Answer:
NO2- is the reducing agent.
Cr2O7_2- is the oxidizing agent.
H+ is neither
Explanation:
Reduction is the gain in electron. A chemical specie that undergoes reduction is called the oxidizing agent.
Oxidation is simply the loss in electrons. A chemical specie that undergoes oxidation is called the reducing agent.
Let us look at the species.
The first specie is the NO2-. In this specie, the oxidation number of nitrogen changed from +3 to +5 in NO3-. Thus we can see that there is more loss of electron to have caused an increase in the oxidation number positively. This shows an oxidation. Hence, NO2- is the reducing agent.
Let us look at the chromium. We can see that the oxidation number of chromium changed from +7 to +3.
Now we can see that it is a decrease and hence, it is a gain of electron and thus it is reduction. This means the first chromium specie is the oxidizing agent.
The hydrogen ion is simply placed there to balance the ions and hence it is neither the oxidizing nor the reducing agent.
Answer:
I think the answer would be b, sorry if I'm wrong(EDIT: ITS ACTUALLY AAAAA)
Answer:

Explanation:
Here, we wnat to get the most electronegative atom
On the periodic table, electronegativity increases across a period and decrease down the group
The elements listed are in the same group
Boron is the first member of the group
Boron is the most electronegative atom in the group
Yes it is, because lucid means characterized by clear perception.
Organic chemistry present for a substance