Science (English Medium) कक्षा १२ - CBSE Question Bank Solutions for Chemistry

Explain the following phenomena with the help of Henry’s law.

Feeling of weakness and discomfort in breathing at high altitude.

Account for the following:

There are 5 OH groups in glucose

Account for the following:

What happens when D – glucose is treated with the following reagents

Bromine water

Account for the following:

What happens when D – glucose is treated with the following reagents

HNO₃

State Henry’s law and explain why are the tanks used by scuba divers filled with air diluted with helium (11.7% helium, 56.2% nitrogen and 32.1% oxygen)?

Assume that argon exerts a partial pressure of 6 bar. Calculate the solubility of argon gas in water. (Given Henry’s law constant for argon dissolved in water, K_H = 40 k bar)

Arrange the following in the increasing order of their property indicated:

Ethanal, Propanone, Propanal, Butanone (reactivity towards nucleophilic addition)

Observe the graph shown in figure and answer the following questions:

1. What is the order of the reaction?
2. What is the slope of the curve?
3. Write the relationship between k and t_1/2 (half life period).

What happens when propanone is treated with CH₃MgBr and then hydrolysed?

What happens when ethanal is treated with excess ethanol and acid?

Which will undergo faster nucleophilic addition reaction?

Acetaldehyde or Propanone

The slope in the plot of ln[R] vs. time for a first order reaction is ______.

Which of the following is most reactive in nucleophilic addition reactions?

Draw the geometrical isomers of [Co(en)₂Cl₂]²⁺. Which geometrical isomer of [Co(en)₂Cl₂]²⁺ is not optically active and why?

The following questions are case-based questions. Read the passage carefully and answer the questions that follow:

Answer the following:

(a) Write the name of the product when an aldehyde reacts with excess alcohol in the presence of dry HCl. (1)

(b) Why carboxylic acid is a stronger acid than phenol? (1)

(c) (i) Arrange the following compounds in increasing order of their reactivity towards CH₃MgBr: (1)

CH₃CHO, \[\begin{array}{cc}
\ce{(CH3)3C-C-CH3}\\
\phantom{....}||\\
\phantom{....}\ce{O}
\end{array}\],  \[\begin{array}{cc}
\ce{CH3-C-CH3}\\
||\\
\ce{O}
\end{array}\]

(ii) Write a chemical test to distinguish between propanal and propanone. (1)

OR

(c) Write the main product in the following: (2)

(i)
(ii)

Arrange the following in increasing order of their boiling point:

C₂H₅OH, C₂H₅NH₂, (C₂H₅)₃N

Aldehydes and ketones react with hydroxylamine to form ______.

The slope in the plot of `log  ["R"]_0/(["R"])` Vs. time for a first-order reaction is ______.

When D-glucose reacts with HI, it forms ______.

Solubility of gas in liquid decreases with increase in ______.