Question

Answer these post lab questions when given experimental data and procedures.

A REDOX TITRATION POST-LAB QUESTIONS LABORATORY 10 Name Date Section 1. Why can't the usual citration equation, MV. = MV be used asualtitration equation, MV M V.be used for this titration to get the moles of iron used: 2. Write the balanced chemical equation and label where the reduction and oxidation are occurring. 3. Using the chemical reaction, explain how the end point of the titration is detected.

Answer 1

Q 1)

Ans: The formula Ma.Va = Mb. Vb is use for the calculation of number of mole used in reaction.

While number of ions use in reaction can be bound by using Avagadros number.

The number of ions in 1 mole is given by the Avogadro Constant which is equal to 6.02x1023mol−1. We usually give this the symbol L.

So the solution in question contains L x M number of ions.

Q2)

Ans: The balance equation for the given reaction is 10FeSO4 + 2KMnO4 + 8H2SO4 = 5Fe2(SO4)3 + 2MnSO4 + K2SO4 + 8H2O

Fe+2 in the form of FeSO4 oxidise here to Fe+3 in the form of 5Fe2(SO4)3

Mn+6 in the form of KMnO4 Reduce in to Mn+2 in the form of MnSO4

Q3)

Ans:  And given the balanced chemical equation, you need some means to signal the end point of a titration, when a stoichiometric equivalence of titrant has been added to the analyte. an acid base indicator, which has distinct colours in acidic/base is used to indicate the end of the reaction.

And given the balanced chemical equation, you need some means to signal the end point of a titration, when a stoichiometric equivalence of titrant has been added to the analyte.

Q4)

Ans: Mnemonics meangs

LEO: loss of electrons is oxidation

GER: gain of electron is reduction

OIL: Oxidation is loss of electron

RIG: Reduction is Gain of electron

Q6)

Ans:

• Steps of Balancing a Chemical Equation

1. Identify each element found in the equation. The number of atoms of each type of atom must be the same on each side of the equation once it has been balanced.
2. What is the net charge on each side of the equation? The net charge must be the same on each side of the equation once it has been balanced.
3. If possible, start with an element found in one compound on each side of the equation. Change the coefficients (the numbers in front of the compound or molecule) so that the number of atoms of the element is the same on each side of the equation. Remember, to balance an equation, you change the coefficients, not the subscripts in the formulas.
4. Once you have balanced one element, do the same thing with another element. Proceed until all elements have been balanced. It's easiest to leave elements found in pure form for last.
5. Check your work to make certain the charge on both sides of the equation is also balanced.