The correct sequence of steps during the corrosion of iron is
(A) Ferrous ions are oxidized by atmospheric oxygen
(B) Hydrated ferric oxide (\(\text{Fe}_2\text{O}_3 \cdot \text{H}_2\text{O}\)) formed with production of \(\text{H}^{+}\) ions
(C) At a particular spot of iron object, oxidation takes place and that spot behaves as anode
(D) Electron released at anode moves through metal and reduces oxygen in the presence of \(\text{H}^{+}\)
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There are mainly four series of the transition metals, \(3 d\) series ( \(S c\) to Zn), 4d series (Y to Cd), \(5 d\) series ( La and Hf to Hg ) and 6 d series which has \(A c\) and elements from \(R f\) to \(C n\). The two series of the inner transition metals; \(4 f\) (Ce to Lu) and \(5 f\) (Th to Lr) are known as lanthanoids and actinoids respectively. Their chemical properties are transitional between those of \(s\) and \(p\)-block elements. The transition metals (with the exception of Zn, Cd and Hg) are very hard and have low volatility. Their melting and boiling points are high. Transition metals have incomplete d subshell either in neutral atom or in their ions. With partly filled d orbitals these elements exhibit certain characteristic properties such as display of a variety of oxidation states, formation of coloured ions and entering into complex formation with a variety of ligands. The transition metals and their compounds are known for their catalytic activity.
Which of the following is not regarded as transition metal?

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Adsorption is a surface phenomenon which can be expressed by means of an empirical relationship know as Freundlich Adsorption isotherm. The relationship given by \(\frac{x}{m} = Kp^{\frac{1}{n}}\ (n > 1)\)
x = Mass of the gas adsorbed
m = Mass of adsorbent
p = Pressure at which adsorption takes place
K and n are constant
The curve of above relationship indicate that at a fixed pressure there is a decrease in physical adsorption with increase in temperature. At high pressure, curves become parallel to pressure axis, indicating saturation of the surface of adsorbent.
Adsorption of a gas follow Freundlich isotherm shown below. \(\frac{x}{m}\) is proportional to

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Ethers with the general formula \(C _n H _{2 n+2} O\) and functional group C-O-C may be divided as symmetrical and unsymmetrical.
Lower symmetrical ether may be obtained by the dehydration of alcohols at low temperatures in the presence of protic acids,
such as \(H _2 SO _4\) and \(H _3 PO _4\) whereas at high temperature intramolecular dehydration takes place.
Formation of ether from primary alcohols is also accompanied by the formation of small amount of alkenes.
Due to the steric hinderance, secondary and tertiary alcohols undergo elimination reaction rather than substitution reaction yielding alkene as major product. Ethers can also be obtained by heating alkyl halides with sodium or potassium alkoxides.
Substituted Ethers (secondary & tertiary) can also be prepared using this method.
If primary halides are replaced with secondary and tertiary halides, alkenes are the major products.
The major product in the following reaction is \(ROH + HOR \xrightarrow{ H _2 SO _4, 140^{\circ} C }\)

Collision frequency is :

Lactose on hydrolysis gives :

Which of the following complexes will show absorbance of light at the lowest wavelength?

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Broadly, genetic disorders may be grouped into two categories - Mendelian disorders and Chromosomal disorders. Mendelian disorders are mainly determined by alteration or mutation in the single gene. These disorders are transmitted to the offspring on the same lines as we have studied in the principle of inheritance. The trait may also be linked to the sex chromosome as in case of haemophilia. It is evident that this X-linked recessive trait shows transmission from carrier female of male progeny.
Match List I with List II

List I	List ll
(A) Autosomal dominant trait	(I) Klinefelter's Syndrome
(B) Autosomal recessive trait	(II) Sickle Cell Anaemia
(C) Sex linked recessive trait	(III) Myotonic Dystrophy
(D) Gain of chromosomes	(IV) Haemophilia

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If \(\theta\) is the angle between any two vectors \(\vec{a}\) and \(\vec{b}\), then \(|\vec{a} \cdot \vec{b}|=|\vec{a} \times \vec{b}|\) for \(\theta\) equal to __________.

If light of wavelength 412.5 nm is incident on each of the metals given below, which ones will show photoelectric emission ?

Metal	Work Function (eV)
Na	1.92
K	2.15
Ca	3.20
Mo	4.17

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The basicity of \(\text{H}_3\text{PO}_4\) is :

Adsorption is surface phenomenon and it differs from absorption which occurs throughout the body of the substance which absorbs. In physisorption the attractive forces are mainly van der Waal forces while in chemisorption actual bonding occurs between the particles of adsorbent and adsorbed more easily on the surface of a solid as compared to the gases which are liquified with difficulty. Adsorption increases with the increases in pressure and decreases as temperature is increased.According to adsorption theory of catalysis, the speed of the reaction increases because

A concave mirror has radius of curvature 2 m. Light from a distance star is incident on the mirror. The distance of the image of the star from the mirror is :