The vapor pressure of $......$ is maximum.

Which one of the following methyl diboranes does not exist?

Which of the following is radioactive?

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A:$ Hydrogen is an environment-friendly fuel.
Reason $R:$ Atomic number of hydrogen is $1$ and it is a very light element.
In the light of the above statements,choose the correct answer from the options given below:

In the water-gas shift reaction,hydrogen gas is produced from the reaction of steam with

Which of the following fuels has the maximum calorific value per gram?