If all the reactants will react and become products, the mass will be 12.5 g. Because the mass of the matter amount will not change during the reaction.
        
             
        
        
        
The atomic mass is the average of the isotopes of the element meaning most averages of isotopes will not be whole numbers
        
             
        
        
        
The correct answer for the question that is being presented above is this one: "A. The accepted model of the atom was changed.<span>" </span>J J Thomson discovered the electrons and performed experiment using the cathode ray tube
Here are the following choices:
<span>A. The accepted model of the atom was changed.
B. The accepted model of the atom was supported.
C. Cathode ray tubes were no longer used in experiments due to poor results.
D. Cathode ray tubes became the only instrument of use in the study of atoms</span>
        
             
        
        
        
The number of C atoms in 0.524 moles of C is 3.15 atoms.
The number of  molecules in 9.87 moles
 molecules in 9.87 moles   is 59.43 molecules.
 is 59.43 molecules.
The moles of Fe in 1.40 x  atoms of Fe is 0.23 x
 atoms of Fe is 0.23 x 
The moles of  in 2.30x
 in 2.30x molecules of
 molecules of  is 3.81.
 is 3.81.
<h3>What are moles?</h3>
A mole is defined as 6.02214076 ×  of some chemical unit, be it atoms, molecules, ions, or others. The mole is a convenient unit to use because of the great number of atoms, molecules, or others in any substance.
 of some chemical unit, be it atoms, molecules, ions, or others. The mole is a convenient unit to use because of the great number of atoms, molecules, or others in any substance.
A. The number of C atoms in 0.524 mole of C:
 6.02214076 ×  x 0.524 mole
 x 0.524 mole 
3.155601758 atoms =3.155 atoms
B. The number of  molecules in 9.87 moles of
 molecules in 9.87 moles of  :
:
6.02214076 ×  x 9.87
 x 9.87
59.4385293 molecules= 59.43 molecules
C. The moles of Fe in 1.40 x  atoms of Fe:
 atoms of Fe:
1.40 x  ÷ 6.02214076 ×
 ÷ 6.02214076 × 
0.2324754694 x  moles.
 moles.
0.23 x  moles.
 moles.
D. The moles of  in 2.30x
 in 2.30x molecules of
 molecules of  :
:
2.30x ÷ 6.02214076 ×
 ÷ 6.02214076 × 
3.819239854 moles=3.81 moles
Learn more about moles here:
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