4. When Fe(NO3)3 is added to water, the following dissociation reaction occurs:
Fe(NO3)3 →
Fe3+ + 3 NO3
The Fe3+ is able to move freely through the H2O2 solution and catalyze the decomposition reaction.
Similarly, when Na3PO4 is added to water the following dissociation reaction occurs:
Na3PO4 → 3 Na+ + PO-.
When Fe3+ is combined with POS, an insoluble precipitate of FePO4(s) forms:
Fe3+ + POS- →
FePO4(s).
Why is Na3POs expected to act as an inhibitor for the catalyzed decomposition of H2O2 by Fe3+?

answer; i believe the correct answer is (solid gold);

answer: option (b) is the correct answer.

explanation:

a covalent bond is formed by sharing of electrons. whereas polarity arises due to difference in electronegativity of two atoms.

therefore, more is the electronegativity of an atom which combines with the titanium, more readily it will induce a partial positive and negative charge.

thus, out of the given options fluorine is most electronegative and has an incomplete octet. therefore, it will readily combine with titanium to share the electrons and complete its octet.  

d. temperate deciduous forest

tracks, burrows, eggshells, nests, tooth marks, or gastroliths