Which of the following gives correct arrangement of compounds involved based on their bond strength ?
HF > HCl > HBr > HI
HI > HBr > HCl > HF
HF > HBr > HCl > HI
HCl > HF > HBr > HI
The enthalpy of combustion at 25°C of H2, cyclohexane (C6H12) and cyclohexene (C6H10) are -241, -3920 and -3800 kJ/mol respectively. The heat of hydrogenation of cyclohexene is :
-121 kJ/mol
+121 kJ/mol
-242 kJ/mol
+242 kJ/mol
The entropy values (in JK-1mol-1) of H2 (g) = 130.6, Cl2 (g) = 223.0 and HCl (g) = 186. 7 at 298 K and 1 atm pressure. Then entropy change for the reaction :
H2 ( g)+ Cl2 (g) 2HCl (g) is:
+540.3
+727.3
-166.9
+19.8
A certain sample of gas has a volume of 0.2 L measured at 1 a:tm pressure and 0°C. At the same pressure but 273°C, its volume will be :
0.4 L
0.8 L
27.8 L
55.6 L
Total number of atoms represented by the compound CuSO4 · 5H2O is :
27
21
5
8
B.
21
Total number of atoms present in compound CuSO4 . 5H2O is 21.
1 atom of Copper (Cu) + 1 atom of Sulphur (S) + 4 atom of Oxygen (O) + 10 atoms of Hydrogen (H) + 5 atoms of Oxygen (O)
= 1 + 1 + 4 + 10 + 5
= 21 atoms.
When electrons are trapped into the crystal in anion vacancy, the defect is known as :
Schottky defect
Frenkel defect
stoichiometric defect
F-centres
By which one of the following compounds both CH4 and CH3 - CH3 can be prepared in one step?
CH3I
CH3OH
CH3CH2I
C2H5OH
R - NH - COH Product
In the given reaction, what will be the product?
R - N = C = O
R - C-
R - C N
None of these