Explore topic-wise InterviewSolutions in Current Affairs.

This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.

1.	Give common boiling point order of H_(2)O, COCl_(4) Ethanol and Ether.
Answer» Solution :Ether `(308 K)LT COCl_(4)(347.7)lt` Ethanol `(351.3K)lt H_(2)O (373 K)`

2.	Give classification of substances according to Faraday.
Answer» Solution :The classification of SUBSTANCE according to Faraday is as under, (1) Electrolytes substances (2) Non-electrolytes substances Faraday classified the electrolytes substances into two SUB, types, (1) STRONG electrolytes substance (2) Weak electrolytes substance

3.	Give classification of nomenclature with example.
Answer» SOLUTION :ISOMER of ALKENE and EXAMPLE are FOLLOWS :

4.	Give classification of organic compounds
Answer» Solution :The CLASSIFICATION of organic COMPOUNDS on the BASE of their STRUCTURE are as under:

5.	Give classification of hydrocarbons based on carbon-carbon bonds.
Answer» SOLUTION :

6.	Give classification of hdyrcarbons.
Answer» SOLUTION :In HYDROCARBON, there are HYDROGENS and carbons. CLASSIFICATION is as FOLLOWS :

7.	Give classification of given groups into O/P and m-directing groups : -CHO, -C_(2)H_(5), -SO_(3)H and -NH_(2).
Answer» SOLUTION :m-directing GROUPS : `CHO, -SO_(3)H` o/p - directing groups : `C_(2)H_(5), -NH_(2)`

8.	Give classification and examples of salts an the base of hydrolysis .
Answer» SOLUTION :Salts of strong acid and strong base : These salts do not hydrolyse and the solutionsof salts FORMED from strong acids and bases are neutral.i.e., `NaCl, NaNO_3 , KNO_3 , K_2SO_4` etc. In short ,the saltscontaining `NaCl, NaNO_3 ,KNO_3 , K_2SO_4` positive ions and `Cl^(-) , Br^(-) , NO_3^(-1) , ClO_4^(-) , SO_4^(2-)` an negative ions. Salts of WEAK acid and strong base : In this type of salts the anion of weak acid GET hydrolyse and from weak acid and solution become basic. e.g., `NaCH_3COO, K_3PO_4 , Na_2CO_3 , KHCO_3, NaOBr` etc. weak acid strong base salts solution are basic and `pH gt 7`. Salts of strong acid and weak base : In this type , the hydrolysis is occur by cation of weak base and from weak base and solution become acidic e.g., `NH_4Cl, NH_4NO_3 , CuSO_4 , FeCl_3, MgSO_4 , Ca(NO_3)_2`solutionare acidic and pH `lt` 7 . Salts of weak acid and weak base :This type of solution are almost neutral or very less acidic or basic. e.g., `CH_3COONH_4 , HCOONH_4` etc.

9.	Give chemical reaction to convert bromoethane into alkane having double carbon atoms.
Answer» Solution :`UNDERSET("Bromomethane")(CH_(3)CH_(2)Br)-2Na underset(underset("Wurtz")("REACTION"))overset(overset("Anhydrous")("ether"))RARR underset("n-butane")(CH_(3)CH_(2)CH_(2)CH_(3))+2NaBr`

10.	Give chemical reactions for the following :
Answer» Solution :(i) When benzene react with `Cl_(2)` in PRESENCE of sun light, (II) When benzene react with `Cl_(2)` in presence of anhydros `AlCl_(3)` in dark and cold condition. (III) when benzene react with `Cl_(2)` in presence of anhydrous `AlCl_(3)`. (IV) When PHENOL is heated in presence of Zn powder.

11.	Give chemical reaction of aluminum with dilute HCl ?
Answer» Solution :Aluminum on DILUTION with HCl produces hydrogen GAS LOW concentration. `2Al+6HCl + 12H_2O to 2(Al(H_2O)_6)Cl_3+3H_2`

12.	Give chemical reaction for the preparation of water gas (Synthetic gas).
Answer» SOLUTION :`C_((s)) + H_2O_((G)) OVERSET"473-1273 K"to ubrace(CO_((g)) + H_(2(g)))_("Water GAS")` .

13.	Give chemical reaction for the preparation of water gas and producer gas.
Answer» Solution :It is prepared by the passage of steam over hot coke. The mixture of CO and `H_2` thus produced is known as water gas or synthesis gas. `C_((s)) + H_2O_((g)) OVERSET"473 K - 1273 K"to ubrace(CO+H_2)_("Water gas")` When air is USED instead of steam, a mixture of CO and `N_2` is produced, which is called PRODUCER gas. `2C_((s)) + O_(2(g)) + 4N_(2(g)) overset"1273 K"to ubrace(2CO_((g)) + 4N_(2(g)))_("Producer gas")`

14.	Give chemical reaction for the preparation of producer gas.
Answer» Solution :`2C_((s)) + O_(2(g)) + 4N_(2(g)) OVERSET"1273 K"to 2CO_((g)) + 4N_(2(g))`

15.	Give chemical reaction for the preparation of borax bead.
Answer» Solution :`UNDERSET"PRISMATIC borax"(Na_2B_4O_7. 10H_2O) OVERSET(DELTA)to underset"Borax glass"(Na_2B_4O_7) + 10H_2O` `Na_2B_4O_7 oversetDeltato underset"Borax BEAD"(2NaBO_2) + B_2O_3`

16.	Give chemical reaction fo the following conversion :
Answer» SOLUTION :(i) ACETONE from PROPENE :

17.	Give chemical reaction for preparing pure CO.
Answer» Solution :On small scale PURE CO is prepared by DEHYDRATION of formic ACID with concentrated`H_2SO_4` at 373 K `HCOOH underset("Conc." H_2SO_4)overset"373 K to 413 K"to CO + H_2O`

18.	Give chemical properties of elements of group-13.
Answer» Solution :Due to small size of boron, the sum of its first three ionization enthalpies is very high. This prevents it to form +3 ions and forces it to form only covalent compounds. But as we move from B to AI, the sum of the first three ionisation enthalpies of Al considerably decreases and is therefore able to form `Al^(3+)` ions. In fact, aluminium is a highly electro-positive metal. However, down the group, due to poor shielding effect of intervening d and f orbitals, the increased effective nuclear charge holds ns electrons tightly (responsible for inert pair effect) and there by, restricting their PARTICIPATION in bonding. As a result of this, only p-orbital electron may be involved in bonding. In fact in Ga, In and Tl, both +1 and +3 oxidation states are observed. The relative stability of +1 oxidation state progressively increases for heavier elements : Al `lt` Ga `lt` In `lt` TI. In thallium +1 oxidation state is predominant where as the +3 oxidation state is highly oxidising in character.The compounds in +1 oxidation state, as expected from energy considerations, are more ionic than those in +3 oxidation state. In trivalent state, the number of electrons around the central atom in a molecule of the compounds of these elements (e.g., boron in `BF_3`) will be only six. Such electron deficient molecules have tendency to accept a pair of electrons to achieve stable electronic configuration and thus, behave as LEWIS acids. The tendency to behave as Lewis acid decreases with the increase in the size down the group. `BCl_3` easily ACCEPTS a lone pair of electrons from ammonia to form `BCl_3 · NH_3`. In trivalent state most of the compounds being covalent are hydrolysed in water. For example, the trichlorides on -hyrolysis in water form tetrahedral `[M(OH)_4]` species, the hybridisation state of element M is `sp^3`. Aluminium chloride in acidified aqueous solution forms octahedral `[Al(H_2O_6]^(3+)`ion. In this complex ion the 3d orbitals of Al are involved and the hybridisation state of Al is `sp^3d^2`. (i)Reactivity towards air : Boron is UNREACTIVE in crystalline form. Aluminium forms a very thin oxide layer on the surface which protects the metal from further attack. Amorphous boron and aluminium metal on heating in air form `B_2O_3` and `Al_2O_3` respectively. With dinitrogen at high temperature they form nitrides. `2E_((s)) + 3O_(2(g)) oversetDeltato 2E_2O_(3(s))` `2E_((s)) + N_(2(g)) oversetDeltato 2EN_((s))` (E=Elements) The nature of these oxides varies down the group. Boron trioxide is acidic and reacts with basic (metallic) oxides forming metal borates. Aluminium and gallium oxides are amphoteric and those of indium and thallium are basic in their properties. (ii) Reactivity towards acids and alkalies : Boron does not react with acids and alkalies even at moderate temperature, but aluminium dissolves in mineral acids and aqueous alkalis and thus shows amphoteric character. Aluminium dissolves in dilute HCland liberates dihydrogen. `2Al_((s)) + 6HCl_((AQ)) to 2Al_((aq))^(3+) + 6Cl_((aq))^(-) + 3H_(2(g))` However, concentrated nitric acid renders aluminium passive by forming a protective oxide layer on the surface. Aluminium also reacts with aqueous alkali and liberates dihydrogen. `{:(2Al_((s)) + 2NaOH_((aq)) + 6H_2O_((l))),(""darr),(2Na^(+)[Al(OH)_4]_(aq)^(-) + 3H_(2(g))),("Sodium ""tetrahydroxoaluminate (III)"):}` (iii) Reactivity towards halogens : These elements react with halogens to form trihalides (except Tl `I_3`) `2E_((s))+3X_(2(g)) to 2EX_(3(s))` (X=F,Cl,Br,I)

19.	Give chemical properties of water.
Answer» Solution :Water reacts with a large number of substances some of the important REACTIONS are given below. (i)Amphoteric NATURE : It has the ability to act as an acid as well as a base i.e., it behaves as an amphoteric substance. In the Brönsted sense it acts as an acid with `NH_3` and a base with `H_2S` . `H_2O_((l))+NH_(3(aq)) hArr OH_((aq))^(-) + NH_(4(aq))^(+)` `H_2O_((l))+H_2S_((aq))hArr H_3O_((aq))^(+) + HS_((aq))^(-)` (iii) Hydrolysis Reaction : Due to high dielectric constant, it has a very strong hydrating tendency. It dissolves many ionic compounds. However, certain covalent and some ionic compounds are hydrolysed in water. `P_4O_(10(s)) + 6H_2O_((l)) to 4H_3PO_(4(aq))` `SiCl_(4(l)) + 2H_2O_((l)) to SiO_(2(s)) +4HCl_((aq))` `N_((s))^(3-) +3H_2O_((l)) to NH_(3(G)) + 3OH_((aq))^(-)` (iv) Hydrates Formation: From aqueous solutions many salts can be crystallised as hydrated salts. Such an association of water is of different types viz., (i)Coordinated water e.g., `[Cr(H_2O)_6]^(3+) 3Cl^(-)` (ii)interstitial water e.g., `BaCl_2. 2H_2O` (iii) hydrogen-bonded water e.g., `[CU(H_2O)_4]^(2+) SO_4^(2-) . H_2O` in `CuSO_4 . 5H_2O`

20.	Give chemical formula, name and structure of gamexene.
Answer» SOLUTION :`C_(6)H_(6)Cl_(6)` : BENZENE hexachloride Structure :

21.	Give chemical formula and structure of acetophenone.
Answer» SOLUTION :CHEMICAL FORMULA : `C_(6)H_(5)COCH_(3) -=C_(8)H_(8)` Structure :

22.	Give Charle.s Law.
Answer» SOLUTION : ..At CONSTANT PRESSURE, VOLUME and fixed amount of any gas is directly proportional to its absolute temperature... `V PROP n` (P constant) `V=K_(2)T, (V)/(T)=` constant.

23.	Give Charle.s law in brief.
Answer» Solution :Charles. law and Formula : Charles. and Gay LUSSAC performed several experiments on gases independently to imporove upon hot air balloon technology. Simple Gay Lussac.s law : Their investigations SHOWED that for a fixed mass of a gas at constnat pressure, volume of a gas increases on increasing temperature and decreases on cooling. Charles and Gay Lussac they found that - ..for each degree rise in temperature, volume of a gas increases by `(1)/(273.15)` of the original volume `(V_(0))` of the gas at `0^(@)C`. .. Thus, temperature volume `0^(@)C=V_(0)` and temperature volume `t^(@)C=V_(t)` then, `V_(t)=V_(0)+((t)/(273.15))V_(0)` `therefore V_(t)=V_(0)(1+(t)/(273.15)) ""` ......(Eq. -i) `therefore V_(t)=V_(0)((273.15+t)/(273.15)) ""`....(Eq. -ii) But `(273.15+t)""^(@)C=T_(1)k` So, `273.15^(@)C=T_(0)=273.15k` Thus `V_(t)=V_(0)((T_(1))/(T_(0))) ""`....(Eq. -iii) `therefore (V_(t))/(V_(0))=(T_(1))/(T_(0)) ""`....(Eq. -IV) OR`(V_(2))/(V_(1))=(T_(2))/(T_(1)) ""`....(Eq. - v) So, `(V_(2))/(T_(2))=(V_(1))/(T_(1))""`...(Eq. - vi) Thus `(V)/(T=` constant `k_(2) ""` .....(Eq. -vii) `therefore V=k_(2)T ""`.....(Eq. - viii) This (Equation - viii) is the mathermatical expression for Charles. law. Charles. law : He states that pressure remaining constant, the volume of a fixed mass of a gas is directly PROPORTIONAL to its absolute temperature. Characteristics and Graph of Charle.s Law : For all gases, at any given pressure, graph of volume vs remperature (in celsius) is as under. the graph is a straight line. the graph extending to zero volume. Slopes of lines obtained at different pressure are differnt `(p_(1), p_(2), p_(3),.....)`. Each line intercepts the temperature axis at `- 273.15^(@)C`. But at zero volume all the lines MEET the temperature axis at `- 273.15^(@)C`. All the lines are isobar because pressure is constant.

24.	Give can der Waal.s equation.
Answer» <P> SOLUTION :`(p+(an^(2))/(V^(2)))(V-nb)=NRT`

25.	Give C-C single bond length and double bond in fullerene.
Answer» SOLUTION :Fullerene has single and DOUBLE bonds with C-C distances of 143.5pm and 138.3 PM RESPECTIVELY.

26.	Give calculation of gas constant R for unit of bar Lit mol^(-1)K^(-1) in ideal gas equation.
Answer» <P> Solution :R = 0.08314 BAR L `mol^(-1)K^(-1)`. pV = nRT and `R=(pV)/(NT)` `R=(("1 bar")(22.71L))/((1mol)(273.15 K))` where, p = 1 bar V = 22.71 L T = 273.15 K n = 1 mole. R = 0.083141 bar L `mol^(-1)K^(-1)` `R=8.0314x10^(-2)` bar L `mol^(-1)K^(-1)`.

27.	Give brief on abundance of alkali metal and alkaline earth metal in earth crust.
Answer» Solution : Among the alkali metals sodium and potassium are abundant and lithium, rubidium and caesium have MUCH lower abundances. Francium is highly radioactive, its longest-lived isotope `""^(223)Fr` has a half-life of only 21 minutes. Of the alkaline earth metals calcium and magnesium rank fifth and sixth in abundance respectively in the earth.s crust. Strontium and BARIUM have much lower abundances. Beryllium is rare and radium is the rarest of all comprising only `10^(-10)` per CENT of IGNEOUS ROCKS.

28.	Give brief note on oxides of alkaline earth metal elements.
Answer» SOLUTION : The alkaline earth metals burn in oxygen to form the monoxide, MO which, except for BeO, have rock-salt structure. The BeO is essentially covalent in nature. The enthalpies of formation of these oxides are quite high and consequently they are very stable to HEAT. BeO is AMPHOTERIC while oxides of other elements are IONIC in nature.

29.	Give brief information on Ionization Enthalpy and Hydration Enthalpy of alkali metal (Group I).
Answer» SOLUTION :The ionization enthalpies of the alkali metals are considerably low and decrease down the group from Li to CS. This is because the effect of increasing size OUTWEIGHS the increasing nuclear charge, and the outermost ELECTRON is very well screened from the nuclear charge. The hydration enthalpies of alkali metal ions decrease with increase in ionic sizes. `Li^(+) gt Na^(+) gt K^(+) gt Rb^(+) gt Cs^(+)` `Li^(+)`has maximum degree of hydration and for this REASON lithium salts are mostly hydrated, e.g.,LiCl. `2H_(2)O`

30.	Give brief note on acidic nature of alkyne.
Answer» Solution : s-orbit is more negative than p-orbit, so electronegativity increases as s-orbit increases. So electronegativity order : `SP C gt sp^(2) C gt sp^(3) C` Due to this reason, sp carbon attract mximum bonded electron towards itself. And thus, hydrogen attached directly to the sp carbon has more acidity than hydrogen of ALKANE and alkene. `underset("Acidic H " larr "Neutral H")(-=C-H gt =C-H gt- C-H)` "H attached to the carbon having triple bond of alkyne is more acidic and rest hydrogens are not acidic in nature". Only H attached to triple bond of `HC -= CH, CH_(3)C-=CH, CH_(3)CH_(2)C-=CH` is acidic in nature. So in `R-C-=C-H` only terminal H is of acidic natured. And H of R is not acidic in nature. Also, `R-C-=C-R` no H is of acidic nature. Chemical reaction of acidic hydrogen or reaction which shows acidic nature of H attached to Carbon having triple bond : Both terminal H of acetelene is weak acidic in nature. ETHYNE on reaction o with strong base of sodium metal at high temperature and sodamid `(NaNH_(2))` it gives ethynide (acetelide) product. `underset("ETHYN")(H-C-=C-H)+Na overset(475 K)rarr underset("etheynide")underset("Monosodium")(H-C-=C^(-)Na^(+))+ (1)/(2)H_(2)`(Eq. (i)) `H-C-=C^(+)Na+Na overset(475 K)rarr underset("Disodium ethynide")(Na^(+)C^(-)-=C^(-)Na^(+))+(1)/(2)H_(2)`(Eq. (ii)) `H-C-=C-H+underset("Sodamide")(NaNH_(2)) overset(NH_(3))rarr H-C-=CNa + (1)/(2)H_(2)`(Eq. (iii)) `H-C-=C-H+2NaNH_(2)overset(NH_(3))rarr ""(+)NaC^(-) -=C^(-)Na^(+)+H_(2)` (Eq. (iv)) Acidic order of hydrogen attached with carbon : (i) `underset(~10^(-25))(HC-=CH) gt underset(~10^(-85))(H_(2)C=CH_(2)) lt underset(~10^(-40))(H_(3)C-CH_(3))` (ii)`HC-=CH gt CH_(3)C-=CH gt CH gt gt CH_(3)C-=C CH_(3)` There is no acidic hydrogen present in `R-C-=CR, CH_(3)C-=C-CH_(3)`, so they do not show any reaction with Na or `NaNH_(2)`

31.	Give brief information on atomic and ionic radius of alkali metal (Group I).
Answer» Solution : The alkali metal atoms have the largest sizes in a particular period of the periodic table. With increase in ATOMIC number, the atom becomes larger. The monovalent ions `(M^(+))`are SMALLER than the parent atom. The atomic and ionic radii of alkali metals increase on moving down the group i.e., they increase in SIZE while going from Li to CS.

32.	Give brief explanations on hydroxides of alkali metals.
Answer» Solution : Oxides of alkali metals are easily hydrolysed by WATER to form hydroxides. `M_(2)O+H_(2)O to 2M^(+) +2OH^(+)` `M_(2)O_(2)+2H_(2)O to 2M^(+) +2OH^(-)+H_(2)O_(2)` `2MO_(2)+2H_(2)O to 2M^(+) +2OH^(-) +H_(2)O_(2)+O_(2)` The hydroxides which are obtained by the reaction of the oxides with water are all white crystalline SOLIDS. The alkali metal hydroxides are the strongest of all bases and DISSOLVE freely in water with evolution of much heat on account of intense hydration.

33.	Give brief explanation on ionisation enthalpy of alkaline earth metals (Group-2) elements.
Answer» SOLUTION : The alkaline earth METALS have low IONIZATION enthalpies due to fairly large size of the atoms. Since the atomic size increases down the group, their ionization enthalpy decreases. The first ionisation enthalpies of the alkaline earth metals are higher than those of the corresponding Group-1 metals. This is due to their small size as compared to the corresponding alkali metals. It is interesting to note that the SECOND ionisation enthalpies of the alkaline earth metals are smaller than those of the corresponding alkali metals.

34.	Give brief explanation on carbonates, sulphates and nitrate compounds of alkaline earth metal elements.
Answer» Solution : Salts of Oxoacids : The alkaline earth metals also form salts of oxoacids. Some of these are : (a) Carbonate compounds (b) SULPHATE compounds and (c) Nitrate compounds (a) Carbonates : Carbonates of alkaline earthmetals are insoluble in water and can be precipitated by addition of a sodium or ammonium carbonate solution to a solution of a soluble salt of these metals. The solubility of carbonates in water decreases as the atomic number of the metal ion increases. All the carbonates decompose on heating to give carbon dioxide and the oxide. Beryllium carbonate is unstable and can be kept only in the atmosphere of `CO_(2)`. The thermal stability increases with increasing cationic size. (b) Sulphates : The sulphates of the alkaline earth metals are all white solids and stable to heat. `BeSO_(4), and MgSO_(4)` are readily soluble in water, the solubility decreases from `CaSO_(4)` to `BaSO_(4)`. The greater hydration ENTHALPIES of `Be^(2+)` and `Mg^(2+)` ions overcome the lattice enthalpy factor and therefore their sulphates are soluble in water. (c) Nitrates : The nitrates are made by dissolution of the carbonates in DILUTE nitric acid. MAGNESIUM nitrate crystallises with six molecules of water, whereas barium nitrate crystallises as the anhydrous salt. This again shows a decreasing tendency to form hydrates with increasing size and decreasing hydration enthalpy. All of them decompose on heating to give the oxide like lithium nitrate. `2M(NO_(3))_(2) to 2MO+4NO_(2)+O_(2) (M=Be,Mg,Ca,Sr,Ba)`

35.	Give brief about production of cement and write its properties and uses.
Answer» Solution :The raw materials for the manufacture of cement are limestone and clay. When clay and lime are strongly heated together they fuse and react to form .cement clinker.. This clinker is mixed with 2-3% by weight of gypsum `(CaSO_(4)*2H_(2)O)` to form cement. Thus important ingredients present in Portland cement are dicalcium silicate `(Ca_(2)SiO_(4)) 26%`, tricalcium silicate `(Ca_(2) SiO_(2)) 51%` and tricalcium aluminate `(Ca_(3)Al_(2)O_(6))11%`. PROPERTIES (Setting of Cement) : When mixed with water, the setting of cement takes place to GIVE a hard mass. This is due to the hydration of the molecules of the constituents and their rearrangement. The purpose of ADDING gypsum is only to slow down the process of setting of the cement so that it gets sufficiently hardened.

36.	Give breif information about the types of smog.
Answer» Solution :The word smog is derived from smoke and fog. This is the most common example of air pollution that occurs in many cities throughout the world. There are TWO types of smog: - (i) CLASSICAL smog : This type of smog occurs in cool humid climate. It is a mixture of smoke, fog and sulphur dioxide. It is also called as reducing smog because it is chemically reducing mixture. (ii) Photochemical smog : This type of smog occurs in warm, DRY and sunny climate. It is produce due to the action sunlight on unsaturated hydrocarbons and nitrogen dioxide PRODUCED by automobiles and FACTORIES. It is also called as oxidising smog because it has high concentration of oxidising agent.

37.	Give brief about structure of ethye (Acetylene).
Answer» Solution :Molecular formula of ethyne is `C_(2)H_(2)`. It is a first member of alkyne series. Ethyne has sp HYBRIDIZATION of exited carbon and both the carbon possess non-hybridized 2p orbitals. Two sp orbitals are linear in shape and sp orbitas are `bot 2p_(x) bot 2p_(y)`. Bond formation in ethyne (`sigma`-bond) : Carbon carbon sigma `(sigma)` bond is obtained by the head-on overlapping of the two sp hybridised orbitals of the two carbon atoms. The remaining sp hybridized orbital of each carbon atoms undergoes overlapping along the internuclear axis with the 1s orbital of each of the two hydrogen atoms forming two C-H sigma bonds. H-C-C bond angle is of `180^(@)`. Each carbon has two unhybridised p-orbitals which are perpendicular to each other as well as to the plane of the C-C sigma bond. `sigma`-bond : H-C-C-H Arrangement of `pi`-bond : Two carbon atoms are perpendicular to each other and H-C-C-H are 2p orbitals of sigma bond edges. These 2p orbitals are parallel to each other. `2p_(x)\|\|2p_(x)` and `2p_(y)\|\|2p_(y)`. These `2p_(x)-2p_(x)` and `2p_(y)-2p_(y)` overlap by side by side and form two `pi`-bonds. The following diagram justifies these : So the simple structure of ethyne is as following. CHARACTERISTICS of ethyne structure : "Ethyne is linear molecule" `angleH - C-C=180^(@)` due to sp carbon. Ethyne has one C-C `sigma` and two `C-H sigma-` bond. Also it has two C-C `pi`-bonds. `C-=C` bond enthalpy `= 823 KJ mol^(-1)` C=C bond enthalpy `= 681 kJ mol^(-1)` C-C bond enthalpy `= 348 kJ mol^(-1)` `therefore` So order of bond strength is : `C-=C gt C=Cgt C-C` Bond length`alpha 1` / bond order `therefore` So order of bond length is : `C-=C lt C=C lt C-C` `(("120 pm"),("ethyne")) lt (("133 pm"),("ethene")) lt (("154 pm"),("ethane"))` In ethylene, cloud of two electrons of `pi`-bond is arranged as a cyclinderical symmetry around the axis of INTER nuclear two carbon.

38.	Give bond order of NO, NO^(+) , CN , CN^(-) and CO.
Answer» SOLUTION :

39.	Give bond order of H_(2)^(+), He_(2)^(+), He_(2)^(2+).
Answer» SOLUTION :

40.	Give bond enthalpies and bond length between carbon and carbon of alkane ?
Answer» SOLUTION :

41.	Give bond length in Hydrogen, ethan, ethen, ethyne.
Answer» SOLUTION :

42.	Give bond length between C-C of ethane, ethene, ethyneand benzene.
Answer» SOLUTION :`{:("Compund","Ethane","Ethene","ETHYNE","Benzene"),("C-C bond length","154 pm","133 pm","120 pm","139 pm"):}`

43.	Give bond angle and bond length of methane ?
Answer» Solution :The ANGLE is of `120^(@)` and BOND LENGTH between C-H is 112 pm.

44.	Give biological importance of sodium ion.
Answer» Solution : SODIUM ions are FOUND primarily on the outside of cells, being located in BLOOD PLASMA and in the interstitial fluid which surrounds the cells. These ions participate in the transmission of nerve signals, in regulating the flow of water across cell membranes and in the transport of sugars and AMINO acids into cells.

45.	Give bond angle and bond length of ethene.
Answer» Solution :Structure of ETHENE `C_(2)H_(4)` C-C bond LENGTH 134 pm bond ANGLE H - C - H = `117.6^(@)`, angle H - C - C = `121^(@)`

46.	Give beta-elimination of given alcohol reaction. (i) Propyl alcohol (ii) Isopropyl alcohol (iii) Cyclo hexanol (iv) tertiary-butyl alcohol.
Answer» SOLUTION :Alcohol treated with conc. `H_(2)SO_(4)`, on dehydration, alkene is formed also known as `beta`-elimination reaction. (i) `underset("Propane-1-ol")underset("(m-propyl-alcohol)")(CH_(3)CH_(2)CH_(2)OH) underset(Delta 443 K)overset("Conc. " H_(2)SO_(4))rarr underset("Propene")(CH_(3)H=CH_(2)+H_(2)O)` (ii)`underset("alcohol")underset("(isopropyl-ol)")underset("propane-2-ol")(CH_(3)CHOHCH_(3))underset(438-443 K)overset(H_(2)SO_(4))rarr underset("Propene")(CH_(3)CH=CH_(2)+H_(2)O)` (III) (iv) `underset((3^(@)" BUTYL alcohol"))underset("2,2-Dimethyl propane-2-ol")(H_(3)C-underset(OH)underset(\|)overset(CH_(3))overset(\|)(""^(alpha)C)-overset(beta)(CH_(3)))underset(Delta, 360 K)overset(H_(2)SO_(4))rarr underset("(very easily)")underset("2-Methyl propane")(H_(3)C-overset(CH_(3))overset(\|)(C)=CH_(2))` Note : (i) Rate of reaction `3^(@)`-Alcohol `gt 2^(@)`-Alcohol `gt 1^(@)`-Alcohol. (ii) dehydration reaction occurs in PRESENCE of `ZnCl_(2)` or anhydrous `Al_(2)O_(3)`.

47.	Give biological importance of calcium and magnesium.
Answer» Solution : An ADULT body contains about 25 g of Mg and 1200 g of Ca compared with only 5 g of iron and 0.06 g of copper. The daily requirement in the human body has been estimated to be 200-300 mg. All enzymes that utilise ATP in phosphate transfer require magnesium as the cofactor. The main pigment for the absorption of light in plants is chlorophyll which contains magnesium. About 99 % of body calcium is PRESENT in bones and teeth. It also plays important roles in neuromuscular function, interneuronal transmission, cell membrane integrity and blood coagulation. The calcium concentration in plasma is regulated at about 100 mg`L^(-1)`. It is MAINTAINED by two hormones - calcitonin and parathyroid hormone. The bone is not an inert and UNCHANGING substance but is continuously being solubilised and redeposited to the extent of 400 mg per day in man. All this calcium passes through the plasma.

48.	Give basic information about aromatic hydrocarbon.
Answer» Solution :These hydrocarbons are ALSO known as .arenes.. Since most of them posses pleasant odour GREEK, aroma meanng pleasant smelling), the CLASS of compounds was NAMED as .aromatic compounds.. Most of such compounds were found to contain benzene ring. Benzene ring is highly unsaturated but in a majority of reactions of aromatic compounds, the usaturation of benzene ring is RETAINED. Aromatic compounds containing benzene ring are known as benzenoids and those not containing a benzene ring are known as non-benzenoids. Some examples of arenes are given below :

49.	Give basic about cement.
Answer» Solution : Cement is an important BUILDING material. It was first introduced in England in 1824 by Joseph Aspdin. It is also called Portland cement because it resembles with the natural limestone quarried in the Isle of Portland, England. Cement is a PRODUCT obtained by COMBINING a material rich in lime, CaO with other material such as clay which CONTAINS silica, `SiO_(2)`, along with the OXIDES of aluminium, iron and magnesium

50.	Give Avogadro.s Law.
Answer» Solution :It STATES that - EQUAL VOLUMES of all GASES under the sasme conditions of temperature and pressure contain equal NUMBER of temperature...