Answer:
the periodic table is important because it is organized to provide a alot of information about elements and how they relate to one another in one easy-to-use reference. The table can be used to predict the properties of elements, even those that have not yet been discovered.
Explanation:
In a chemical reaction, the equilibrium constant refers to the value of its reaction quotient at chemical equilibrium, that is, a condition attained by a dynamic chemical system after adequate time has passed, and at which its composition has no measurable capacity to undergo any kind of further modification.
The given reaction is: HCN (aq) + OH⁻ = CN⁻ (aq) + H2O (l)
The equilibrium constant = product of concentration of products / product of concentration of reactants
(Here, H2O is not considered as its concentration is very high)
So, Keq = [CN⁻] / [HCN] [OH⁻]
Answer: 34.4 g
Explanation:
As 
is in excess, 
is the limiting reagent and thus it will limit the formation of products.
According to stoichiometry:
2 moles of hydrogen produce = 1 mole of 
2.5 moles of hydrogen produce = 
of
Mass of 
But as % yield is 86%, mass of produded is 
Thus 34.4 g of is produced.
