NCERT

Temperature dependence of resistivity ρ(T) of semiconductors, insulators, and metals is significantly based on the following factors:
a) number of charge carriers can change with temperature T
b) time interval between two successive collisions can depend on T
c) length of material can be a function of T
d) mass of carriers is a function of T

The correct answer is a) number of charge carriers can change with temperature T b) time interval between two successive collisions can depend on T

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$H _{3} PO _{3}$ can be represented by structures 1 and 2 shown below. Can these two structures be taken as the canonical forms of the resonance hybrid representing $H _{3} PO _{3}$ ? If not, give reasons for the same.

Solution: The positions of the atoms remain constant in canonical forms, but the positions of the electrons change. The positions of atoms change in the given canonical forms. As a result, they...

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From a class of 25 students, 10 are to be chosen for an excursion party. There are 3 students who decide that either all of them will join or none of them will join. In how many ways can the excursion party be chosen?

In this question we get $2$ options that is (i) Either all $3$ will go Then remaining students in class are: \[25\text{ }-\text{ }3\text{ }=\text{ }22\] Number of students remained to be chosen for...

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In an examination, a question paper consists of 12 questions divided into two parts i.e., Part I and Part II, containing 5 and 7 questions, respectively. A student is required to attempt 8 questions in all, selecting at least 3 from each part. In how many ways can a student select the questions?

The student can choose $3$ questions from $part\;I$ and $5$ from $part\;II$ Or $4\;questions$ from $part\;I$ and $4$ from $part \;II$ $5$ questions from $part\;I$ and $3$ from $part \;II$

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Find the vector equation of the line passing through $(1,2,3)$ and parallel to the planes $\overrightarrow{\mathrm{r}} \cdot(\hat{\mathrm{i}}-\hat{\mathrm{j}}+2 \hat{\mathrm{k}})=5$ and $\overrightarrow{\mathrm{r}} \cdot(3 \hat{\mathrm{i}}+\hat{\mathrm{j}}+\hat{\mathrm{k}})=6$

Solution: The vector eq. of a line passing through a point with position vector $\vec{a}$ and parallel to a vector $\vec{b}$ is $\vec{r}=\vec{a}+\lambda \vec{b}$ It is given that the line passes...

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Find the distance of the point $(-1,-5,-10)$ from the point of intersection of the line $\overrightarrow{\mathrm{r}}=(2 \hat{\mathrm{i}}-\hat{\mathrm{j}}+2 \hat{\mathrm{k}})+\lambda(3 \hat{\mathrm{i}}+4 \hat{\mathrm{j}}+2 \hat{\mathrm{k}})$ and the plane $\overrightarrow{\mathrm{r}} \cdot(\hat{\mathrm{i}}-\hat{\mathrm{j}}+\hat{\mathrm{k}})=5$

Solution: It is given that, The eq. of line is $\overrightarrow{\mathrm{r}}=(2 \hat{\mathrm{i}}-\hat{\mathrm{j}}+2 \hat{\mathrm{k}})+\lambda(3 \hat{\mathrm{i}}+4 \hat{\mathrm{j}}+2 \hat{\mathrm{k}})...

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Find the equation of the plane which contains the line of intersection of the planes $\vec{r} \cdot(\hat{1}+2 \hat{j}+3 \hat{k})-4=0$ and $\vec{r} \cdot(2 \hat{i}+\hat{j}-\hat{k})+5=0$ And which is perpendicular to the plane $\overrightarrow{\mathrm{r}} \cdot(5 \hat{\mathrm{i}}+3 \hat{\mathrm{j}}-6 \hat{\mathrm{k}})+8=0$

Solution: It is known that, The eq. of any plane through the line of intersection of the planes $\overrightarrow{\mathrm{r}} \cdot \overrightarrow{\mathrm{n}_{1}}=\mathrm{d}_{1}$ and...

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Find the equation of the plane passing through the line of intersection of the planes $\vec{r} \cdot(\hat{i}+\hat{j}+\hat{k})=1$ and $\vec{r} \cdot(2 \hat{i}+3 \hat{j}-\hat{k})+4=0$ and parallel to $x$-axis.

Solution: It is known to us that, The eq. of any plane through the line of intersection of the planes $\vec{r} \cdot \overrightarrow{n_{1}}=d_{1}$ and $\vec{r} \cdot \overrightarrow{n_{2}}=d_{2}$ is...

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Find the shortest distance between lines $\vec{r}=(6 \hat{i}+2 \hat{j}+2 \hat{k})+\lambda(1 \hat{i}-2 \hat{j}+\hat{2}) \text { and } \overrightarrow{1}=(-4 \hat{i}-\hat{k})+\mu(3 \hat{i}-2 \hat{j}-2 \hat{k})$

Solution: It is known to us that the shortest distance between lines with vector equations $\vec{r}=\overrightarrow{a_{1}}+\lambda \overrightarrow{b_{1}}$ and $\vec{r}=\overrightarrow{a_{2}}+\lambda...

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If $\mathrm{l}_{1}, \mathrm{~m}_{1}, \mathrm{n}_{1}$ and $\mathrm{l}_{2}, \mathrm{~m}_{2}, \mathrm{n}_{2}$ are the direction cosines of two mutually perpendicular lines, show that the direction cosines of the line perpendicular to both of these are $\left(\mathrm{m}_{1} \mathrm{n}_{2}-\mathrm{m}_{2} \mathrm{n}_{1}\right),\left(\mathrm{n}_{1} \mathrm{l}_{2}-\mathrm{n}_{2} \mathrm{l}_{1}\right),\left(\mathrm{l}_{1} \mathrm{~m}_{2}-\mathrm{l}_{2} \mathrm{~m}_{1}\right)$

Solution: Let's consider $l, m, n$ be the direction cosines of the line perpendicular to each of the given lines. Therefore, $ll_{1}+m m_{1}+n n_{1}=0 \ldots(1)$ And...

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In the following cases, determine whether the given planes are parallel or perpendicular, and in case they are neither, find the angles between them.
(a) 2x – 2y + 4z + 5 = 0 and 3x – 3y + 6z – 1 = 0
(b) 2x – 2y + 4z + 5 = 0 and 3x – 3y + 6z – 1 = 0

Solution: (a) $2 x-2 y+4 z+5=0$ and $3 x-3 y+6 z-1=0$ It is given that The eq. of the given planes are $2 x-2 y+4 z+5=0$ and $x-2 y+5=0$ It is known to us that, two planes are $\perp$ if the...

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In the following cases, determine whether the given planes are parallel or perpendicular, and in case they are neither, find the angles between them.
(a) 7x + 5y + 6z + 30 = 0 and 3x – y – 10z + 4 = 0
(b) 2x + y + 3z – 2 = 0 and x – 2y + 5 = 0

Solution: (a) $7 x+5 y+6 z+30=0$ and $3 x-y-10 z+4=0$ It is given that The eq. of the given planes are $7 x+5 y+6 z+30=0$ and $3 x-y-10 z+4=0$ Two planes are $\perp$ if the direction ratio of the...

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Find the vector and Cartesian equations of the planes
(a) that passes through the point $(1,0,-2)$ and the normal to the plane is $\hat{i}+\hat{j}-\hat{k}$
(b) that passes through the point $(1,4,6)$ and the normal vector to the plane is $\hat{i}-2 \hat{j}+\hat{k}$

Solution: (a) That passes through the point $(1,0,-2)$ and the normal to the plane is $\hat{\mathrm{i}}+\hat{\mathrm{j}}-\hat{\mathrm{k}}$ Let's say that the position vector of the point $(1,0,-2)$...

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Find the shortest distance between the lines whose vector equations are $\begin{array}{l} \vec{r}=(1-t) \hat{i}+(t-2) \hat{j}+(3-2 t) \hat{k} \text { and } \\ \vec{r}=(s+1) \hat{i}+(2 s-1) \hat{j}-(2 s+1) \hat{k} \end{array}$

Solution: Consider the given equations $\begin{array}{l} \Rightarrow \vec{r}=(1-t) \hat{i}+(t-2) \hat{j}+(3-2 t) \hat{k} \\ \vec{r}=\hat{i}-t \hat{i}+t \hat{j}-2 \hat{j}+3 \hat{k}-2 t \hat{k} \\...

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Find the shortest distance between the lines whose vector equations are $\vec{r}=(\hat{i}+2 \hat{j}+3 \hat{k})+\lambda(\hat{i}-3 \hat{j}+2 \hat{k})$ and $\vec{r}=4 \hat{i}+5 \hat{j}-6 \hat{k}+\mu(2 \hat{i}+3 \hat{j}+\hat{k})$

Solution: It is known to us that shortest distance between two lines $\vec{r}=\overrightarrow{a_{1}}+\lambda \overrightarrow{b_{1}}$ and $\vec{r}=\overrightarrow{a_{2}}+\mu \overrightarrow{b_{2}}$...

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Find the angle between the following pairs of lines:
(i) $\vec{r}=2 \hat{i}-5 \hat{j}+\hat{k}+\lambda(3 \hat{i}+2 \hat{j}+6 \hat{k})$ and $\overrightarrow{\mathrm{r}}=7 \hat{\mathrm{i}}-6 \hat{\mathrm{k}}+\mu(\hat{\mathrm{i}}+2 \hat{\mathrm{j}}+2 \hat{\mathrm{k}})$
(ii) $\vec{r}=3 \hat{i}+\hat{j}-2 \hat{k}+\lambda(\hat{i}-\hat{j}-2 \hat{k})$ and $\overrightarrow{\mathrm{r}}=2 \hat{\mathrm{i}}-\overrightarrow{\mathrm{j}}-56 \hat{\mathrm{k}}+\mu(3 \hat{\mathrm{i}}-5 \hat{\mathrm{j}}-4 \hat{\mathrm{k}})$

Solution: Let's consider $\theta$ be the angle between the given lines. If $\theta$ is the acute angle between $\vec{r}=\overrightarrow{a_{1}}+\lambda \overrightarrow{b_{1}}$ and...

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Find the equation of the line in vector and in Cartesian form that passes through the point with position vector $2 \hat{\mathrm{i}}-\hat{\mathrm{j}}+4 \hat{\mathrm{k}}$ and $\hat{\mathrm{i}}+2 \hat{\mathrm{j}}-\hat{\mathrm{k}}$. is in the direction

Solution: Given: Vector equation of a line that passes through a given point whose position vector is $\vec{a}$ and parallel to a given vector $\vec{b}$ is $\vec{r}=\vec{a}+\lambda \vec{b}$ Let,...

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Write balanced equations for: $(\mathbf{i}) \mathbf{B} \mathbf{F}_{3}+\mathrm{LiH} \rightarrow$ (ii) $\mathrm{B}_{2} \mathrm{H}_{6}+\mathrm{H}_{2} \mathrm{O} \rightarrow$ (iii) $\mathrm{NaH}+\mathrm{B}_{2} \mathrm{H}_{6} \rightarrow$ (iv) $\mathbf{H}_{3} \mathbf{B O}_{3} \rightarrow$ (v) $\mathrm{Al}+\mathrm{NaOH} \rightarrow$ (vi) $\mathrm{B}_{2} \mathrm{H}_{6}+\mathrm{NH}_{3} \rightarrow$

Solution: The balanced equations are as follow:    

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A certain salt $X$ gives the following results. (i) Its aqueous solution is alkaline to litmus. (ii) It swells up to a glassy material $\mathbf{Y}$ on strong heating. (iii) When conc. $\mathrm{H}_{2} \mathrm{SO}_{4}$ is added to a hot solution of $\mathrm{X}$, a white crystal of an acid $\mathrm{Z}$ separates out Write equations for all the above reactions and identify X, $Y$, and $Z$.

Solution: The salt given to litmus is antacid. $X$ is, subsequently, a salt with a solid base, and a feeble corrosive. When $X$ is warmed unnecessarily, it additionally enlarges to frame material...

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When metal $\mathrm{X}$ is treated with sodium hydroxide, a white precipitate (A) is obtained, which is soluble in excess of $\mathrm{NaOH}$ to give soluble complex (B). Compound (A) is soluble in dilute HCI to form compound (C). The compound (A) when heated strongly gives (D), which is used to extract the metal. Identify (X), (A), (B), (C) and (D). Write suitable equations to support their identities.

Solution: The given metal $X$ gives sodium hydroxide to a white accelerate, and the encourage breaks up surpassing sodium hydroxide. $X$ must, consequently, be made of aluminum. The acquired white...

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(a) Classify the following oxides as neutral, acidic, basic or amphoteric. $\mathrm{CO}, \mathrm{B}_{2} \mathrm{O}_{3}, \mathrm{SiO}_{2}, \mathrm{CO}_{2}, \mathrm{Al}_{2} \mathrm{O}_{3}, \mathrm{PbO}_{2}, \mathrm{Tl}_{2} \mathrm{O}_{3}$ (B) Write suitable equations to show their nature.

Solution: $\rightarrow$ CO $=$ Neutral $\rightarrow \mathrm{B}_{2} \mathrm{O}_{3}=$ Acidic Being acidic, it responds with bases to frame salts. It responds with $\mathrm{NaOH}$ to frame sodium...

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Explain the following reactions (a) Silicon is heated with methyl chloride at high temperature in the presence of copper; (b) Silicon dioxide is treated with hydrogen fluoride; (c) CO is heated with ZnO; (d) Hydrated alumina is treated with aqueous $\mathrm{NaOH}$ solution.

Solution: (a) Silicon is warmed with methyl chloride at high temperature within the sight of copper  A class of organosilicon polymers called methyl-subbed chlorosilane $\mathrm{MeSiCl}_{3},...

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Rationalize the given statements and give chemical reactions: – Lead (II) chloride reacts with $\mathrm{Cl}_{2}$ to give $\mathrm{PbCl}_{4}$. – Lead (IV) chloride is highly unstable towards heat. – Lead is known not to form an iodide, $\mathrm{Pbl}_{4}$.

Solution: - Lead is an individual from bunch 14 of the occasional table. The two oxidation situations with bunch shows are $+2$ and $+4$. The $+2$ oxidation state turns out to be more steady when...

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Depict the galvanic cell in which the reaction is: $Z n_{(s)}+2 \mathrm{Ag}_{(a q)}^{+} \rightarrow Z n_{(a q)}^{2+}+2 A g_{(s)}$ Further show: (i) which of the electrode is negatively charged? (ii) the carriers of the current in the cell. (iii) individual reaction at each electrode.

Solution: The galvanic cell relating to the given redox response can be displayed as: $\mathrm{Zn}\left|Z n_{(a q)}^{2+} \| A g_{(a q)}^{+}\right| \mathrm{Ag}$ (I) Zn anode is contrarily charged on...

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Given the standard electrode potentials, $A g^{+} / A g=0.80 \mathrm{~V}$ $\mathrm{Hg}^{2+} / \mathrm{Hg}=0.79 \mathrm{~V}$ $\mathrm{Mg}^{2+} / \mathrm{Mg}=-2.37 \mathrm{~V}$ $C r^{3+} / C r=-0.74 V$ Arrange these metals in their increasing order of reducing power.

Solution: The diminishing specialist is more grounded as the terminal potential declines. Subsequently, the expanding request of the lessening force of the given metals is as given underneath: Ag...

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Predict the products of electrolysis in each of the following: (i) An aqueous solution of $\mathrm{AgNO}_{3}$ with silver electrodes (ii) An aqueous solution $\mathrm{AgNO}_{3}$ with platinum electrodes (iii) A dilute solution of $\mathrm{H}_{2} \mathrm{SO}_{4}$ with platinum electrodes (iv) An aqueous solution of $\mathrm{CuCl}_{2}$ with platinum electrodes.

Solution: (I) In fluid arrangement, AgNO3 ionizes to give Ag+(aq) and NO3–(aq) particles.   \[AgN03\left( aq \right)\text{ }\to \text{ }Ag+\left( aq \right)\text{ }+\text{ }NO3\left( aq...

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Using the standard electrode potentials given in Table 8.1, predict if the reaction between the following is feasible: (a) $F e_{(a q)}^{3+}$ and $I_{(a q)}^{-}$ (b) $A g_{(a q)}^{+}$and $C u_{(s)}$ (c) $F e_{(a q)}^{3+}$ and $C u_{(s)}$ (d) $A g_{(s)}$ and $F e_{(a q)}^{3+}$ (e) $B r_{2}(a q)$ and $F e_{(a q)}^{2+}$

Solution: (a) $F e_{(a q)}^{3+}$ and $I_{(a q)}^{-}$ $2 F e_{(a q)}^{3+}+2 I_{(a q)}^{-} \rightarrow 2 F e_{(a q)}^{2+}+I_{2(s)}$ Oxidation half response: $2 I_{(a q)}^{-} \rightarrow I_{2}(s)+2...

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In Ostwald’s process for the manufacture of nitric acid, the first step involves the oxidation of ammonia gas by oxygen gas to give nitric oxide gas and steam. What is the maximum weight of nitric oxide that can be obtained starting only with 10.00 g. of ammonia and 20.00 g of oxygen?

Solution: The reasonable response is as given underneath: $4 \mathrm{NH}_{3(g)}+5 \mathrm{O}_{2}(g) \rightarrow 4 \mathrm{NO}_{(g)}+6 \mathrm{H}_{2} \mathrm{O}_{(g)}$ $4 N H_{3}=4 \times 17...

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Refer to the periodic table given in your book and now answer the following questions: (a) Select the possible non – metals that can show disproportionation reaction? (b) Select three metals that show disproportionation reaction?

Solution: One of the responding components consistently has a component that can exist in somewhere around 3 oxidation numbers. (I) The non - metals which can show disproportionation responses are...

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Balance the following equations in basic medium by ion-electron method and oxidation number methods and identify the oxidising agent and the reducing agent. (a) $P_{4}$ (s) $+$ $O H_{(a q)}^{-} \rightarrow$ $P H_{3}(g)+$ $H P O_{2}^{-}(a q)$ (b) $N_{2} H_{4}(l)+C l O_{3(a q)}^{-} \rightarrow N O_{(g)}+C l_{(g)}^{-}$ (c) $\mathrm{Cl}_{2} \mathrm{O}_{7}(\mathrm{~g})+\mathrm{H}_{2} \mathrm{O}_{2}(a q) \rightarrow \mathrm{ClO}_{2}^{-}(a q)+\mathrm{O}_{2}(g)+H_{(a q)}^{+}$

Solution:

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Balance the following redox reactions by ion – electron method : (a) $M n O_{4}^{-}(a q)+I_{(a q)}^{-} \rightarrow \operatorname{MnO}_{2}(s)+I_{2}(s)$ (Basic medium) (b) $\mathrm{MnO}_{4}^{-}(a q)+\mathrm{SO}_{2}(\mathrm{~g}) \rightarrow \mathrm{Mn}_{(a q)}^{2+}+\mathrm{H}_{2} \mathrm{SO}_{4}^{-}$(Acidic medium) (c) $\mathrm{H}_{2} \mathrm{O}_{2}(\mathrm{aq})+\mathrm{Fe}_{(a q)}^{2+} \rightarrow \mathrm{Fe}_{(a q)}^{3+}+\mathrm{H}_{2} \mathrm{O}_{(l)}$ (Acidic medium) (d) $\mathrm{Cr}_{2}^{2-} \mathrm{O}_{7}(\mathrm{aq})+\mathrm{SO}_{2}(\mathrm{~g}) \rightarrow \mathrm{Cr}_{(a q)}^{3+}+\mathrm{SO}_{(a q)}^{2-}$ (Acidic medium)

Solution: (a) $M n O_{4}^{-}(a q)+I_{(a q)}^{-} \rightarrow \operatorname{MnO}_{2}(s)+I_{2}(s)$ Stage 1 The two half responses are given beneath: Oxidation half response: $I_{(a q)} \rightarrow...

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Consider the reactions: (a) $\mathrm{H}_{3} \mathrm{PO}_{2}(a q)+4 \mathrm{AgNO}_{3}(\mathrm{aq})+2 \mathrm{H}_{2} \mathrm{O}_{(l)} \rightarrow \mathrm{H}_{3} P O_{4}(a q)+4 \mathrm{Ag}_{(s)}+$ $4 \mathrm{HNO}_{3}(a q)$ (b) $H_{3} P O_{2}(a q)+2 C u S O_{4}(a q)+2 H_{2} O_{(l)} \rightarrow H_{3} P O_{4}(a q)+2 C u_{(s)}+$ $H_{2} S O_{4}(a q)$ (c) $\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{CHO}_{(l)}+2\left[\mathrm{Ag}\left(\mathrm{NH}_{3}\right)_{2}\right]_{(a q)}^{+}+3 \mathrm{OH}_{(a q)}^{-} \rightarrow \mathrm{C}_{6} \mathrm{H}_{5} \mathrm{COO}_{(a q)}^{-}+2 \mathrm{Ag}_{(s)}+$ $4 \mathrm{NH}_{3}(\mathrm{aq})+2 \mathrm{H}_{2} \mathrm{O}_{(l)}$ (d) $\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{CHO}_{(\mathrm{l})}+2 \mathrm{Cu}_{(a q)}^{2+}+5 \mathrm{OH}_{(a q)}^{-} \rightarrow$ No change is observed What inference do you draw about the behavior of $\mathrm{Ag}^{+}$and $C u^{2+}$ from these reactions?

Solution: $\mathrm{Ag}^{+}$and $C u^{2+}$ acts as oxidizing specialist in responses (I) and (ii) individually. In response (iii), $\mathrm{Ag}^{+}$oxidizes $\mathrm{C}_{6} \mathrm{H}_{5}...

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Why does the following reaction occur? $X e O_{6(a q)}^{4-}+2 F_{(a q)}^{-}+6 H_{(a q)}^{+} \rightarrow X e O_{3}(g)+F_{2(g)}+3 \mathrm{H}_{2} \mathrm{O}_{(l)}$ What conclusion about the compound $\mathrm{Na}_{4} \mathrm{XeO}_{6}$ (of which $\mathrm{XeO}_{6}^{4-}$ is a part) can be drawn from the reaction?

Solution: $X e O_{6(a q)}^{4-}+2 F_{(a q)}^{-}+6 H_{(a q)}^{+} \rightarrow X e O_{3(g)}+F_{2(g)}+3 H_{2} O_{(l)}$ The oxidation no. of Xe decreases from $+8$ in $\mathrm{XeO}_{6}^{4-}$ to $+6$ in...

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Consider the reactions : $2 S_{2} O_{3(a q)}^{2-}+I_{2(s)} \rightarrow S_{4} O_{6(a q)}^{2-}+2 I_{(a q)}^{-}$ $S_{2} O_{3(a q)}^{2-}+2 B r_{2(l)}+5 \mathrm{H}_{2} \mathrm{O}_{(l)} \rightarrow 2 S O_{4(a q)}^{2-}+4 B r_{(a q)}^{-}+10 H_{(a q)}^{+}$ Why does the same reductant, thiosulphate react differently with iodine and bromine?

Solution: The normal oxidation no. of $\mathrm{S}$ in $\mathrm{S}_{2} \mathrm{O}_{3}^{2-}$ is $+2$. The normal oxidation no. of $\mathrm{S}$ in $S_{4} \mathrm{O}_{6}^{2-}$ is $+2.5$. The oxidation...

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Identify the substance oxidised, reduced, oxidising agent and reducing agent for each of the following reactions: (a) $2 \mathrm{AgBr}_{(s)}+\mathrm{C}_{6} \mathrm{H}_{6} \mathrm{O}_{2}(\mathrm{aq}) \rightarrow 2 \mathrm{Ag}_{(s)}+2 \mathrm{HBr}_{(\mathrm{aq})}+\mathrm{C}_{6} \mathrm{H}_{4} \mathrm{O}_{2}(\mathrm{aq})$ (b) $H C H O_{(l)}+2\left[A g\left(N H_{3}\right)_{2}\right]_{(a q)}^{+}+3 O H_{(a q)}^{-} \rightarrow 2 A g_{(s)}+H C O O_{(a q)}^{-}+$ $4 \mathrm{NH}_{3}(\mathrm{aq})+2 \mathrm{H}_{2} \mathrm{O}_{(l)}$ (c) $\mathrm{HCHO}_{(l)}+2 \mathrm{Cu}_{(a q)}^{2+}+5 \mathrm{OH}_{(a q)}^{-} \rightarrow \mathrm{Cu}_{2} \mathrm{O}_{(s)}+\mathrm{HCOO}_{(a q)}^{-}+3 \mathrm{H}_{2} \mathrm{O}_{(l)}$ (d) $N_{2} H_{4(l)}+2 \mathrm{H}_{2} \mathrm{O}_{2}(l) \rightarrow N_{2}(g)+4 \mathrm{H}_{2} \mathrm{O}_{(l)}$ (e) $\mathrm{Pb}_{(s)}+\mathrm{PbO}_{2(s)}+2 \mathrm{H}_{2} \mathrm{SO}_{4(a q)} \rightarrow 2 \mathrm{PbSO}_{4}(a q)+2 \mathrm{H}_{2} \mathrm{O}_{(l)}$

Solution: (a) $2 \mathrm{AgBr}_{(s)}+C_{6} H_{6} O_{2}(a q) \rightarrow 2 \mathrm{Ag}_{(s)}+2 \mathrm{HBr}_{(a q)}+C_{6} \mathrm{H}_{4} O_{2}(a q)$ $\mathrm{C}_{6} \mathrm{H}_{6}...

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How do you count for the following observations? (a) Though alkaline potassium permanganate and acidic potassium permanganate both are used as oxidants, yet in the manufacture of benzoic acid from toluene we use alcoholic potassium permanganate as an oxidant. Why? Write a balanced redox equation for the reaction. (b) When concentrated sulphuric acid is added to an inorganic mixture containing chloride, we get colourless pungent smelling gas HCl, but if the mixture contains bromide then we get red vapour of bromine. Why?

Solution: (a) While producing benzoic corrosive from toluene, alcoholic potassium permanganate is utilized as an oxidant because of the given reasons. (I) In an impartial medium, $O H^{-}$ions are...

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Whenever a reaction between an oxidisina adent and a reducina aqent is carried out, a compound of lower oxidation state is formed if the reducing agent is in excess and a compound of higher oxidation state is formed if the oxidising agent is in excess. J ustify this statement giving three illustrations. Justify the above statement with three examples.

Solution: When there is a response between lessening specialist and oxidizing specialist, a compound is framed which has lower oxidation number if the diminishing specialist is in abundance and a...

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Consider the reactions: (a) $6 \mathrm{CO}_{2}(g)+6 \mathrm{H}_{2} \mathrm{O}_{(l)} \rightarrow C_{6} H_{12} O_{6}(a q)+6 O_{2}(g)$ (b) $O_{3}(g)+H_{2} O_{2}(l) \rightarrow H_{2} O_{(l)}+2 O_{2}(g)$ Why it is more appropriate to write these reactions as : (a) $6 \mathrm{CO}_{2}(g)+12 \mathrm{H}_{2} \mathrm{O}_{(l)} \rightarrow C_{6} H_{12} \mathrm{O}_{6}($ aq $)+6 \mathrm{H}_{2} \mathrm{O}_{(l)}+6 \mathrm{O}_{2}(g)$ (b) $\mathrm{O}_{3}(\mathrm{~g})+\mathrm{H}_{2} \mathrm{O}_{2}(\mathrm{l}) \rightarrow \mathrm{H}_{2} \mathrm{O}_{(l)}+\mathrm{O}_{2}(\mathrm{~g})+\mathrm{O}_{2}(g)$ Also suggest a technique to investigate the path of the above (a) and (b) redox reactions

Solution: (a) Stage 1: $\mathrm{H}_{2} \mathrm{O}$ breaks to give $\mathrm{H}_{2}$ and $\mathrm{O}_{2}$. $2 \mathrm{H}_{2} \mathrm{O}_{(\mathrm{l})} \rightarrow 2...

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Calculate the oxidation number of sulphur, chromium and nitrogen in H2SO5, Cr2O2 and NOT. Suggest structure of these compounds. Count for the fallacy. nitrogen in H2SO5, Cr2O2 and NOT. Suggest structure of these compounds. Count for the fallacy.

Solution: O.N. of S in H2SO5. By traditional strategy, the O.N. of S in H2SO5 is 2 (+1) + x + 5 (- 2) = 0 or x = +8 This is outlandish on the grounds that the most extreme O.N. of S can't be more...

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