The balanced equation for the reaction between Mg and O₂ is as follows
2Mg + O₂ --> 2MgO
stoichiometry between Mg and O₂ is 2:1
number of Mg reacted - 4.00 mol
if 2 mol of Mg reacts with 1 mol of O₂
then 4.00 mol of Mg requires - 1/2 x 4.00 = 2.00 mol of O₂
then the mass of O₂ required - 2.00 mol x 32.0 g/mol = 64.0 g
64.0 g of O₂ is required for the reaction
<span>an electrolytic cell</span>
Mass of object A = 10g
volume of object A = 8cm³
Mass of object B = 10g
Volume of Object B = 6cm³
we use the following formula to calculate the density of object A and B.
Density = Mass / Volume
Density of Object A = 10g / 8cm³ = 1.25g/cm³
Density of Object B = 10g / 6cm³ =1.67 g/cm³
So the density of object B is greater than object A
and if we find the difference:
1.67 - 1.25 = 0.42
So the answer is; Object B, by 0.42 gram per cubic centimeter