A flask is filled with 50.0 ml of 0.15 M HCl acid. Exactly 0.054 grams of CaCo3 are placed in the acid, neutralizing some of it. How many moles of NaOH must be added in a titration that neutralizes the rest

of the acid?

See explanation

Explanation:

2HCl(aq) + CaCO3(aq) >CaCl2(aq) + CO2(g) + H2O(l)

Number of moles of acid present = 50/1000 * 0.15 = 0.0075 moles

Number of moles of calcium carbonate = 0.054g/100 g/mol = 0.00054 moles

2 moles of HCl reacts with 1 mole of calcium carbonate

x moles of HCl reacts with 0.00054 moles of calcium carbonate

x = 2 *  0.00054/1

x = 0.00108 moles of HCl

Amount of acid left = 0.0075 moles - 0.0075 moles = 0.00642 moles

Reaction of HCl and NaOH

HCl(aq) + NaOH(aq) > NaCl(aq) + H2O(l)

Since the reaction is in the mole ratio of 1:1

0.00642 moles of HCl is neutralized by 0.00642 moles of NaOH

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.