One mole of which of the following has the highest entropy ?
Liquid nitrogen
Hydrogen gas
Mercury
Diamond
1 mole of H2SO4 is mixed with 2 moles of NaOH .The heat evolved will be :
57.3 kJ
2 x 57.3 kJ
57.3/2 kJ
Cannot be predicted
One mole. of a perfect gas expands isothermally to ten times of its original volume. The change in entropy is :
0.1 R
2.303 R
10.0 R
100.0 R
100 cc of 0.6 N H2SO4 and 200 cc of 0.3 N HCl were mixed together .The normality of the solution will be :
0.2 N
0.4 N
0.8 N
0.6 N
If the mass defect of is 0.090 u , then binding energy per nucleon is :
(1 u = 931.5 MeV)
9.315 MeV
931.5 MeV
83.0 MeV
8.38 MeV
50 mL of 0.1 M HCl and 50 mL of 0.2 M NaOH are mixed .The pH of the resulting solution is :
1.30
4.2
12.70
11.70
C.
12.70
50 mL of0.1 M HCl = = 5 x 10-3
50 mL of 0.2 M NaOH = = 10 x 10-3
Hence , after neutralisation NaOH left
= 10 x 10-3 - 5 x 10-3 = 5 x 10-3
Total volume = 100 cc
The concentration of NaOH
= = 0.05 M
[OH-] = 0.05 M = 5 x 10-2 M
pOH = - log [OH-]
= - log [5 x 10-2]
= 1.3010
pH + pOH = 14
pH = 14 - 1.3010
= 12.699
= 12.70
27Co60 is radioactive because :
its atomic number is high
it has high ratio
it has high ratio
None of the above