Which of the following is paramagnetic?

$CO$ has the same number of electrons as which of the following ions? Or,which ion is isoelectronic with $CO$?

Give reasons for the following:
$A$. Covalent bonds are directional bonds while ionic bonds are non-directional.
$B$. Water molecule has bent structure whereas carbon dioxide molecule is linear.
$C$. Ethyne molecule is linear.

$P_4O_{10}$ has short and long $P-O$ bonds. The number of short $(P=O)$ bonds in this compound is:

Which of the following orders are correct against the property given?

$(I)$	Dipole moment	$NF_3 > NH_3 > BF_3$
$(II)$	Covalent bond length	$C-O > N-O > O-H$
$(III)$	Bond order	$C_2 > B_2 > He_2$

The number of $S-S$,$S-O-S$,and $O-H$ linkages in a molecule of pyrosulphurous acid $(H_2S_2O_5)$ are respectively