From electronic configuration valence electron of Nitrogen is 5, oxygen 6x2 which 12 since it involve two molecules , that of is frulorine is 7, and that No2F is 24 which is gotten form adding (5,12,7 ).All resonance structure are as follows
F
.. I ..
: O : N :O:
..
OR : F:
I
N .. : F:
/ \ or I
.. .. N
:O : :O: / / \\
/ / \\
:O : : O:
The method of determining the most common isotope of lead is by determining the average atomic mass. The formula for determining the average atomic mass is:
Substituting the values in the formula:
The most common isotope of lead is:
Lead - 207.22 amu
The atomic symbol of lead is 
. The atomic number of is 82.
So, the the most common isotope of lead can be written as:
and Lead - 207.22 amu.
For #7, both hydrogen and oxygen are nonmetals, making it not A,
B would be the correct answer
For #8, chemical properties is the characteristic of a substance observed in a chemical reaction, A and B would be physical. C would be correct
hope this helped
Answer:
The law of conservation of mass states that matter cannot be created or destroyed in a chemical reaction.
For example, when wood burns, the mass of the soot, ashes, and gases equals the original mass of the charcoal and the oxygen when it first reacted. So the mass of the product equals the mass of the reactant.
Another example, solar panels don't create solar energy. They harness energy from the sun and transform it into another type of energy (electricity).
