Elements X, Y and Z have 4, 5 and 7 valence electrons respectively.
(i) Write the molecular formula of the compounds formed by these elements individually with hydrogen.
(ii) Which of these compounds will have the highest dipole moment?
(i); XH4, H3Y, and HZ
Hydrogen has only one electron in its outermost shell it shares one electron to form a covalent bond or accepts or donates one electron to form an ionic bond.
For XH4, the X element requires 4 electrons to complete its octet so 4 hydrogen atoms will form a covalent bond with X similarly for element Y 3 atoms of Hydrogen will form a covalent bond to form compound HY3.
For HZ, the bond will be ionic in nature hydrogen will donate one electron to form cation and Z will accept one electron to form anion and both of them will form an ionic bond.
(ii); The compound HZ has a linear shape and the difference in the electronegativity of Hydrogen and element Z is maximum.
Z has maximum electronegativity due to the small atomic radius and greater nuclear charge.