Response:
The pKa value is 13.0.
Clarification:
pKa + pKb = 14
For trimethylamine, Kb = 6.3 ×
Calculating pKb: pKb = - log (6.3 × )
= 1.0
Thus, pKa = 14 - pKb = 14 - 1.0
pKa = 13.0
Verification: The typical range for pKa in weak acids is from 2 to 13.
Answer:
Explanation:
Diethyl malonate possesses greater acidity compared to monocarbonyl substances (pKa=13) because its alpha hydrogens are linked to two carbonyl groups. Consequently, the malonic ester can be readily changed into its enolate ion by reacting it with sodium ethoxide in ethanol. When the malonic ester undergoes alkylation, a hydrogen atom in the alpha position becomes acidic, permitting another round of alkylation to yield a dialkylated malonic ester.
In this scenario, when diethyl malonate interacts with urea in the presence of sodium ethoxide base, the second alkylation step occurs within the molecule, producing a cyclic compound known as barbituric acid.
84.34 grams of iron (III) chloride is the maximum produced since iron is the limiting reagent, and chlorine gas is in excess.
Explanation:
Balanced equation:
2 Fe + 3 Cl2 → 2 FeCl3
DATA PROVIDED:
iron = atoms
mass of chlorine = 67.2 liters
mass of FeCl3 =?
The number of moles of iron will be calculated as
number of moles =
number of moles =
number of moles = 0.52 mol of iron
moles of chlorine gas
number of moles =
Substituting the values into the equation:
n = (molar mass of chlorine gas = 70.96 g/mol)
= 947.01 moles
As iron is the limiting reagent therefore
2 moles of Fe lead to 2 moles of FeCl3
0.52 moles of Fe will yield
=
0.52 moles of FeCl3 is produced.
To express this in grams:
mass = n x molar mass
= 0.52 x 162.2 (molar mass of FeCl3 is 162.2g/mol)