Read the passage given below and answer the following questions: Transition elements are elements that have partially filled d-orbitals. The configuration of these elements corresponds to (n - 1)d^ 1-10 ns^ 1-2 . It is important to note that the elements mercury, cadmium and zinc are not considered transition elements because of their electronic configurations, which corresponds to (n - 1)d^ 10 ns^2. Some general properties of transition elements are: These elements can fonn coloured compounds and ions due to d-d transition; These elements exhibit many oxidation states; A large variety of ligands can bind themselves to these elements, due to this, a wide variety of stable complexes formed by these ions. The boiling and melting point of these elements are high. These elements have a large ratio of charge to the radius. In these questions (Q. No. i-iv), a statement of assertion followed by a statement ofreason is given. Choose the correct answer out of the following choices. 1. Assertion: Tungsten has very high melting point. Reason: Tungsten is a covalent compound. 2. Assertion: Zn, Cd and Hg are normally not considered transition metals. Reason: d-Orbitals in Zn, Cd and Hg elements are completely filled, hence these metals do not show the general characteristics properties of the transition elements. 3. Assertion: Copper metal gets readily corroded in acidic aqueous solution such as HCl and dil. H_2SO_4. Reason: Free energy change for this process is positive. 4. Assertion: Tailing of mercury occurs on passing ozone through it. Reason: Due to oxidation of mercury. 5. Assertion: Transition metals are poor reducing agents. Reason: Transition metals fonn numerous alloys with other metals.

Read the passage given below and answer the following questions: …

Give the structures of A and B in the following reactions

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What change in the concentration of H₂ will triple the rate of reaction?
(c). Suppose a reaction between A and B, was experimentally found to be first order with respect to both A and B. So the rate equation is:
Rate = k[A][B]
Which of these two mechanisms is consistent with this experimental finding? Why?
Mechanism 1
A → C + D (slow)
B+C → E (fast)
Mechanism 2
A+B →C + D (slow)
C → E (fast)

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Read the passage given below and answer the following questions: If some solute is added to a solvent, the boiling point of solution increases. This is known as elevation in baiting point. $\Delta\text{T}_\text{b}=\text{K}_\text{b}\text{m}$ where$, K_b =$ Molal elevation constant, $\Delta\text{T}_\text{b}\propto\text{m}$ Hence, it is a colligative property, Also, $\text{K}_\text{b}=\frac{\text{MRT}^2_\text{b}}{\Delta\text{Vap}\text{H}\times1000}$ where$, M =$ Molar mass of solvent, $\Delta\text{vap} H =$ Enthalpy of vaporisation, Molar mass can also be calculated using elevation in boiling point. $\text{M}_\text{B}=\frac{\text{K}_\text{B}\times\text{W}_\text{B}\times1000}{\Delta\text{T}_\text{b}\times\text{W}_\text{A}}$
A statement of assertion followed by a statement of reason is given.
Choose the correct answer out of the following choices.

Assertion and reason both are correct statements and reason is correct explanation for assertion.
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
Assertion is correct statement but reason is wrong statement.
Assertion is wrong statement but reason is correct statement.

Assertion : In a pressure cooker, the water is brought to boil. The cooker is then removed from the stove. Now on removing the lid of pressure cooker, the water starts boiling again.

Reason : The impurities in water bring down its boiling point.

Assertion : On dissolving $3.24g$ of sulphur in $40g$ of benzene, boiling point of solution get higher than that of benzene by $0.081K,$ then the formula of sulphur is $S_8.\ (K_b$ for benzene $= 2.53K \ kg\ mol^{-1})$

Reason : Molecular mass of sulphur comes out to be $253.$

Assertion : When sugar is added to water, boiling point of water increases.

Reason: When a non$-$volatile solute is added to a solvent, elevation in boiling point is observed.

Assertion : Cooking time in pressure cookers is reduced.

Reason: Boiling point inside the pressure cooker in raised.

Assertion : Elevation in boiling point of two isotonic solutions is same.

Reason : Boiling point depends upon the concentration of the solute.

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Amines are basic in nature. The $pK_b$ value is a measure of the basic strength of an amine. Lower the value of $pK_b$ more basic is the amine. The effect of substituent on the basic strength of amines in aqueous solution was determined using titrations. The substituent $''X\ ''$ replaced $''-CH_2\ ''$ group in piperidine $($ compound $1)$ and propylamine $\ce{CH_3CH_2CH_2NH_2}, ($compound $2).$
Compound $1:$

Compound $2: \ce{HXCH_2CH_2NH_2}$

$($source: Hall $\text{Jr, H. K.} (1956).$ Field and inductive effects on the base strengths of amines. Journal of the American Chemical Society, $78(11), 2570-2572.)$
Study the above data and answer the following questions:
$a.$ Plot a graph between the electronegativity of the substituent vs $pK_b$ value of the corresponding substituted propyl amine $($given that $pK_a + pK_b =14).$ Is there any relation between the electronegativity of the substituent and its basic strength?
$b.$ The electronegativity of the substituent $''C_6H_5CON\ ''$ is $3.7,$ what is the expected $pKa$ value of compound $\ce{C_6H_5CONHCH_2CH_2NH_2}$?
$(i)\ 9.9\ (ii)\ 9.5\ (iii)\ 9.3\ (iv)\ 9.1$
$c.$ The pKa value of the substituted piperidine formed with substituent $''X\ ''$ is found to be $8.28.$ What is the expected electronegativity of $''X\ ''$
$(i)\ 3.5\ (ii)\ 3.4\ (iii)\ 3.8\ (iv)\ 3.1$

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Read the passage given below and answer the following questions:
Nucleophilic substitution reactions are of two types; substitution nucleophilic bimolecular $(S_N2)$ and substitution nucleophilic unimolecular $(S_N1)$ depending on molecules taking part in determining the rate of reaction. Reactivity of alkyl halide towards $S_N1$ and $S_N2$ reactions depends on various factors such as steric hindrance, stability of intermediate or transition state, and polarity of solvent. $S_N2$ reaction mechanism is favoured mostly by primary alkyl halide then secondary and then tertiary. This order is reversed in case of $S_N1$ reactions.
The following questions are multiple choice questions. Choose the most appropriate answer:

Which of the following is most reactive towards nucleophilic substitution reaction?

$\ce{C_6H_5Cl}$
$\ce{CH_2 = CHCl}$
$\ce{ClCH_2CH = CH_2}$
$\ce{CH_3CH = CHCl}$

Isopropyl chloride undergoes hydrolysis by:

$S_N1$ mechanism.
$S_N2$ mechanism.
$S_N1$ and $S_N2$ mechanism.
Neither $S_N1$ nor $S_N2$ mechanism.

The most reactive nucleophile among the following is:

$\ce{CH_3O^-}$
$\ce{C_6H_5O^-}$
$\ce{(CH_3)_2CHO^-}$
$\ce{(CH_3)_3CO^-}$

Tertiary alkyl halides are practically inert to substitution by $S_N2$ mechanism because of:

Insolubility.
Instability.
Inductive effect.
Stearic hindrance.

Which of the following is the correct order of decreasing $S_N2$ reactivity?

$\ce{RCH_2X > R_2CHX > R_3CX}$
$\ce{R_3CX > R_2CHX > RCH_2X}$
$\ce{R_2CHX > R_3CX > RCH_2X}$
$\ce{RCH_2X > R_3CX > R_2CHX}$

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Read the passage given below and answer the following questions: According to Raoult's law, the partial pressure of two components of the solution maybe given as: $\text{P}_\text{A}=\stackrel{{0}}{\hbox{PA }}\text{x}_\text{A}$ and $\text{P}_\text{B}=\stackrel{{0}}{\hbox{PB }}\text{x}_\text{B}$ For an ideal solution (obeys Raoult's law always) $\Delta\text{H}_\text{mix}=0,\Delta\text{mix}=0$ All solutions do not obey Raoults law over entire range of concentration. These are known as non-ideal solutions. For non-ideal solutions, $\text{P}_\text{A}\not=\stackrel{{0}}{\hbox{PA }}\text{x}_\text{A}$ or $\text{P}_\text{B}\not=\stackrel{{0}}{\hbox{PB }}\text{x}_\text{B}$ Positive deviation $\Rightarrow\text{P}_\text{A}>\stackrel{{0}}{\hbox{PA }}\text{x}_\text{A}$ and $\text{P}_\text{B}>\stackrel{{0}}{\hbox{PB }}\text{x}_\text{B}$ Negative deviation $\text{P}_\text{A}<\stackrel{{0}}{\hbox{PA }}\text{x}_\text{A}$ and $\text{P}_\text{B}\stackrel{{0}}{\hbox{PB }}\text{x}_\text{B}$ A statement of assertion followed by a statement ofreason is given. Choose the correct answer out of the following choices.

Assertion and reason both are correct statements and reason is correct explanation for assertion.
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
Assertion is correct statement but reason is wrong statement.
Assertion is wrong statement but reason is correct statement.

Assertion: An ideal solution obeys Raoult's law.

Reason: In an ideal solution, solute-solute as well as solvent-solvent interactions are similar to solute-solvent interactions.

Assertion: Acetone and aniline show negative deviations.

Reason: H-bonding between acetone and aniline is stronger than that between acetone-acetone and aniline-aniline.

Assertion: Azeotropic mixtures are formed only by non-ideal solutions and they may have boiling points either greater than both the components or lesser than both the components.

Reason: The composition of the vapour phase is same as that of the liquid phase of an azeotropic mixture.

Assertion: The solutions which show negative deviations from Raoult's law are called maximum boiling azeotropes.

Reason: 68% nitric acid and 32% water by mass fonn maximum boiling azeotrope.

Assertion: $\Delta\text{H}_{\text{mix}}$ mix and $\Delta\text{V}_{\text{mix}}$ are positive for an ideal solution.

Reason: The interactions between the particles of the components of an ideal solution are almost identical as between particles in the liquids.

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Describe detailed information on classification of carbohydrates.

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For the reaction : $2\text{NO}_\text{(g)}+\text{Cl}_{2\text{(g)}}\rightarrow2\text{NOCl}_\text{(g)},$ the following data were collected. All the measurements were taken at $263K.$

Experiment No.	Initial $\ce{[NO] (M)}$	Initial $\ce{[Cl_2] (M)}$	Initial rate of disapp. of $\ce{Cl_2 (M/ min)}$
$1.$	$0.15$	$0.15$	$0.60$
$2.$	$0.15$	$0.30$	$1.20$
$3.$	$0.30$	$0.15$	$2.40$
$4.$	$0.25$	$0.25$	$?$

The following questions are multiple choice questions. Choose the most appropriate answer:

The molecularity of the reaction is:

$1$
$2$
$3$
$4$

The expression for rate law is:

$\text{r}=\text{k}[\text{NO}][\text{Cl}_2]$
$\text{r}=\text{k}[\text{NO}]^2[\text{Cl}_2]$
$\text{r}=\text{k}[\text{NO}][\text{Cl}_2]^2$
$\text{r}=\text{k}[\text{NO}]^2[\text{Cl}_2]^2$

The overall order of the reaction is:

$2$
$0$
$1$
$3$

The value of rate constant is:

$150.32\ M^{-2}\ min^{-1}$
$200.08\ M^{-1}\ min^{-1}$
$177.77\ M^{-2}\ min^{-1}$
$155.75\ M^{-1}\ min^{-1}$

The initial rate of disappearance of $Cl_2$ in experiment $4$ is:

$1.75\ M\ min^{-1}$
$3.23\ M\ min^{-1}$
$2.25\ M\ min^{-1}$
$2.77\ M\ min^{-1}$

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Read the passage given below and answer the following questions :
The transition elements have incompletely filled $d-$subshells in their ground state or in any of their oxidation states. The transition elements occupy position in betweens- and $p-$blocks in groups $3-12$ of the Periodic table. Starting from fourth period, transition elements consists of four complete series : $Sc$ to $Zn, Y$ to $Cd$ and $La, Hf$ to $Hg$ and $Ac, Rf$ to $Cn$. In general, the electronic configuration of outer orbitals of these elements is $(n - 1)d^{1-10} n^{1-2}$. The electronic configurations of outer orbitals of $Zn, Cd, Hg$ and $Cn$ are represented by the general formula $(n - 1)d^{10}ns^2$. All the transition elements have typical metallic properties such as high tensile strength, ductility, malleability. Except mercury, which is liquid at room temperature, other transition elements have typical metallic structures. The transition metals and their compounds also exhibit catalytic property and paramagnetic behaviour. Transition metal also forms alloys. An alloy is a blend of metals prepared by mixing the components. Alloys may be homogeneous solid solutions in which the atoms of one metal are distributed randomly among the atoms of the other.
The following questions are multiple choice questions. Choose the most appropriate answer:

Which of the following characteristics of transition metals is associated with higher catalytic activity?

High enthalpy of atomisation.
Variable oxidation states.
Paramagnetic behaviour.
Colour of hydrated ions.

Transition elements form alloys easily because they have.

Same atomic number.
Same electronic configuration.
Nearly same atomic size.
Same oxidation states.

The electronic configuration of tantalum $(Ta)$ is:

$[Xe]4f^05d^16s^2$
$[Xe]4f^{14}5d^26s^2$
$[Xe]4f^{14}5d^36s^2$
$[Xe]4f^{14}5d^46s^2$

Which one of the following outer orbital configurations may exhibit the largest number of oxidation states?

$3d^54s^1$
$3d^54s^2$
$3d^24s^2$
$3d^34s^2$

The correct statement$(s)$ among the following is/ are :

All $d$ and $f-$block elements are metals.
All $d$ and $f-$block elements form coloured ions.
All $d$ and $f-$block elements are paramagnetic.

$(I)$ only
$(I)$ and $(II)$ only
$(II)$ and $(III)$ only
$(I), (II)$ and $(III)$

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Read the passage given below and answer the following questions: The phenomenon of the flow of solvent through a semipermeable membrane from pure solvent to the solution is called osmosis. Sometimes a pressure is applied to stop the process of osmosis, this is known as osmotic pressure. It is denoted by $\pi.$ Osmotic pressure is expressed as : $\pi=\text{CRT}$ Since, osmotic pressure depends upon the molar concentration of solution, therefore it is a colligative property. A statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.

Assertion and reason both are correct statements and reason is correct explanation for assertion.
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
Assertion is correct statement but reason is wrong statement.
Assertion is wrong statement but reason is correct statement.

Assertion: If red blood cells were removed from the body and placed in pure water, pressure inside the cells increases.

Reason: The concentration of salt content in the cells increases.

Assertion: The osmotic pressure of a solution obtained by mixing 100mL of 3.4% solution of urea and 100mL of 1.6% solution of cane sugar at 293K is 7.46 bar.

Reason: The total osmotic pressure will be equal to the sum of partial osmotic pressures.

Assertion: When a solution is separated from the pure solvent by a semipermeable membrane, the solvent molecules pass through it from pure solvent side to the solution side.

Reason: Diffusion of solvent occurs from a region of high concentration to a region of low concentration solution.

Assertion: Two solutions having same osmotic pressure at a given temperature are called isotonic solutions.

Reason: Osmotic pressure is not a colligative property.

Assertion: The preservation of meat by salting and fruits by adding sugar protects against bacterial action.

Reason: A bacterium on salted meat or candid fruit loses water due to osmosis shrivels and ultimately dies.

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