Amines — Chemistry STD 12 Science — Question

Describe the dispersion methods for preparation of colloidal solution.

Match the items given in Column I and Column II.

	Column I		Column II
i.	Saturated solution	a.	Solution having same osmotic pressure at a given temperature as that of given solution.
ii.	Binary solution	b.	A solution whose osmotic pressure is less than that of another.
iii.	Isotonic solution	c.	Solution with two components.
iv.	Hypotonic solution	d.	A solution which contains maximum amount of solute that can be dissolved in a given amount of solvent at a given temperature.
v.	Solid solution	e.	A solution whose osmotic pressure is more than that of another.
vi	Hypertonic solution	f.	A solution in solid phase.

Write two applications of electrochemical series.

Comment on the statement that elements of the first transition series possess many properties different from those of heavier transition elements.

Match the compounds/elements given in Column I with uses given in Column II.

	Column I (Compound/element)		Column II (Use)
(i)	Lanthanoid oxide	(a)	Production of iron alloy
(ii)	Lanthanoid	(b)	Television screen
(iii)	Misch metal	(c)	Petroleum cracking
(iv)	Magnesium based alloy is constituent of	(d)	Lanthanoid metal + iron
(v)	Mixed oxides of lanthanoids are employed	(e)	Bullets
		(f)	In X-ray screen

 

1. Describe the general trends in the following properties of the first series of the transition elements:

1. Stability of +2 oxidation state.
2. Formation of oxometal ions.

2. Assign reason for each of the following:

1. Transition elements exhibit variable oxidation states.
2. Transition metal ions are usually coloured.

Using IUPAC norms write the formulas for the following:
a. Tetrahydroxozincate(II)
b. Potassium tetrachloridopalladate(II)
c. Diamminedichloridoplatinum(II)
d. Potassium tetracyanonickelate(II)
e. Pentaamminenitrito-O-cobalt(III)
f. Hexaamminecobalt (III) sulphate
g. Potassium tri(oxalato) chromate(III)
h. Hexaammineplatinum(IV)
i. Tetrabromidocuprate(II)
j. Pentaamminenitrito-N-cobalt(III)

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).