Solution 8: The following processes are involved in the extraction of zinc from zinc blende: (i) Concentration: Zinc blende ore is crushed and the concentration done by froth- floatation process....

Solution 8: The following processes are involved in the extraction of zinc from zinc blende: (i) Concentration: Zinc blende ore is crushed and the concentration done by froth- floatation process....

Solution 7: In the blast furnace reduction of iron oxides take place at different temperature ranges as shown below. At $500-800 \mathrm{~K}$ $$ \begin{array}{l} 3 \mathrm{Fe}_{2}...

Solution The common elements present in the anode mud are antimony, selenium, tellurium, silver, gold and platinum. These elements settle down under anode as anode mud because they are less reactive...

Solution 5: This can be explained thermodynamically, taking entropy and free energy changes into account (a) $C(s)+O_{2}(g) \rightarrow C O_{2}(g)$ (b) $2...

Solution 4: (i) Zone refining: This method is used for production of semiconductors and other metals of very high purity, e.g., $\mathrm{Ge}, \mathrm{Si}, \mathrm{B}, \mathrm{Ca}$ and $\mathrm{In}$....

Solution 4: (i) Zone refining: This method is used for production of semiconductors and other metals of very high purity, e.g., $\mathrm{Ge}, \mathrm{Si}, \mathrm{B}, \mathrm{Ca}$ and $\mathrm{In}$....

Solution 3: $\Delta_{f} G^{o}$ of $\mathrm{Cu}_{2} \mathrm{~S}$ is more negative than $\Delta_{f} G^{\circ}$ of $\mathrm{CS}_{2} \mathrm{H}_{2} S$. So $C_{u} 2 S$ can not be reduced by carbon or...

Solution 2: The role of depressant is to prevent one type of sulphide ore particles from forming the froth with air bubbles. $\mathrm{NaCN}$ is used as a depressant to separate lead sulphide (PbS)...

Solution Copper can be extracted by hydrometallurgy but not zinc, this is because $E_{Z n^{2}+Z n}^{o}=-0.76 \mathrm{~V}$ lower than that of $E_{\mathrm{Cu}^{2+} / C i}^{o}=-0.34 \mathrm{~V}$ Hence,...

Solution Yes, below $1350^{\circ} \mathrm{C}, \mathrm{Mg}$ can reduce $\mathrm{Al}_{2} \mathrm{O}_{3}$ and above $1350^{\circ} \mathrm{C}, \mathrm{Al}$ can reduce $\mathrm{MgO}$. This can be...

Solution This is explained on the basis of $\mathrm{Keq}$, the equilibrium constant. In the given redox reaction, all reactants and products are solids at room temperature, so, there is no...

Solution 2: Aluminium contains silica $\left(\mathrm{SiO}_{2}\right)$, iron oxide $\left(\mathrm{Fe}_{2} \mathrm{O}_{3}\right)$ and titanium oxide $\left(\mathrm{TiO}_{4}\right)$ as impurities....

Solution Ores which are magnetic in nature can be separated from non-magnetic gangue particles by magnetic separation method. For ex: ores of iron such as haemetite $\left(\mathrm{Fe} 2...

(i) $\left[\mathrm{Co}\left(\mathrm{H}_{2} \mathrm{O}\right)(\mathrm{CN})(\mathrm{en})_{2}\right]^{2+}$ Ans: Let us assume that the coordination number of Co is X. Therefore, we can write: $$...

Ans: These are explained below: (i) Unidentate ligand Ligands with only one donor site are called unidentate ligands. For example, $\mathrm{Cl}$ and $\mathrm{NH}_{3}$ are unidentate ligands. (ii)...

Ans: Let us assume that the coordination number of Co is X. Therefore, we can write: $$ \begin{array}{l} x+0+(-1)+2(0)=+2 \\ x-1=+2 \\ x=+3 \end{array} $$ So, the coordination number of cobalt is...

Ans: These are explained below: (i) Unidentate ligand Ligands with only one donor site are called unidentate ligands. For example, $\mathrm{Cl}$ and $\mathrm{NH}_{3}$ are unidentate ligands. (ii)...

Ans: All of them are explained below: (i) Coordination entity A central metal atom or anions connected to a set number of ions or molecules known as ligands comprises a coordination entity. For...

Ans: Let us see the reactions happening in both the cases. $$ \begin{array}{l} \left(\mathrm{NH}_{4}\right)_{2} \mathrm{SO}_{4}+\mathrm{FeSO}_{4}+6 \mathrm{H}_{2} \mathrm{O} \rightarrow...

Ans: Werner's theory is the first theory to explain the nature of bonding in coordination compounds. The main postulates of this theory are: (i) Two types of valencies, primary and secondary...

Ans: We are given the overall stability constant $\left(\beta_{s}\right)=2.1 \times 10^{13}$. The overall complex dissociation equilibrium constant is the reciprocal of the overall stability...

Ans: The formula of Tetraamminediaquacobalt (III) chloride is $$ \left[\mathrm{Co}\left(\mathrm{H}_{2} \mathrm{O}\right)\left(\mathrm{NH}_{3}\right)_{4}\right] \mathrm{Cl}_{3} $$ (ii) Potassium...

Solution 10 percent $w / w$ solution of glucose in water means $10 g$ glucose and $90 \mathrm{~g}$ of water. $10 \mathrm{~g}$ of glucose $=\frac{10}{180}=0.0555$ moles And $90 \mathrm{~g}$ of...

solution $-\frac{\text { mass }}{\text { density }}=\frac{100}{1.504}=66.5 \mathrm{~mL}$ Molarity of solution $$ \begin{array}{l} =\frac{\text { moles of sloution } \times 1000}{\text { Volume of...

Solution 4: $68 \%$ nitric acid by mass means that $68 \mathrm{~g}$ mass of nitric acid is dissolved in $100 \mathrm{~g}$ mass the solution. Molar mass of $\mathrm{HNO}_{3}=63 \mathrm{~g}...

Solution 3: (i) Mole Fraction: It is defined as the ratio of the number of moles of the solute to the total number of moles in the solution. If $\mathrm{A}$ is the number of moles of solute...

Solution Solution of hydrogen in palladium and dissolved gases in minerals

Solution $$ \begin{array}{l} \text { Given } \mathrm{V}=450 \mathrm{~mL}=0.45 \mathrm{~L} \\ =37^{\circ} \mathrm{C}=310 \mathrm{~K} \\ \mathrm{R}=8.314 \mathrm{kPaL} \mathrm{k}^{-1}...

Solution Given $\Delta \mathrm{Tb}=100-99.63=3.37^{\circ}$ Mass of water w1 $=500 \mathrm{~g}$ Molar mass of water, $\mathrm{M}_{1}=18 \mathrm{~g} \mathrm{~mol}^{-1}$ Molar mass of sucrose,...

Ans: By knowing the density of an unknown metal and the dimension of its unit cell, the atomic mass of the metal can be determined. Let 'a' be the edge length of a unit cell of a crystal, 'd' be the...

Ans: The number of nearest neighbors of any constituent particle present in the crystal lattice is called its coordination number.

(i) Hexagonal close-packing and cubic close-packing? Ans: A 2-d hexagonal close-packing contains two types of triangular voids (a and b) as shown in figure 1. Let us call this 2-D structure as layer...

Ans: Higher the melting point, greater are the intermolecular forces of attraction between the atoms of a molecule and greater is the stability of that molecule. A substance with higher melting...

Ans: It is given that the density of niobium, $\mathrm{d}=8.55 \mathrm{gcm}^{-3}$ Atomic mass, $M=93 \mathrm{gmol}^{-1}$ As the lattice is bcc type, the number of atoms per unit cell, $z=2$ Let the...

Ans: It is given that the atoms of $\mathrm{Q}$ are present at the corners of the cube. Therefore, number of atoms of $Q$ in one unit cell $=8 \times(1 / 8)=1$ It is also given that the atoms of...

Ans: It is given that the edge length, $\mathrm{a}=4.07 \times 10^{-8} \mathrm{~cm}$ and density is $\mathrm{d}=$ $10.5 \mathrm{~g} \mathrm{~cm}^{3}$ As the lattice is foc type, the number of atoms...

Ans: Higher the melting point, greater are the intermolecular forces of attraction between the atoms of a molecule and greater is the stability of that molecule. A substance with higher melting...

Ans: It is given that the density of niobium, $\mathrm{d}=8.55 \mathrm{gcm}^{-3}$ Atomic mass, $M=93 \mathrm{gmol}^{-1}$ As the lattice is bcc type, the number of atoms per unit cell, $z=2$ Let the...

Ans: It is given that the atoms of $\mathrm{Q}$ are present at the corners of the cube. Therefore, number of atoms of $Q$ in one unit cell $=8 \times(1 / 8)=1$ It is also given that the atoms of...

Ans: It is given that the density of niobium, $\mathrm{d}=8.55 \mathrm{gcm}^{-3}$ Atomic mass, $M=93 \mathrm{gmol}^{-1}$ As the lattice is bcc type, the number of atoms per unit cell, $z=2$

Ans: It is given that the atoms of $\mathrm{Q}$ are present at the corners of the cube. Therefore, number of atoms of $Q$ in one unit cell $=8 \times(1 / 8)=1$ It is also given that the atoms of...

Ans: It is given that the atoms of $\mathrm{Q}$ are present at the corners of the cube. Therefore, number of atoms of $Q$ in one unit cell $=8 \times(1 / 8)=1$ It is also given that the atoms of...

Ans: It is given that the edge length, $\mathrm{a}=4.07 \times 10^{-8} \mathrm{~cm}$ and density is $\mathrm{d}=$ $10.5 \mathrm{~g} \mathrm{~cm}^{3}$ As the lattice is foc type, the number of atoms...

Ans: Edge length, $a=3.61 \times 10^{-6} \mathrm{~cm}$ As the lattice is fcc type, the number of atoms per unit cell, $z=4$ Atomic mass, $\mathrm{M}=63.5 \mathrm{~g} \mathrm{~mol}^{-1}$ We also know...

Ans: Semiconductors are substances having conductance in the intermediate range $10^{-6}$ to $10^{4}$ ohm $^{-1} \mathrm{~m}^{-1}$. The two main types of semiconductors are: (i) n-type semiconductor...

(i) Ge doped with In Ans: Ge (a group 14 element) is doped with In (a group 13 element). Therefore, a hole will be created and the semiconductor generated will be a p-type semiconductor. (ii) B...

Ans: Let the number of oxide $\left(\mathrm{O}^{2-}\right)$ ions be $\mathrm{x}$. So, number of octahedral voids $=x$ It is given that two out of every three octahedral holes are occupied by ferric...

Ans: It is given that $\mathrm{NaCl}$ is doped with $10^{3} \mathrm{~mol} \%$ of $\mathrm{SrCl}_{2}$. This means that $100 \mathrm{~mol}$ of $\mathrm{NaCl}$ is doped with $10^{3} \mathrm{~mol}$ of...

(i) What is the length of the side of the unit cell? Ans: For cubic close-packed structure: $$ \begin{array}{l} \mathrm{a}=2 \sqrt{2} \mathrm{r} \\ \Rightarrow 2 \sqrt{2}=125 \mathrm{pm} \\ =353.55...

Ans: It is given that $\mathrm{NaCl}$ is doped with $10^{3} \mathrm{~mol} \%$ of $\mathrm{SrCl}_{2}$. This means that $100 \mathrm{~mol}$ of $\mathrm{NaCl}$ is doped with $10^{3} \mathrm{~mol}$ of...

(i) What is the length of the side of the unit cell? Ans: For cubic close-packed structure: $$ \begin{array}{l} \mathrm{a}=2 \sqrt{2} \mathrm{r} \\ \Rightarrow 2 \sqrt{2}=125 \mathrm{pm} \\ =353.55...

Ans: As isotropic solid has the same value of physical properties when measured along different directions. Therefore, the given solid, having the same value of refractive index along all...

Ans: Similar to liquids, glass has a tendency to flow, though very slowly. Therefore, glass is considered as a super cooled liquid. This is the reason that glass windows and doors are slightly...

Ans: The intermolecular forces of attraction that are present in solids are very strong, The constituent particles of solids have fixed positions i.e., they are rigid. Hence, solids have a definite...

Ans: The intermolecular forces of attraction that are present in solids are very strong. The constituent particles of solids cannot move from their positions i.e., they have fixed positions....

Ans: The given properties are the properties of a covalent or network solid. Therefore, the given solid is a covalent or network solid. Examples of such solids include diamond ( $\mathrm{C}$ ) and...

Ans: Potassium sulphate $\rightarrow$ ionic solid Tin Metallic $\rightarrow$ solid Benzene $\rightarrow$ Molecular (non-polar) solid Urea $\rightarrow$ Polar molecular solid Ammonia $\rightarrow$...

(i) Hexagonal and monoclinic unit cells Ans: Hexagonal unit cell: For a hexagonal unit cell $$ \begin{array}{l} a=b \neq c \\ \text { and } \alpha=\beta= \\ y=120^{\circ} \end{array} $$ Monoclinic...

Ans: The six parameters that characterize a unit cell are as follows. (i) Its dimensions along the three edges, $a, b$, and $c$. These edges may or may not be equal. (ii) Angles between the edges....

Ans: The significance of a lattice point is that each lattice point represents one constituent particle of a solid which may be an atom, a molecule (group of atom), or an ion.

Ans: The ccp lattice is formed by the atoms of the element $\mathrm{N}$. Here, the number of tetrahedral voids generated is equal to twice the number of atoms of the element $\mathrm{N}$. According...

A compound is formed by two elements $\mathrm{M}$ and $\mathrm{N}$. The element $\mathrm{N}$ forms ccp and atoms of M occupy $1 / 3 r d$ of tetrahedral voids. What is the formula of the compound?

Ans: In a square close-packed layer, the molecule is in contact with four of its neighbours, Therefore, the two-dimensional coordination number of a molecule in a square close packed layer is $4 .$

Ans: (i) An atom located at the corner of a cubic unit cell is shared by eight adjacent unit cells. Therefore, 1 / 8 th portion of the atom is shared by one unit cell. (ii) An atom located at the...

(i) $\mathrm{ZnS}$, Ans: ZnS shows Frenkel defect. (ii) $\mathrm{AgBr}$ Ans: AgBr shows Frenkel defect as well as Schottky defect.

Ans: When a solid is heated, vacancy defects can arise. A solid crystal is said to have vacancy defects when some of the lattice sites are vacant. Vacancy defect leads to a decrease in the density...

Ans: It is given that density of the element, $d=2.7 \times 10^{3} \mathrm{~kg} \mathrm{~m}^{-3}$ Molar mass, $M=2.7 \times 10^{-2} \mathrm{~kg} \mathrm{~mol}^{-1}$ Edge length, $\mathrm{a}=405...

Ans: Ferromagnetic substances would make better permanent magnets. In solid state, the metal ions of ferromagnetic substances are grouped together into small regions. These regions are called...

Ans: An n-type semiconductor conducts because of the presence of extra electrons. Therefore a group 14 element can be converted to n-type semiconductor by doping it with a group 15 element.

Ans: The colour develops because of the presence of electrons in the anionic sites. These electrons absorb energy from the visible part of radiation and get excited. For example, when crystals of...

Ans: When a cation of higher valence is added to an ionic solid as an impurity to it, the cation of higher valence replaces more than one cation of lower valence so as to keep the crystal...

i. $\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{NH}_{2}+\mathrm{HCl} \rightarrow$ Ans: n-propylammonium chloride ii. $\left(\mathrm{C}_{2} \mathrm{H}_{5}\right)_{3}...

Solution 9: \begin{tabular}{l} \hline $\mathrm{P} \square=23.8 \mathrm{~mm} \mathrm{Hg}$ \\ $\mathrm{W} 2=50 \mathrm{~g}, \mathrm{M}_{2}($ urea $)=60 \mathrm{~g} \mathrm{~mol}^{-1}$ \\ $\mathrm{w}...

Solution 7: $$ \mathrm{KH}=1.67 \times 10_{8} \mathrm{~Pa} $$ $$ \begin{array}{l} \hline P_{A}^{o}=450 \mathrm{~mm}, P_{B}^{o}=700 \mathrm{~mm}, P_{\text {total }}=600 \mathrm{~mm} \\ \text { As...

Ans: The complex will be $\left[\mathrm{Co}\left(\mathrm{C}_{2} \mathrm{O}_{4}\right)_{8}\right]^{3}$. Oxidation state of cobalt will be $=x-6=-3$ The oxidation state is $=+3$ Coordination number...

Ans: The carbon metal linkages in metal carbonyls are characterized by both s and p. M-Ca bond consists of a donation into an empty metal orbital of a lone pair of electrons on the carbonyl carbon....

Ans: In $\left[\mathrm{Cr}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3 v}$ the oxidation state of $\mathrm{Cr}$ is in $+3$ oxidation state, which will cause the configuration of $\mathrm{Cr}$ as...

(i) $\quad\left[\mathrm{CO}\left(\mathrm{NH}_{3}\right)_{6}\right] \mathrm{Cl}_{3}$ Ans: The IUPAC name of the compound is Hexaamminecobalt(III) chloride. (ii)...

Solution 4: $0.25$ molal aqueous solution to urea means that Moles of urea $=0.25$ mole Mass of solvent $(\mathrm{NH} 2 \mathrm{CONH} 2)=60 \mathrm{~g} \mathrm{~mol}^{-1}$ $\therefore 0.25$ mole of...

solution (b) $30 \mathrm{~mL}$ of $0.5 \mathrm{M} \mathrm{H}_{2} \mathrm{SO}_{4}$ diluted to $500 \mathrm{~mL}$. Solution 3: (a) Molar mass of $\mathrm{Co}\left(\mathrm{NO}_{3}\right)_{2}, 6...

Solution 2: $30 \%$ by mass of $\mathrm{C} 6 \mathrm{H} 6$ in $\mathrm{CCl} 4 \Rightarrow 30 \mathrm{~g} \mathrm{C} 6 \mathrm{H} 6$ in $100 \mathrm{~g}$ solution $\therefore$ Number of moles of...

Solution Mass percentage of $$ \begin{array}{l} C_{6} H_{6}=\frac{\text { Mass of } \mathrm{C}_{6} \mathrm{H}_{6}}{\text { Total mass of the solution }} \times 100 \% \\ =\frac{\text { Mass of }...

(i) Tetra phosphorus decoxide $\left(\mathrm{P}_{4} \mathrm{O}_{20}\right)$ (ii)Ammonium phosphate $\left(\mathrm{NH}_{4}\right)_{3} \mathrm{PO}_{4}$ (iii) $\mathrm{SiC}$ (iv) $\mathrm{I}_{2}$ (v)...

Ans: The arrangement of the constituent particles makes glass different from quartz. In glass, the constituent particles have short range order, but in quartz, the constituent particles have both...

Ans: Amorphous solids are the solids that have their constituent particles of irregular shape and have short range order. These solids are isotropic in nature and melt over a range of temperature....

Solution Soaps work in soft water. However, they are not effective in hard water. In contrast, synthetic detergents work both in soft water and hard water. Therefore, synthetic detergents are better...

Solution Alitame is a high potency sweetener. It is difficult to control the sweetness of food while using alitame as an artificial sweetener.

Solution Artificial sweetening agents such as saceharin, alitame, and aspartame can be used in preparing sweets for diabetie paticats. Question 19: What problem arises in using alitame as artificial...

Solution Artificial sweetening agents are chemicals that sweeten food. However, unlike natural sweeteners, they do not add calories to our body. They do not harm the human body. Some artificial...

Solution Aspartame becomes unstable at cooking temperature. This is the reason why its use is limited to cold foods and drinks.

Solution Food preservatives are chemicals that prevent food from spoilage due to microbial growth. Table salt, sugar, vegetable oil, sodium benzoate (ChHsCOONa), and salts of propanoic acid are...

Solution Tincture of iodine is a $2-3$ percent solution of wodine in alcohol - water mixture, It is applied to wounds as an antiseptic.

Solution The main constituents of dettol are chloroxylenol and a-terpineol. CC1=CC(O)=CC(C)C1Cl CC1=CCC(C(C)(C)Br)CC1 Chatisiars a-ticyanat

Solution Phenol can be used as an antiseptic as well as a disinfectant. $0.2$ peroent solution of phenol is used as an antiseptic, while 1 per cent of its solution is used as a disinfectant.

Solution Cimetidine and rantidine are better antacids as they control the root eause of acidity. These drugs prevent the interaction of histamine with the receptors present in the stomach walls....

Solution Antiseptics and disinfectants are effective against micro-organisms. However, antiseptics are applied to the living tisswes such as wounds, cuts, ulcers, and diseased skin surfaces, while...

Solution 9: Antibiotics that are effective against a wide range of gram-positive and gram-negative bacteria are known as broad spectrum antibiotics. Chloramphenicol is a broud spectrum antibiotic....

Solution \&: Anti-depressant drugs are needed to counteract the effect of depression. These drugs inhibit Enzymes catalysing the degradation of the neurotransmitter, noradrenaline. As a result, the...

Solution Specific drugs affect particular receptors. Antacids and anti-allergie drugs work on different receptors. This is the reason why antacids and anti-allergic drugs do not interfere with each...

Solution Either of the following forces can be involved in holding drugs to the active sites of enzymes, (i) Ionic bonding (ii) Hydrogen bonding (iii) Dipole - dipole interaction (iv) van der Waals...

Solution The use of chemicals for therapeutic effect is called chemotherapy. For example: the use of chemicals in the diagnosis, prevention, and treatment of diseases

Solution The macromolecules chosen as drug targets are carbohydrates, lipids, proteins, and nucleic acids,

Solution In medicinal chemistry, drug targets refer to the key molecules involved in certain metabolic pathways that result in specific diseases, Carbohydrates, proteins, lipids, and nucleic acids...

Solution The classification of drugs and the reasons for classification are as follows: (i) On the basis of pharmacological effect: This classification provides doctors the whole range of drugs...

i. $\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{NH}_{2}+\mathrm{HCl} \rightarrow$ Ans: n-propylammonium chloride ii. $\left(\mathrm{C}_{2} \mathrm{H}_{5}\right)_{3}...

Ans: Considering the inductive effect of alkyl groups $\mathrm{NH}_{3}, \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{NH}_{2}$ and $\left(\mathrm{C}_{2} \mathrm{H}_{5}\right)_{2} \mathrm{NH}$ can be...

Ans: It is because the chemical $\left(\mathrm{C}_{9} \mathrm{H}_{10} \mathrm{O}\right)$ generates a derivative of 2,4 -dnp and reduces the reagent of Tollen. The chemical must thus be an aldehyde....

$\mathrm{H}_{3} \mathrm{C} \longrightarrow{\mathrm{C}}_{2}^{\mathrm{H}_{2}} \mathrm{CHO}+\mathrm{H}_{3} \mathrm{C} \longrightarrow \stackrel{\mathrm{H}_{2}}{\mathrm{C}}-\mathrm{CHO} \longrightarrow...

(i) $\mathrm{CH}_{3} \mathrm{CO}\left(\mathrm{CH}_{2}\right)_{4} \mathrm{CH}_{3}$ Ans: The IUPAC name of the given compound is Heptan-2-one and its common name is Methyl n-pentyl ketone. (ii)...

(i) 3-Methylbutanal Ans: The structure of 3-Methylbutanal is given below: CC(C)CC=O (ii) p-Nitropropiophenone Ans: The structure of p-Nitropropiophenone is given below: (viii) Hex-2-en-4-ynoic acid...

Ans: The IUPAC name of the given compound is 4-Methylpentanal, (ii) $\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{COCH}\left(\mathrm{C}_{2} \mathrm{H}_{5}\right) \mathrm{CH}_{2} \mathrm{CH}_{2}...

Solution 5: Functional groups present in the molecule are: Hy trophobic part (i) Ether, and (ii) primary alcoholic group wime yodansu cion 10 "odididu Lice onun: r.toning $\mathrm{R}-\mathrm{C}=$...

Solution Sodiam palmoie (Soup) Glyiery palmitate Olyserol (ii) Glyceryl oleses Görerd

Solution A large number of pcople are suffering from diseases such as diabetes and obesity. These people cannot take normal sugar i.e., sucrose as it is hamful for them. Therefore, artificial...

Solution The given statement refers to the classification of pharmacological effects of the drug. This is because any drug that is used to counteract the effects of excess acid in the stomach is...

Solation Most drugs when taken in doses higher than recommended may cause harmful effects and sometimes, may even lead to death. Hence, a doctor should always be consulted before taking any medicine

Solution Soap molecules form micelles around an oil droplet (dirt) in such a way that the hydrophobic parts of the stearate ions attach themselves to the oil droplet and the hydrophilic parts...

Solution Soaps get precipitated in hard water, but not in sott water. Therefore, soups can be used for checking the hardness of water- However, synthetic detergents do not get procipitated cither in...

Solution Detergents that can be degraded by bicteria are called biodegradable detergents. Such detergents have straight hydrocarbon chains, For example: sodium lauryl sulphate Detergents that cannot...

Solution 21: (i) Cationic detergent Cationic detergents are quatemary ammonium salts of acetates, chlorides, or bromides. These are called cationic detergents because the cationic part of these...

Solution Soaps work in soft water. However, they are not effective in hard water. In contrast, synthetic detergents work both in soft water and hard water. Therefore, synthetic detergents are better...

Solution Alitame is a high potency sweetener. It is difficult to control the sweetness of food while using alitame as an artificial sweetener.

Solution Artificial sweetening agents such as saceharin, alitame, and aspartame can be used in preparing sweets for diabetie paticats.

Solution Aspartame becomes unstable at cooking temperature. This is the reason why its use is limited to cold foods and drinks.

Soluthon Food preservatives are chemicals that prevent food from spoilage due to microbial growth. Table salt, sugar, vegetable oil, sodium benzoate (ChHsCOONa), and salts of propanoic acid are...

Solution Tincture of iodine is a $2-3$ percent solution of wodine in alcohol - water mixture, It is applied to wounds as an antiseptic.

Solution 13: The main constituents of dettol are chloroxylenol and a-terpineol. CC1=CC(O)=CC(C)C1Cl CC1=CCC(C(C)(C)Br)CC1 Chatisiars a-ticyanat

Solution Phenol can be used as an antiseptic as well as a disinfectant. $0.2$ peroent solution of phenol is used as an antiseptic, while 1 per cent of its solution is used as a disinfectant.

Solution Antacids such as sodium hydrogen carbonate, magnesium hydroxide, and aluminium hydroxide work by neutralising the excess hydrochloric acid present in the stomach. However, the root cause...

Solution Antiseptics and disinfectants are effective against micro-organisms. However, antiseptics are applied to the living tisswes such as wounds, cuts, ulcers, and diseased skin surfaces, while...

Solution 9: Antibiotics that are effective against a wide range of gram-positive and gram-negative bacteria are known as broad spectrum antibiotics. Chloramphenicol is a broud spectrum antibiotic....

Solution Antibiotics that are effective against a wide range of gram-positive and gram-negative bacteria are known as broad spectrum antibiotics. Chloramphenicol is a broud spectrum antibiotic....

Solution Anti-depressant drugs are needed to counteract the effect of depression. These drugs inhibit Enzymes catalysing the degradation of the neurotransmitter, noradrenaline. As a result, the...

Solution Specific drugs affect particular receptors. Antacids and anti-allergie drugs work on different receptors. This is the reason why antacids and anti-allergic drugs do not interfere with each...

Solution Either of the following forces can be involved in holding drugs to the active sites of enzymes, (i) Ionic bonding (ii) Hydrogen bonding (iii) Dipole - dipole interaction (iv) van der Waals...

Solution The use of chemicals for therapeutic effect is called chemotherapy. For example: the use of chemicals in the diagnosis, prevention, and treatment of diseases

Solution 4: A medicine can bind to more than one receptor site. Thus, a medicine may be toxic for some receptor sites. Further, in most cases, medicines cause harmful effects when taken in higher,...

Solution 3; The macromolecules chosen as drug targets are carbohydrates, lipids, proteins, and nucleic acids,

Solation In medicinal chemistry, drug targets refer to the key molecules involved in certain metabolic pathways that result in specific diseases, Carbohydrates, proteins, lipids, and nucleic acids...

Solution 1: The classification of drugs and the reasons for classification are as follows: (i) On the basis of pharmacological effect: This classification provides doctors the whole range of drugs...

Ans: The hydrolysis of a nucleotide of DNA having thymine as its base give thymine $\beta$-D-2 deoxyribose and phosphoric acid as products.

Ans: The water-soluble compounds cannot retain in human body due to constant excretion through urine. The vitamin $\mathrm{C}$ is water soluble component in our body and thus, cannot be stored,

Ans: When we boil the egg, the proteins present within them gets denatured and thus, goes under coagulation. The excess water present is then absorbed by the coagulated protein through $\mathrm{H}$...

Ans: The linkage formed between two monosaccharide units through an oxygen atom by the loss of a water molecule is known as glycosidic linkage. For example: Sucrose molecule has a glycosidic linkage...

Ans: The classification is given as; Monosaccharides: Ribose, 2-deoxyribose, galactose and fructose, Disaccharides: Maltose and lactose.

Ans: The two main functions of carbohydrates (polysaccharides) in plants are: - Starch serves as storage molecules. - Cellulose is used to build the cell wall.

Ans: The carbohydrates that reduce Fehling's solution and Tollen's reagent are known as reducing sugars. All the monosaccharide and disaccharides are reducing sugars, except for sucrose.

Ans: Monosaccharides are the most basic units of the biomolecules. They cannot be hydrolyzed further to give simpler units. They are then classified on the basis of; - Number of C atoms: trioses,...

Ans: There are two types of amino acids in the human body: Essential amino acids: - They are required by the body but cannot be synthesized within. - These must be taken up via food. - For example,...

Ans: The reactions of D-glucose which cannot be explained by its open structure are; - $2,4-\mathrm{DNP}$ test, Schiff"s test and reaction with $\mathrm{NaHSO}_{4}$ to form hydrogen sulphite as...

Ans: Vitamins are classified on the basis of their solubility in water or fat as follows; - Vitamins such as A, D, E and K are soluble in fats and oils but not in Water. - $B$ group vitamins...

Ans: Denaturation results in unfolding of globules and uncoiling of helixes. During this process, secondary and tertiary proteins are destroyed but the primary ones remain unaltered. Sometimes,...

Ans: The proteins that catalyze the biological reactions or biological catalysts are known as enzymes. They are very specific in nature and catalyze only a particular reaction for a particular...

Ans: Considering a DNA molecule; it has double stranded structure in which adenine always pairs up with thymine and cytosine always pairs up with guanine through $\mathrm{H}$ - bonding. Thus, when...

Ans: The hydrolysis of a nucleotide of DNA having thymine as its base give thymine $\beta$-D-2 deoxyribose and phosphoric acid as products.

Ans: The water-soluble compounds cannot retain in human body due to constant excretion through urine. The vitamin $\mathrm{C}$ is water soluble component in our body and thus, cannot be stored,

Ans: When we boil the egg, the proteins present within them gets denatured and thus, goes under coagulation. The excess water present is then absorbed by the coagulated protein through $\mathrm{H}$...

Ans: In this reaction, arenediazonium salt reacts with aromatic amino compounds (in acidic medium) or a phenol (in alkaline medium) to form brightly coloured azo compounds. The reaction generally...

'Hofmann's bromamide reaction Ans: When an amide is treated with bromine in alkali solution, it is converted to a primary amine that has one carbon atom less than the starting amide. This reaction...

Ans: The process of conversion of a primary aromatic amino compound into a diazonium salt, is known as diazotization. This process is carried out by adding. an aqueous solution of sodium nitrite to...

Ans: Both aliphatic and aromatic primary amines when warmed with chloroform and an alcoholic solution of $\mathrm{KOH}$, produces isocyanides or carbylamines which have a very unpleasant odour. This...

Ans: The three types of amines can be distinguished by the Heinsberg test. In this test, the amine is shaken with benzene sulphonyl chloride $\left(\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{SO}_{2}...

Ans: $$ \mathrm{CH}_{3} \mathrm{NO}_{2} \stackrel{\text { snilhe }}{\longrightarrow} \mathrm{CH}_{3} \mathrm{NH}_{2} \stackrel{\text { oHCl. KOHs }}{\rightarrow} \mathrm{CH}_{3} \mathrm{NC}...

Ans: $$ \begin{array}{l} \mathrm{CH}_{3} \mathrm{NH}_{2} \stackrel{\mathrm{HONO}}{-\mathrm{N}_{2}-\mathrm{H}_{4} \mathrm{O}} \longrightarrow \mathrm{CH}_{3} \mathrm{OH}...

Ans: $$ \mathrm{CH}_{3} \mathrm{COOH} \stackrel{\mathrm{LiAl}_{4}}{\rightarrow \mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OH}} \underset{\mathrm{ONPH}_{1}}{\mathrm{P}+\mathrm{H}_{3}} \rightarrow...

i. Methylamine and dimethylamine Ans: Methylamine and methylamine can be distinguished by carbylamine test. $\mathrm{CH}_{3} \mathrm{NH}_{2}+\mathrm{CHCl}_{3}+3 \mathrm{KOH}...

i. $\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{NH}_{2}, \mathrm{C}_{6} \mathrm{H}_{5} \mathrm{NH}_{2}, \mathrm{NH}_{3}, \mathrm{C}_{6} \mathrm{H}_{5} \mathrm{CH}_{2} \mathrm{NH}_{2}...

Ans. An aldehyde group is present in glucose. It, on the other hand, does not react with sodium hydrogen sulphite to generate bisulphite addition products. This is because this reaction takes place...

Ans. As hydrochloric acid is present in the stomach lining; this causes the stomach to have a low $\mathrm{pH}$ value. The $\mathrm{pH}$ of the stomach is about $1-2$ which is extremely acidic, this...

Ans. When sucrose is hydrolyzed, the sign of rotation changes from dextro $(+)$ to laevo $(-)$, and the result is known as invert sugar.

Ans: Antacids such as sodium hydrogen carbonate, magnesium hydroxide, and aluminium hydroxide function by neutralising excess hydrochloric acid in the stomach. However, the underlying reason for...

Ans: Depression is caused by a lack of noradrenaline. Antidepressant medications are required to treat this condition. They stop noradrenaline breakdown enzymes from working. As a result,...

Ans: Detergents containing branched chain hydrocarbons are non-biodegradable because bacteria have difficulty degrading them. As a result, straight chain hydrocarbon detergents are favoured over...

Ans: Soaps with sodium salts are made by heating fat (the glycerol ester of a fatty acid) with an aqueous sodium hydroxide solution. Soaps containing sodium and potassium are the only ones that are...

Ans: Estrogen and progesterone are female hormones that are linked to ovulation and menstruation in women. They also play a role in pregnancy. Birth control pills contain a mix of both hormones and...

i. Identify the compound. Ans: The compound given in the structure is bithionol. It is an antiseptic ii. What is its use? Ans: Being an antiseptic, bithionol is used to cure wounds and treat minor...

Solution: (a) Half life, $t_{\frac{1}{2}}=\frac{0.693}{k}$ $$ \begin{array}{l} =\frac{0.693}{200 \mathrm{~s}^{-1}} \\ =3.47 \times 10^{-3} s \text { (Approximately) } \end{array} $$ (b)...

Solution: (a) The differential rate equation will be $$ \begin{array}{l} 5.07 \times 10^{-5}=k[0.20]^{x}[0.30]^{y} \\ 5.07 \times 10^{-5}=k[0.20]^{x}[0.10]^{y} \\ 1.43 \times...

Solution: (a) Avg rate of reaction between the time intervals, 30 to 60 seconds, $$ \begin{array}{l} =\frac{\left.d E_{\text {ster }}\right]}{d t} \\ =\frac{0.31-0.17}{60-30} \\ =\frac{0.14}{30} \\...

Solution: When a temperature of $10^{\text {a }}$ rises for a chemical reaction then the rate constant increases and becomes near to double of its original value. The temperature effect on the rate...

Solution: By decreasing the interfacial tension between two liquids that form the emulsion, emulsifiers stabilize an emulsion. Long-chain molecules with polar groups are emulsifiers. Examples:...

Solution: Emulsion is defined as the colloidal solution in which both the dispersed phase and dispersion medium are liquids. There are two types of emulsions: (a) Oil in water type: Here, water is...

(i) when a beam of light is passed through a colloidal sol. (ii) an electrolyte, $\mathrm{NaCl}$ is added to hydrated ferric oxide

Solution: Colloids can be classified on various basis: (i) By components we mean the dispersed phase and dispersion medium i.e. the physical state of the components. Therefore, we can have eight...

Solution: Protein molecules of high molecular masses are termed as enzymes. Colloidal solutions are formed when these are dissolved in water. These are complex, nitrogenous organic compounds...

Solution: (i) In multi-molecular colloids, the colloidal particles are an aggregate of atoms or small molecules with a diameter of less than $1 \mathrm{~nm}$. Van der Waal's forces of attraction are...

Solution: (i) Lyophilic sols: Lyophilic sols are colloidal sols that are formed by mixing substances such as gum, gelatin, starch, etc. with a suitable liquid (dispersion medium). These sols are...

Solution: Effect of pressure: Adsorption increases with an increase in pressure, since adsorption is a reversible process and is accompanied by a decrease in pressure. Effect of temperature: In...

Ans: Point defect - As the name implies, point faults occur exclusively at or around a single lattice point. They are not spatially expanded in any way. Stoichiometric defect do not affect the...

Ans: Non-stoichiometric flaws are those imperfections that do not affect the crystalline substance's stoichiometry. The anionic sites contain electrons, which cause the color to develop. As a result...

Ans: A higher-valence cation is introduced as an impurity in an ionic solid. Less than 2 higher-valance ions replace two or more lower-valance cations or ions. Few locations are left empty in order...

Ans: In the corner of a cubic unit cell, eight neighboring unit cells share the same atom. One unit cell therefore shares $1 / 8$ th of the atom. (b) body centre Ans: Each unit cell in a cubic unit...

Ans: Let the edge of the unit cell = a pm Number of atoms present per unit cell $=Z$ The atomic mass of the element is represented as $=\mathrm{M}$. So, the volume of the unit cell $=(a p...

Ans: This indicates that the arrangement of spheres in every fourth layer is the same as the arrangement of spheres in every first layer, and so on. Ultimately, this results in

Ans: This indicates that the arrangement of spheres in every third layer is the same as that in the first. As a result, a hexagonal tight packing is obtained.

Ans: A soft lubricant, graphite is an excellent conductor of electricity because its electrons are delocalized and free to flow about in the crystal structure. In addition to being an excellent...

Ans: A soft lubricant, graphite is an excellent conductor of electricity because its electrons are delocalized and free to flow about in the crystal structure. In addition to being an excellent...

Ans: Glass is a supercooled liquid since it flows. Bottom glass panes are thicker than top glass panes.