16 Which of the following bonds is weakest 17 Alkali metals

16. Which of the following bonds is weakest? 17. Alkali metals (Group 1A) have low first ionization energies because (a) losing one electron will make them isoelectronic with the nearest noble gas. (b) losing two electrons will make them isoelectronic with the nearest noble gas. (c) gaining one electron will give them a full valence shell. (d) gaining two electrons will make them isoelectronic with the nearest noble gas (e) alkali metals have very high first ionization energies. 18. What is the highest (most positive) possible oxidation number of selenium (Se)? (a) -2 (b) 0 (c) +1 (d) +6 (e) +7

Solution

16. Answer is e) C-I

Iodine atomic size is high and carbon is small in atomic size. Easily can cleave the bond.

17. Answer is a)

18. Highest possible oxidation number is +6

Se is belongs to 6th group..Electronic configuration is ns2 np4