1
AIPMT 2003
MCQ (Single Correct Answer)
+4
-1
Which one of the following statements is not correct for sigma- and pi- bonds formed between two carbon atoms?
A
sigma-bond is stronger than a pi-bond.
B
Bond energies of sigma- and pi-bonds are of the order of 264 kJ/mol and 347 kJ/mol, respectively
C
Free rotation of atoms about a sigma-bond is allowed but not in case of a pi-bond.
D
Sigma-bond determines the direction between carbon atoms but a pi-bond has no primary effect in this regard.
2
AIPMT 2003
MCQ (Single Correct Answer)
+4
-1
For the reaction,
C3H8(g) + 5O2(g) $$ \to $$ 3CO2(g) + 4H2O(l)
at constant temperature, $$\Delta $$H $$-$$ $$\Delta $$E is
A
+ RT
B
$$-$$3RT
C
+ 3RT
D
$$-$$ RT
3
AIPMT 2003
MCQ (Single Correct Answer)
+4
-1
For which one of the following equations is $$\Delta $$Horeact equal to $$\Delta $$Hof for the product ?
A
Xe(g) + 2F2(g) $$ \to $$ XeF4(g)
B
2CO(g) + O2(g) $$ \to $$ 2CO2(g)
C
N2(g) + O3(g) $$ \to $$ N2O3(g)
D
CH4(g) + 2Cl2(g) $$ \to $$ CH2Cl2(l) + 2HCl(g)
4
AIPMT 2003
MCQ (Single Correct Answer)
+4
-1
Formation of solution from two components can be considered as
(i) Pure solvent $$ \to $$ separated solvent molecules, $$\Delta $$H1
(ii) Pure solute $$ \to $$ separated solute molecules, $$\Delta $$H2
(iii) Separated solvent and solute molecules $$ \to $$ solution, $$\Delta $$H3
Solution so formed will be ideal if
A
$$\Delta $$Hsoln = $$\Delta $$H1 + $$\Delta $$H2 + $$\Delta $$H3
B
$$\Delta $$Hsoln = $$\Delta $$H1 + $$\Delta $$H2 $$-$$ $$\Delta $$H3
C
$$\Delta $$Hsoln = $$\Delta $$H1 $$-$$ $$\Delta $$H2 $$-$$ $$\Delta $$H3
D
$$\Delta $$Hsoln = $$\Delta $$H3 $$-$$ $$\Delta $$H1 $$-$$ $$\Delta $$H2