Science (English Medium) Class 12 - CBSE Question Bank Solutions for Chemistry

Alcohols are comparatively more soluble in water than hydrocarbons of comparable molecular masses. Explain this fact.

Give reason for the higher boiling point of ethanol in comparison to methoxymethane.

Arrange the set of compounds in order of increasing boiling points.

Bromomethane, Bromoform, Chloromethane, Dibromomethane.

Arrange the set of compounds in order of increasing boiling points.

1-Chloropropane, Isopropyl chloride, 1-Chlorobutane.

Explain why alkyl halides, though polar, are immiscible with water?

p-Dichlorobenzene has higher m.p. and lower solubility than those of o- and m-isomers. Discuss.

Give simple chemical tests to distinguish between the following pairs of compounds :

Ethanol and phenol

Write one similarity and one difference between the chemistry of lanthanoid and actinoid elements.

What is the effect of adding a catalyst on Activation energy (E_a)

Arrange the following compounds in the increasing order of their acid strength:

p-cresol, p-nitrophenol, phenol

The cell in which the following reaction occurs:

`2Fe^(3+) (aq) + 2I^(-) (aq) ---> 2Fe^(2+) (aq) + I_2 (s)` has `E_"cell"^@` = 0.236 V at  298 K. Calculate the standard Gibbs energy of the cell reaction. (Given : 1 F = 96,500 C mol⁻¹)

A first-order reaction is 50% completed in 40 minutes at 300 K and in 20 minutes at 320 K. Calculate the activation energy of the reaction. (Given : log 2 = 0·3010, log 4 = 0·6021, R = 8·314 JK^–1 mol^–1)

Identify the chiral molecule in the following pair :

Write the structures of the main products of the following reactions:

Write the structures of the main products of the following reactions:

Write the structures of the main products of the following reactions:

How would you account the following :

Highest fluoride of Mn is MnF₄ whereas the highest oxide is Mn₂O₇.

Write the structures of A, B and C in the following reactions :

\[ C_6 H_5 {NO}_2 \to^{Sn/HCI} A \to^{{NaNO}_2 /HCI}_{273 K} B \to^{H_2 O}_∆ C\]

How do you prepare:

Actinoid elements show wide range of oxidation states.