Answer: The standard free energy change for a reaction in an electrolytic cell is always positive.
Explanation:
Electrolytic cells use electric currents to drive a non-spontaneous reaction forward.
Relation of standard free energy change and emf of cell

where,
 = standard free energy change
 = standard free energy change 
   n= no of electrons gained or lost
F= faraday's constant
 = standard emf
 = standard emf
 = standard emf = -ve  , for non spontaneous reaction
   = standard emf = -ve  , for non spontaneous reaction
Thus  
Thus standard free energy change for a reaction in an electrolytic cell is always positive.
 
        
             
        
        
        
The mass of magnesium, which has a density of 1.74 g/cm is 504.6 g.
<h3>What is mass?</h3>
Mass is the quantity of matter. Mass can be calculated by multiplying density by volume.
Magnesium is a chemical element with the atomic number 12. It is needed in the body in trace amounts. It can cause malnutrition in the body.
Mass = Density x volume
We know the density and the volume of magnesium. 
Density = 1.74
Volume = 290
Density x volume
Putting the value in the equation
1.74 x 290 = 504.6 g
Thus, the mass of magnesium is 504.6 g.
To learn more about mass, refer to the below link:
brainly.com/question/22795877
#SPJ1
 
        
             
        
        
        
<span>The mass of one mole of sodium bicarbonate (aka NaHCO3) is equal to 1 * 22.99g/mol + 1 * 1.00g/mol + 1 * 12.01g/mol + 3 * 16.00g/mol = 83.91g/mol. From this, we can convert 4.2g of NaHCO3 to moles by dividing by 83.91g/mol, to get 0.050 moles of sodium bicarbonate.</span>