Which of the following would lead to the highest entropy gain in the surroundings? A. An endothermic reaction in a hot environment.
B. An exothermic reaction in a cold environment.
C. An exothermic reaction in a hot environment
D. An endothermic reaction in a cold environment.

B. An exothermic reaction in a cold environment.

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.  

elements make up everything, and they combine to make compounds.

the answer is c