The vapour pressure of pure water is 25.0 mm Hg and that of an aqueous dilute solution of urea in 20mm Hg at 25°C. The molarity of the solution is:
12.6
14.9
13.8
9.6
The entropy will be positive in which of the following reaction change.
H2(g) + I2 (g) 2HI (g)
HCl(g) + NH3 (g) N2O(g) + 2H2O(g)
NH4NO3(s)N2O(g) + 2H2O(g)
MgO(s) + H2(g) Mg(s) + H2O(l)
Wave number of a spectral line for a given transition is xcm-1 for He+ then its value for Be+ (iso electronic of H+) for same transition is:
x cm-1
4x cm-1
cm-1
2x cm-1
The hybridisation and shape of IF5 are respectively:
sp3d , trigonal bipyramide
sp3d , see saw
sp3d , square pyramidal
sp3d , pentagonal pyramidal
On adding A to the reaction at equilibrium, AB (s) A(g) + B(g) the new equilibrium concentration of A becomes double, the equilibrium concentration of B would become:
1/2 of its original value
1/4 of its original value
1/8 of its original value
Twice its original value
Assuming that Hund's rule in violated,the bond order and magnetic nature of the diatomic molecule B2 is:
1 and diamagnetic
0 and diamagnetic
1 and paramagnetic
O and paramagnetic
A solution contains 10 mL of 0.1 N NaOH and 10mL of 0.05 NH2SO4.pH of this solution is:
zero
less than 7
greater than 7
7
C.
greater than 7
Number of milliequivalents of NaOH = 0.1 x 10 = 1
Number of milliequivalents of H2SO4
= 10 x 0.05 = 0.5
Milliequivalent of H2SO4 will neutralise NaOH so that (1-0.5) = 0.5 milliequivalent of NaOH is left unneutralised.
Therefore, pH of the resulting solution will be greater than seven i.e., pH > 7,
A cylinder of compressed gas contains nitrogen and oxygen in the ratio of 3:1 by mole. The total mass of the gas mixture if the cylinder is known to contain 2.5 x 104 g of oxygen will be:
8 x 103 g
9 x 104 g
9 x 103 g
8 x 102 g