Identify compound 'B' in following series of reactions?

 Acetonitrile    $\underrightarrow{Na/alcohol}$  A  $\underrightarrow{NaNo_{2}/dil.HCl}$   B

A) Ethyl amine

B) Nitroethane

C) Ethyl alcohol

D) Ethyl chloride


 Which of the following actinoids exhibits only +3 oxidation state?

A) Lr (Z=103)

B) U (Z=92)

C) Th (Z=90)

D) Pa (Z=91)


 Which of the following reaction  of diazonium salt involves retention of diazonium group?

A) Reaction with phosphinic acid

B) Reaction with dilute sulphuric acid

C) Reaction with HCl and Cu powder

D) Reaction with phenol


 Which of the following is obtained by catalytic oxidation of ammonia?

A) $N_{2}O$


C) $HNO_{2}$

D) $NO_{2}$


An ideal gas expands isothermally  and reversibly from 10m3 to 20m3 at 300 K, performing 5.187 kj of work on surrounding, calculate the number of moles of gas used

A) 1.5

B) 1

C) 3

D) 2