Answer:
c) 30
Explanation:
In an atom , the relation between the subatomic particles of the atom are given as follows -
For a neutral atom ,
Atomic number = number of protons = number of electrons ,
Mass number = number of protons + number of neutrons,
Hence , from the given information of the question,
Atomic number of Manganese = 25 ,
mass number of Manganese = 55 ,
Now, to calculate the number of neutrons , the above relation can be used -
Mass number = number of protons + number of neutrons,
Rearranging ,
number of neutrons = Mass number - number of protons
substituting the respective values ,
number of neutrons = 55 - 25 = 30 .
It has 4 valence electron, all of which are needed to bond with nearest neighbors
The Percent error in the calculation of densities of the metal during experiment is 0.03 %
<h3>What is Percentage error?</h3>
Percent error is the difference between estimated value and the actual value in comparison to the actual value and is expressed as a percentage.
Percent error = [Experimental value - Theoretical value] / Theoretical value x 100%
Percent error = 7.83 -7.86 / 7.86 x 100
= 0.03 %
Learn more about percentage error here ;
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You can reduce the charges and subscripts so it is PbS2
