Science (English Medium) Class 12 - CBSE Important Questions for Chemistry

complete the following reaction: 

complete the following reaction: 

\[\begin{array}{cc}
\phantom{...}\ce{CH3} \\
| \\
\phantom{.................}\ce{CH3-CH-COOH ->[(i) Br2/Red P4][(ii)H2O]}
\end{array}\]

Write a chemical reaction to show that the open structure of D-glucose contains the following : 

 Aldehyde as a carbonyl group 

Give a reason for the following : 
N-N bond is weaker than the P-P bond.

Complete the following reaction:

Complete the following reaction:
\[\ce{(C6H5CH2)2Cd + 2CH3COCI}\]

An alkene ‘A’ (Mol. formula \[\ce{C5H10}\]) on ozonolysis gives a mixture of two compounds ‘B’ and ‘C’. Compound ‘B’ gives positive Fehling’s test and also forms iodoform on treatment with \[\ce{I2}\] and \[\ce{NaOH}\]. Compound ‘C’ does not give Fehling’s test but forms iodoform. Identify the compounds A, B and C. Write the reaction for ozonolysis and formation of iodoform from B and C.

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

Acetaldehyde, Acetone, Methyl tert butyl ketone (reactivity towards NH₂OH).

Give reasons to support the answer:

Presence of Alpha hydrogen in aldehydes and ketones is essential for aldol condensation.

Write the IUPAC name for the following organic compound:

Complete the following:

\[\ce{C6H5NO2 ->[Sn/HCl] A ->[Br2/H2O] B ->[NaNO2/HCl][273 - 278 K] C ->[HBF4][Δ] D}\]

Which of the following tests/reactions is given by aldehydes as well as ketones?

The oxidation of toluene to benzaldehyde by chromyl chloride is called ______.

Write the reaction and IUPAC name of the product formed when 2-Methylpropanal (isobutyraldehyde) is treated with ethyl magnesium bromide followed by hydrolysis.

Write the equations for the following reaction:

Salicylic acid is treated with acetic anhydride in the presence of conc H₂SO₄

A hydrocarbon (A) with molecular formula C₅H₁₀ on ozonolysis gives two products (B) and (C). Both (B) and (C) give a yellow precipitate when heated with iodine in presence of NaOH while only (B) give a silver mirror on reaction with Tollen’s reagent.

1. Identify (A), (B) and (C).
2. Write the reaction of B with Tollen’s reagent.
3. Write the equation for iodoform test for C.
4. Write down the equation for aldol condensation reaction of B and C.

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

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

Write the IUPAC name of the following complex:

K₂[PdCl₄]

Explain the following reactions:

Clemmensen reaction

Explain the following reactions:

Stephan reaction