To balance this equation, first we should consider balancing C because it only presents in one reactant and one product. Assuming the coefficient of C6H6 is 1, there are 6 C's in the reactant, so it generates 6CO2. Then consider balancing H for the same reason. If the coefficient of C6H6 is 1, there are 6 H's in the reactant, so it generates 3H2O.
Now that the coefficient of the products are determined, we can balance O. There are 6*2=12 O's in CO2 and 3*1=3 O's in H2O. So the total number of O in the products is 12+3 = 15. O2 is the only reactant that contains O, so to balance the equation, the coefficient of O2 should be 15/2.
Now the equation looks like:
C6H6 + 15/2O2 ⇒ 6CO2 + 3H2O.
Times both sides of the equation by 2 results the final answer:
2C6H6 + 15O2 ⇒ 12CO2 + 6H2O
20 g O2 x 1 mol O2/32 g O = 0.625 mol O2
Answer:
Base Mg(OH)2 does neutralise the acid and is 12g in excess.
Explanation:
2HCL +Mg(OH)2 -> MgCl2 + 2H20
2 * 36.458 g of HCL react with 58.319 g of Mg(OH)2 to neutralise it.
72.916 HCl reacts with 58.319 g of the base.
So 20 g HCl reacts with (58.319/72.916) * 20 = 16g.
There are 28 g of Mg(OH)2 so the base does neutralise all the acid.
The Mg(OH)2 is 28 - 16 = 12 g in excess.