Question

its a two part question. plz look at second pic

BA 3A 4A 5A 6A 7A He 27 Na Mg 3B 4B 5B 6B7B 8B1B2B K ca sa Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd Hf Ta W Re Os Ir Pt Au Hg At Rn TI Ra AC Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu FE Ni Pu Am Cm 12 covalent bond(s) in order to The element selenium would be expected to form obey the octet rule. Use the octet rule to predict the forntula of the compound that would form between selenium and hydrogen , if the molecule contains only one selenium atom and only single bonds are formed. Formula: Submit Answer Retry Entire Group 9 more group attempts remaining

Answer 1

In part first the Selenium has 6 valence electrons in its valence shell so for completing the octet rule it must need 2 electrons so since one covalent bond means one electron sharing so Selenium will form 2 Covalent Bonds.

Since Hydrogen can only single bond that's means two hydrogen is required and in molecule only one Selenium atom is Present than formula will be H2Se

In second part

Sulphur has 6 valence electrons in its valence shell so it needs two electron to complete its octet so it will form 2 Covalent Bonds.

By using octet rule since molecule contain only 1 sulphur atom and hydrogen can only form 1 Covalent bond so formula of the molecule will be H2S