Discover Questions

Which bond is most polar?
C-Si ,O-Cl ,I-Br , As-Cl? Why is Quantum development so far behind? Technically speaking? How many different 4-digit numbers can be formed using the digits 2, 4, 5, 6, and 7 so that no digits repeat & the number is divisible by 4? What are cows? Is there any reaction from store bought ammonia and sugar (sucrose)? If so, a chemical equation would be appreciated.
NH4 + C12H22O11?