A process is taking place at constant temperature and pressure. Then
ΔH = ΔE=0
ΔH= TΔS
ΔH= 0
ΔS= 0
In a mixture of acetic acid and sodium acetate the ratio of concentrations of the salt to the acid is increased ten times. Then the pH of the solution
increases by one
decreases by one
decreases ten fold
increases ten fold
The enthalpy of combustion of methane at 25°C is 890 kJ. The heat liberated when 3.2 g of methane burnt in air is
445 kJ
278 kJ
-890 kJ
178 kJ
The compounds A and B are mixed in equimolar proportion to form the products, A +B C+ D. At equilibrium, one third of A and B are consumed. The equilibrium constant for the reaction is
0.5
4.0
2.5
0.25
D.
0.25
In acetylene molecule, the two carbon atoms are linked by
one sigma-bond and two pi-bonds
two sigma-bonds and one pi-bond
three sigma-bonds
three pi-bonds
Pick out the alkane which differs from the other members of the group
2,2-dimethyl propane
pentane
2-methyl butane
2,2-dimethyl butane
In qualitative analysis, in order to detect second group basic radical, H2S gas is passed in the presence of dilute HCl to
increase the dissociation of H2S
decrease the dissociation of salt solution
decrease the dissociation of H2S
increase the dissociation of salt solution