MHT CET 2016 :: Chemistry :: General questions

• Chemistry - General questions

The reagent used in Wolff-Kishner reduction is 

Answer:

Explanation:

 The reagent used in the Wolff-\kishner reduction is $NH_{2}$-$NH_{2}$ and KOH in ethylene glycol. This reaction is the specific method for the reduction of 

The criterion  for a spontaneous process is

Answer:

Explanation:

The criterion for a spontaneous process is $\triangle $ G <0.

 Gibbs free energy is the maximum amount of energy available to a system  during a process, that can be converted in to useful work

 $\triangle G= \triangle H- T\triangle S$

 It is called the Gibbs-Helmholtz equation and useful in predicting  the spontaneity of the process

if $\triangle G$ = -ve , the process is spontaneous

if $\triangle $ G=+ve, the process is a non-spontaneous process

 If $\triangle$ G= zero , the process is in equilibrium

The molecular formula of Wilkinson’s  catalyst  used in the hydrogenation of alkenes is

Answer:

Explanation:

The molecular formula of Wilkinson's catalyst is $(Ph_{3}P)_{3}$ RhCl  that is used in hydrogenation of alkenes. Its IUPAC name is  chlorotris (triphenyl phosphine )

rhodium(l). This compound  is square planar in nature

What is the combining ratio of glycerol and fatty acid when they combine to form triglyceride?

Answer:

Explanation:

One molecule of glycerol and three molecules of fatty acids combine to form a triglyceride.

The rate constant and half-life of a first order reaction are related to each other as

Answer:

Explanation:

For first order reaction,    $k=\frac{2.303}{t}\log\frac{[A_{0}]}{[A]}$

At   $t= t_{1/2}$,[A]=$[A_{0}]$/2

$k=\frac{2.303}{t_{1/2}}\log\frac{[A_{}]}{[A_{0}]/2};k=\frac{2.303}{t_{1/2}}\log 2$

$k=\frac{2.303}{t_{1/2}} $    or $t_{1/2}=\frac{0.693}{k}$

• Chemistry - General questions