Iron(II) can be oxidized by an acidic K2Cr2O7 solution according to the net ionic equation: Cr2O7 2- +6Fe2+ + 14H+>2Cr3+ + 6Fe3+ + 7H20
If it takes 40.5 mL of 0.0250 M K2Cr2O7, to titrate 25.0 mL of a solution containing Fe2+, what is the molar concentration of Fe2+ in the original solution?

the atomic mass is the bottom number on the element.

-steel jelly

the correct answer is b. a strong acid completely dissociates to its ions when dissolved in water. completely dissociates to and ions. a is incorrect because does not fully ionize to and ions and some remain as the compound . c and d are incorrect because, and do not fall into the category of bronsted lowry acids. a bronsted lowry acid is a proton donor and since both molecules do not have a proton to donate they are not bronsted lowry acids. likewise,   if we use the lewis acid definition, they cannot be acids. a lewis acid is an electron pair acceptor. both and have a complete octet so can not accept any electrons which disqualifies them as acids.

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.