P BLOCK (2) 15 and 16 Flashcards
Molecular nitrogen comprises
78% of atmospheric volume
sodium nitrate,
Chile saltpetre
potassium nitrate
Indian salt petre
Phosphorous occurs in
Ca9(PO4)6. CaX2
(X = F, Cl or OH)
arsenic, antimony, and bismuth are mainly found in
sulfide ores
trend in radius in the 15th group
A considerable increase from N to P. only a small increase from As to Bi
the trend in IE in the 15th group
decreases down the group
trend in EN in the 15th group
Decreases down the group. but for heavier elements, the difference is not that prominent
Boiling point?in 15th group
increases down the group
melting point in the 15th group?
increases till As then decreases to Bi
Bismuth hardly forms elements in which OS
-3
The only well-characterized Bi (V) compound is
BiF5
Oxidation states of Nitrogen that disproportionate in acid medium
+1 to +4
phosphorous OS that disproportionate in both acidic and alkaline medium
+5 to -3
anomalous property of N is due to
small size, high electronegativity, high ionization enthalpy, and non-availability of orbitals
why the heavier elements cannot form p pi p pi bonding
their atomic orbitals are so
large and diffuse that they cannot have effective overlapping
why is a single N–N bond weaker than a single P–P bond
because of the high interelectronic repulsion of the non-bonding electrons, owing to the small bond length
order of stability of hydrides of group 15
The stability of hydrides decreases from NH3 to BiH3
reducing character of hydrides of group 15
increases
why does ammonia have higher MP and BP?
because it forms hydrogen bonding