It simply equals 4x-16.......
the expression is in lowest terms, so you can’t do anything else
        
                    
             
        
        
        
All of the questions here are pertaining to the colligative properties of a solution and the preparation of solutions. Maybe, it would be best if you understand the equations to be used in order to answer these questions.<span>
Freezing point depression or Boiling point elevation:
</span><span>ΔT = -K (m) (i)
</span>ΔT is the change in the freezing point or the boiling point not the freezing point/boiling point. Therefore, it should be added to the original value of the property of the solvent. 
<span>
K is a constant called the molal freezing point depression constant and for the boiling point is the boiling point elevation constant. It is a property of the solvent. 
</span><span>
m is the concentration of the solute in the solvent in terms of molality or kg solute/kg solvent. 
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i is the vant hoff factor which will represent the number of ions which the solute dissociates when in solution.</span>
        
             
        
        
        
Answer:
The answer to your question is below
Explanation:
a) 
Number of atoms = ?
moles of Fe = 4.75
-Use proportions to solve this problem
                             1 mol of Fe --------------------- 6.023 x 10²³ atoms
                           4.75 moles  ---------------------  x
                             x = (4.75 x 6.023 x 10²³) / 1
                             x = 2.86 x 10²⁴ / 1
   Number of atoms = 2.86 x 10²⁴ 
b) 
Number of moles = ?
moles of 1.058 moles of H₂O
I think this question is incorrect, maybe you wish to know the number of atoms or grams of H₂O.
c) 
Number of atoms = ?
moles of Fe = 0.759 
                        1 mol of Fe ------------------ 6.023 x 10²³ atoms
                        0.759 moles ---------------  x
                         x = (0.759 x 6.023 x 10²³) / 1
                         x = 4.57 x 10²³ / 1
Number of atoms of Fe = 4.57 x 10²³ atoms
d) 
Number of molecules = ?
moles of H₂O = 3.5 moles
                           1 mol of H₂O ------------------ 6.023 x 10²³ molecules
                          3.5 moles       ------------------   x
                           x = (3.5 x 6.023 x 10²³) / 1
                           x = 2.11 x 10²⁴ molecules
Number of molecules = 2.11 x 10²⁴                                                                         
 
        
             
        
        
        
D. Changes
Hope this helps :)
        
             
        
        
        
Because mass is not always the same for objects made from the same material. Just because an object has the same mass as another doesn’t mean they are the same material.