If a student has 450mL of a 3.2M HCl solution and wants the molarity to be 0.85M, what volume do they need to dilute it to? Show all work to receive full credit.

1.694 L

Explanation:

First, solve for the number of moles of HCl in a 450-ml 3.2M solution:

# of mol HCl = (3.2 mol HCl/L)(0.450 L)

= 1.44 mol HCl

The molarity M is given by

M = (# of moles)/(volume in L)

Solving for the volume,

V = (# of moles)/M

= (1.44 mol HCl)/(0.85M)

= 1.694 L

Therefore, the 3.2M HCl solution must be diluted until its volume becomes 1.694 L.

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.