A exists as diatomic gas in nature
which is relatively inert and forms78% of earth's atmosphere.
(a) Identify
the gas and write its molecular formula. Write the formulae of its nitrite and
nitrate ions.
(b) How many
moles of this gas would contain12.044 x 1023 atoms of this element?
(Avogadro's
no. = 6.022 x 1023)
(c)
Calculate the molecular mass of
(a)
and (b)
(Given
atomic masses N == 14 u, 0 = 16 u,
H=1u)
(a) Define
Avogadro's number.
(b)Show that
100 g of water and 100 g of carbon dioxide are not equal in number of moles.
Molecular masses of water and carbon dioxide are 18 u and 44 u respectively.
(c) Calculate the
number of molecules present in the 100 g for both water and carbon dioxide.
Answer:
(a)
Nitrogen gas 
Nitrite ion 
, Nitrate ion 
(b) 1 mole
of 
gas = 6.022x1023
molecules of = 12.044 x1023
atoms of N
(c) (i)
Molecular mass of
= 14 + 1 x 4
+ 14 + 3 x 16 = 80 u
Molecular mass of 
=1+ 14 + 3 x16 = 63 u
You need to login to perform this action.
You will be redirected in
3 sec
