electrons and is reduced.
f) Bromine (Br) undergoes reduction - This statement is true if statement (a) is true.
b) If the oxidation number of Bromine (Br) increases, that means it loses electrons and is oxidized.
e) Bromine (Br) undergoes oxidation - This statement is true if statement (b) is true.
c) The oxidation number of Fluorine (F) decreases - This is unlikely to happen because fluorine is so electronegative and almost always has an oxidation number of -1.
h) Fluorine (F) undergoes reduction - Since the oxidation number of fluorine almost always remains at -1, it rarely, if ever, undergoes reduction, so this is typically false.
d) The oxidation number of Fluorine (F) increases - This is almost impossible because fluorine's oxidation state is almost always -1, and it cannot increase in typical chemical reactions.
g) Fluorine (F) undergoes oxidation - Because oxidation would imply an increase in oxidation number and fluorine is already at -1 (which cannot increase in normal chemical reactions), this is false.
So to choose 4 true statements, we need the context of a specific reaction to determine whether Bromine undergoes oxidation or reduction, because the oxidation states of fluorine are highly unlikely to increase due to its high electronegativity and typical oxidation state of -1.
However, without additional context, we cannot categorically choose 4 true statements from the list provided, because statements about the behavior of fluorine (c, d, g, and h) are generally false, and we do not have enough information to determine whether Bromine undergoes oxidation or reduction (a, b, e, and f).
If a specific reaction were given and we were able to see that Bromine is either gaining or losing electrons, then we could make a definitive choice. For instance, if Bromine were gaining electrons (being reduced), then a and f would be true, and if Bromine were losing electrons (being oxidized), then b and e would be true. But without that context, we cannot accurately select 4 true statements from this list.