Physical Chemistry Answers

sketch a graph to show the successive ionization energies of Fluorine

Give reasons for the shape of your graph.

Define the second ionization energy of Fluorine.

ii. Write an equation to represent the second ionization energy of Fluorine.

Give two conditions necessary for the formation of a dative bond.

Draw the shape of a molecule of a named compound (or species) which has the bond angle indicated: A. 109.50 B. 1200 C.1050

ii) Explain the differences in shape between the molecules A and B above.

What do you understand by bond energy term?

ii) Use the following to calculate the C−H and 𝐶−𝐶 bond energies.

C2H6(g) yields 2C(g) + 6H(g) Δ𝐻∶282 𝐾𝐽𝑚𝑜𝑙−1

C3H6(g) yields 3C(g) + 8H(g) Δ𝐻∶3996 𝐾𝐽𝑚𝑜𝑙−1

A standard solution of hydrated Iron (II) sulphate, FeSO4.xH2O, as prepared by dissolving 5.8g of the salt in a volumetric flask making it to 250ml (250 cm3), 25ml (25 cm3) of this solution was acidified and found to react with 22.8ml (22.8 cm3) of 0.018MPotassium permanganate solution.

Calculate:

i) the molar mass of the salt.

ii) The value of x, the number of molecules of the water of crystallization.

A standard solution of hydrated Iron (II) sulphate, FeSO4.xH2O, as prepared by dissolving 5.8g of the salt in a volumetric flask making it to 250ml (250 cm3), 25ml (25 cm3) of this solution was acidified and found to react with 22.8ml (22.8 cm3) of 0.018MPotassium permanganate solution.

Calculate:

i)The concentration (moldm3) of the Iron(II) salt

ii)The number of moles of the salt in 250 cm3 of solution.

A standard solution of hydrated Iron (II) sulphate, FeSO4.xH2O, as prepared by dissolving 5.8g of the salt in a volumetric flask making it to 250ml (250 cm3), 25ml (25 cm3) of this solution was acidified and found to react with 22.8ml (22.8 cm3) of 0.018MPotassium permanganate solution.

i) What is the indicator for the titration of Iron(II)sulphate and Potassium permanganate solution?

ii)indicate the colour at the end point if the permanganate is in the burette.

iii)Why is it necessary to acidify the Iron(II)sulphate before titration ?

What is i) a standard solution? ii)a reduction-oxidation (redox) reaction?