Consider the equation A(aq) 2B(aq) 3C(aq) 2D(aq). In one experiment, 45.0 mL of 0.050 M A is mixed with 25.0 mL 0.100 M B. At equilibrium the concentration of C is 0.0410 M. Calculate K. g

K = 0.0396

Explanation:

Based on the reaction:

A + 2B ⇄ 3C + 2D

Where equilibrium constant, K, is:

K = [C]³[D]² / [A] [B]²

The initial concentrations of A and B are:

[A]₀ = 0.050M * (45.0mL / 70.0mL) = 0.0321M

[B]₀ = 0.100M * (25.0mL / 70.0mL) = 0.0357M

As [C] = 0.0410M, the molar concentration of D is:

0.0410M * (2mol D / 3mol C) = 0.0273M = [D]

And the concentration of A and B that reacted was:

0.0410M * (2mol B / 3mol C) = 0.0273M B

0.0410M * (1mol A / 3mol C) = 0.0137M A

Equilibrium concentration B and A:

0.0357M - 0.0273M = 0.0084M = [B]

0.0321M - 0.0137M = 0.0184M = [A]

And K is:

K = [0.0410M]³[0.0273M]² / [0.0184M] [0.0084M]²

c-14 is carbon-14, or radiocarbon.   it is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons.

definition

                    entropy is a measure of the randomness or the extent of disorder of a chemical process.

                      enthalpy is a measure of the heat change of a reaction occurring at a constant pressure.

measurement units:

                        entropy is measured in joule per kelvin (jk⁻¹)   whereas enthalpy is measured in joule per mole (jmol⁻¹)

requirements:

                            entropy has no requirements or limits, and its change is measured by the division between the heat change of the chemical process and the temperature.

                              in contrast, enthalpy can only be related to the heat change of the reaction under standard conditions.