Chemistry NCERT Exemplar Solutions Class 12th Chapter Thirteen

For the reaction

H₂F₂(g) ® H₂(g) + F₂(g)

$\Delta U=-59.6kJmo{l}^{-1}at27°C$

The enthalpy change for the above reaction is ()__________kJ mol^-1. [nearest integer]

Consider an imaginary ion  The nucleus contains 'a'% more neutrons that the number f electrons in the ion. The value of 'a' is____________. [nearest integer]

A 10g mixture of hydrogen and helium is contained in a vessel of capacity 0.0125 m³ at 6 bar ansd $27°$ C. The mass of helium in the mixture is__________g. (nearest integer)

Given below are two statements : one is labeled as Assertion A and the other is labeled as Reason R.

Assertion A: Phenolphthalein is pH dependent indicator, remains colourless in acidic solution and gives pink colour in basic medium.

Reason R: Phenolphthalein is a weak acid. It doesn't dissociate in basic medium.

In the light of the above statements, choose the most appropriate answer from the options given below.

Consider the reaction and predict the major product.

The correct sequential order fo the reagents for the given reaction is

Which of the following is not an example of benzenoid compound?

Identify A in the following chemical reaction.

When neopentyl alcohol is heated with an acid, it slowly converted into an 85:15 mixture of alkenes $\mathrm{A}$ and $\mathrm{B}$ , respectively. What are these alkenes?

Identify the major product formed in the following sequence of reactions: