Choose the reaction in which H is not equal to U
C(graphite) + O2(g) → CO2(g)
C2H4(g) + H2(g) → C2H6(g)
2C(graphite) + H2(g) → C2H2(g)
H2(g) + I2(g) → 2HI(g)
The standard enthalpies of combustion of C6H6 (l), C(graphite) and H2 (g) are respectively -3270 kJ mol-1, -394 kJ mol-1 and -286 kJ mol-1. What is the standard enthalpy of formation of C6H6 (l) in kJ mol-1?
-48
+48
-480
+480
In the reaction; A2(g) + 3B2(g) → 2AB3(g), the standard entropies in (JK-1 mol-1) of A2(g), B2(g) and AB3(g) are respectively 190, 130 and 195 and the standard enthalpy change for the reaction is -95 kJ mol-1. The temperature (in K) at which the reaction attains equilibrium is (assuming both the standard entropy change and standard enthalpy change for this reaction are constant over a wide range of temperature)
500
400
300
200
In the following equilibrium reaction,
2A B + C
the equilibrium concentration of A, B and C are 1 × 10-3 M, 2 × 10-3 M and 3 × 10-3 M respectively at 300 K. The value of Kc for this equilibrium at the same temperature is
6
36
Which one of the following is the correct statement?
HCO is the conjugate base of CO
NH is the conjugate acid of NH3
H2SO4 is the conjugate acid of HSO
NH3 is the conjugate base of NH
0.02 mole of [Co(NH3)5Br]Cl2 and 0.02 mole of [Co(NH3)5Cl]SO4 are present in 200 cc of a solution X. The number of moles of the precipitates Y and Z that are formed when the solution X is treated with excess barium chloride are respectively.
0.02, 0.02
0.01, 0.02
0.02, 0.04
0.04, 0.02
The number of sigma (σ) and pi () bonds present in 1, 3, 5, 7-octatetraene respectively are
14 and 3
17 and 4
16 and 5
15 and 4
The molecule that contains only sp2 hybrid carbon atoms is
isoprene
acrylonitrile
but-1-ene
1,3-butadiene
D.
1,3-butadiene
The molecule that contains only sp2 hybrid carbon atom is 1, 3-butadiene.