Aldehydes, Ketones and Carboxylic Acids — Chemistry STD 12 Science — Question

The experimental data for decomposition of N₂O₅
[2N₂O₅ → 4NO₂ + O₂]
in gas phase at 318K are given below:

t/s	0	400	800	1200	1600	2000	2400	2800	3200
102 × [N2O5]/mol L-1	1.63	1.36	1.14	0.93	0.78	0.64	0.53	0.43	0.35

1. Plot [N₂O₅] against t.
2. Find the half-life period for the reaction.
3. Draw a graph between log[N₂O₅] and t.
4. What is the rate law?
5. Calculate the rate constant.
6. Calculate the half-life period from k and compare it with (ii).

Give reasons for the following:
On electrolysis in acidic solution amino acids migrate towards cathode, while in alkaline solution these migrate towards anode.

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

1. Painful condition known as bends.
2. Feeling of weakness and discomfort in breathing at high altitude.

The air is a mixture of a number of gases. The major components are oxygen and nitrogen with approximate proportion of 20% is to 79% by volume at 298 K. The water is in equilibrium with air at a pressure of 10 atm. At 298 K if the Henry’s law constants for oxygen and nitrogen at 298 K are 3.30 × 10⁷ mm and 6.51 × 10⁷ mm respectively, calculate the composition of these gases in water.

On the basis of crystal theory, octahedral in the presence of strong field ligand and weak field ligand. Explain the difference in crystal field splitting.

Describe the physical and chemical properties of potassium permanganate.

The elements of 3d transition series are given as:
Sc Ti V Cr Mn Fe Co Ni Cu Zn.
Answer the following:

1. Write the element which shows maximum number of oxidation states. Give reason.
2. Which element has the highest m.p?
3. Which element shows only + 3 oxidation state?
4. Which element is a strong oxidizing agent in + 3 oxidation state and why?