Answer:
<u>The answer is</u>: <em>B. </em><em>Energy lost to the environment during the reaction must be replaced.</em>
Explanation:
 
        
             
        
        
        
Either give off or gain electrons to make a total of 8
 
        
             
        
        
        
<h3>Answer:</h3>
                        2.55 × 10²² Na Atoms
<h3>Solution:</h3>
Data Given:
                  M.Mass of Na  =   23 g.mol⁻¹
                  Mass of Na  =  973 mg  =  0.973 g
                  # of Na Atoms  =  ??
Step 1: Calculate Moles of Na as:
                Moles  =  Mass ÷ M.Mass
                Moles  =  0.973 g ÷ 23 g.mol⁻¹
                Moles  =  0.0423 mol
Step 2: Calculate No, of Na Atoms as:
As 1 mole of sodium atoms counts 6.022 × 10²³ and equals exactly to the mass of 23 g. So, we can write,
                Moles  =  No. of Na Atoms ÷ 6.022 × 10²³ Na Atoms.mol⁻¹
Solving for No. of Na Atoms,
                No. of Na Atoms  =   Moles × 6.022 × 10²³ Na Atoms.mol⁻¹
                No. of Na Atoms  =   0.0423 mol × 6.022 × 10²³ Na Atoms.mol⁻¹
                No. of Na Atoms  =  2.55 × 10²² Na Atoms
<h3>Conclusion: </h3>
                           2.55 × 10²² sodium atoms are required to reach a total mass of 973 mg in a substance of pure sodium.
 
        
             
        
        
        
It’s gas because the molecules are moving quicker.