A buffer solution is obtained by mixing 10 mL of 1.0M CH₃COOH and 20mL of 0.5M CH₃COONa and it is diluted to 100mL using distilled water. pK_a of CH₃COOH is 4.76. The pH of this buffer solution is 

• 2.76

• 3.76

• 4.76

• 0.76

12.

To which of the following determinations of heat, Hess's law is used?

• Heat of chemical reaction

• Heat of formation

• Heat of bond formation

• All of the above

1.0 L of 1.0 M solution of sodium hydroxide is neutralised by 1.0 L of 1.0 M of methanoic acid. If the heat of formation of water is X, the neutralisation energy of above reaction is

• less than X

• more than X

• equal to X

• None of the above

Which of the following units of energy, represents maximum amount of energy?

• Calorie

• Joule

• Erg

• Electron volt

Combustion of liquid benzene in oxygen occurs as 2C₆H₆ + 15O₂ → 12CO₂ + 6H₂O. At STP, what volume (in litre) of oxygen is required for the full combustion of 3.9 g liquid benzene?

• 11.2 L

• 22.4 L

• 8.4 L

• 7.4 L

Which one of the following is maximum electronegative?

• lead

• Silicon

• Carbon

• Tin

The reduction potential of three metallic ions X, Y and Z correspondingly are +0.52,-303 and -1.18 V. The sequence of reducing capacity of these metals will be

• Y >Z >X

• X >Y >Z

• X >Z >Y

• Z >X >Y

For the reaction ${\mathrm{MnO}}_4^{-} + {\mathrm{C}}_2{\mathrm{O}}_4^{2-} + {\mathrm{H}}^{+} \to {\mathrm{Mn}}^{2+} + {\mathrm{CO}}_2 + {\mathrm{H}}_2\mathrm{O}$.  Which of the following is correct?

• Mn2+	${\mathrm{C}}_2{\mathrm{O}}_4^{2-}$	CO2	H+
  5	2	4	10

• Mn+	${\mathrm{C}}_2{\mathrm{O}}_4^{2-}$	CO2	H+
  2	5	10	16

• Mn2+	C2O${}_4^{2-}$	CO2	H+
  6	8	16	18

• Mn2+	C2O${}_4^{2-}$	CO2	H+
  10	12	24	12

Acidic K₂Cr₂O₇ reacting with H₂S₂ the oxidation number of chromium is changed

• from +3 to +6

• from+6 to +3

• from +6 to +2

• remains unchanged

Which of the following compounds does not show optical isomerism?

• CH₃CH(OH)Br

• CH₃CH(OH)CH₃

• ${\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{CHBrCH}{<}_{{\mathrm{CH}}_3}^{{\mathrm{CH}}_3}$

• CH₃-CHOH-CHBr-CH₂OH