1050 + Interview Questions in CLASS-11 IN GENERAL AWARENESS Page 20 InterviewSolution

951.	Which of the following exhibits only +3 oxidation state?A. `U`B. `Th`C. `Pa`D. `Ac`
Answer» Correct Answer - D Ac`(Z=89)` electronic configuration `[Rn]6d^(1)7s^(2)` shows `+3` oxidation state only.

Discussion

952.	Which of the following lanthanoids ions is diamagnetic?A. `Sm^(2+)`B. `Eu^(2+)`C. `Ce^(2+)`D. `Yb^(2+)`
Answer» Correct Answer - D Lanthanoid ion with no unpaired electrons is diamagnetic in nature. `Ce_(58)=[Xe]4f^(2)5d^(0)6s^(2)` `Ce^(2+)=[Xe]4f^(2)`(two unpaired electrons ) `Sm_(62)=[Xe]4f^(6)5d^(0)6s^(2)` `Sm^(2+)=[Xe]4f^(6)`(six unpaired electron) `Eu_(63)=[Xe]4f^(7)5d^(0)6s^(2)` `Eu^(2+)=[Xe]4f^(7)`(seven unpaired electron) `Yb_(70)=[Xe]4f^(14)5d^(0)6s^(2)` `Yb^(2+)=[Xe]4f^(14)`(no unpaired electrons) `:. Yb^(2)` is diamagnetic.

Discussion

953.	Among the following series of transition metals ions, the one where all metal ions have `3d^(2)` electronic configuration is:A. `Ti^(3+),V^(2+),Cr^(3+),Mn^(4+)`B. `Ti^(+),V^(4+),Cr^(6+),Mn^(7+)`C. `Ti^(4+),V^(3+),Cr^(2+),Mn^(3+)`D. `Ti^(2+),V^(3+),Cr^(4+),Mn^(5+)`
Answer» Correct Answer - D `Ti_(22)=3d^(2)4s^(2),Ti^(2+)=3d^(2)` `V_(23)=3d^(3)4s^(2),V^(3+)=3d^(2)` `Cr_(24)=3d^(4)4s^(2),Cr^(4+)=3d^(2)` `Mn_(25)=3d^(5)4s^(2),Mn^(5+)=3d^(2)`.

Discussion

954.	Among `K,Ca,Fe` and `Zn` the element which can form more than one binary compound with chlorine isA. `Fe`B. `Zn`C. `K`D. `Ca`
Answer» Correct Answer - A A binary compound is one made of tow different elements. These can be several of each element

Discussion

955.	Each group of the modern periodic table consists of a number of elements having the similar electronic configuration of the_____shell.A. pendultimateB. valenceC. outermostD. antepenulimate
Answer» Correct Answer - B It is the valence shell which controls the chemical behavior of the element.

Discussion

956.	On what basis the fungi were earlier included in the plant kingdom ?
Answer» Fungi have cell wall and are nonmotile like the plants.

Discussion

957.	Assertion : In Two-Kingdom classification system, bacteria, blue-green algae and fungi were placed under plants. Reason : These all organisms had cell wall in their cells.A. If both assertion and reason are true and the reason is the correct explanation of the assertion.B. If both assertion and reason are true but reason is not the correct explanation of the assertion.C. If assertion is true but reason is false.D. If both assertion and reason are false.
Answer» Correct Answer - A In two-Kingdom classification system bacteria, blue-green algae and fungi were placed under plants because all these organisms had cell wall in their cells.

Discussion

958.	Give reasons why fungi should not be included in Plant Kingdom.
Answer» Fungi differ from plants in their mode of nutrition, reserve food material and composition of cell walls. They are heterotrophic organisms which derive their nutrients mainly by absorption from the surrounding medium due to lack of chlorophyll. They are essentially the decomposers and mineralisers of the biospheres. The reserve food material is glycogen and fat as in animals. The cell wall is generally composed of chitin. Therefore, fungi should not be included in plant kingdom.

Discussion

959.	Asseration : Phycomycetes, are commonly known as sac-fungi. Reason : In Phycompyecetes, ascopore (sexual spores) are produced endogenously in sac like asci.A. If both assertion and reason and true and reason is the correct explanation of assertion.B. If both assertion and reason and true and reason is not the correct explanation of assertion.C. If assertion is true but reason is false.D. If both assertion and reason are false.
Answer» Correct Answer - D Asscomycetes are produced endogenoulsy in sac like asci. Members of phycomcetes are found in aquatic habitats and on decaying wood in moist and damp places or as obligate parasites on plants.

Discussion

960.	Give a comparative account of the classes of Kingdom Fungi under the following: (i) Mode of nutrition (ii) Mode of reproduction
Answer» `{:("Class of fungi",,"Mode of Nutrition",,"Mode of reproduction"),("Class. Oomycetes",,"Mostly aquatic and obligate",,"Sexual reproduction result in"),(,,"parasites on plants.",,"the formation of Oospores."),("Class. Zygomycetes",,"Mostly Saprophytes",,"Isogametes fuse to form zygospores."),("Class. Ascomycetes",,"They are saprophytes, parasites",,"Sexual spores are called Ascospores"),(,,"or coprophilous (growing on dung)",,),("Class. Basidiomycetes",,"They are Saprophytes or parasites.",,"Sexual spores are called Basidiospores."),("Class . Deuteromycetes",,"Mostly parasites",,"Sexual reproduction not known"):}`

Discussion

961.	Which of the following classes of kingdom Fungi are characterised by the presence of coenocytic, multinucleate and branched mycelium?A. BasidiomycetesB. PhycomycetesC. AscomycetesD. Deuteromycetes
Answer» Correct Answer - B Phycomycetes are characterised by the presence of coenocytic multinucleate and branched mycelium.

Discussion

962.	Assertion : It is poosbile that the asexual and vegetative stage of a fungi have been given one name ( and placed under deuteromycetes) and the sexual stage another ( and placed under another class). Reason : Once sexual stages of members of deuteromycetes were discovered they were often moved to phycomycetes and ascomycetes.A. If both assertion and reason are true and the reason is the correct explanation of the assertion.B. If both assertion and reason are true but reason is not the correct explanation of the assertion.C. If assertion is true but reason is false.D. If both assertion and reason are false.
Answer» Correct Answer - C Once sexual stages of members of deuteromyctes were discovered, they were often moved to ascomycetes and basidiomycetes.

Discussion

963.	Mycorrhiza are the the example ofA. amensalismB. antibioticsC. mutualismD. fungistasis
Answer» Correct Answer - C

Discussion

964.	Which of the following components provides sticky character to the bacterial cellA. Nuclear membraneB. Plasma membraneC. GlycocalyxD. Cell wall
Answer» Correct Answer - C

Discussion

965.	Which of the following are found in extreme saline conditionsA. EubacteriaB. CyanobacteriaC. MycobacteriaD. Archaebacteria
Answer» Correct Answer - D

Discussion

966.	Name a microbe used for statin production. How do statins lower blood cholesterol level ?
Answer» Monascus purpureus statins act by compectitively inhibiting the enzyme responsible for the synthesis of cholesterol.

Discussion

967.	Assign the position of the element having outer electronic configuration a.`ns^(2)np^(4)` for `n=3` b. `(n-1)d^(2)ns^2` for `n=4` and c. `(n-2) f^(7)(n-1)d^(1)ns^(2)` for `n=6`, in the periodic table.
Answer» (i) Since n = 3, the element belongs to the `3^(rd)` period. It is a p–block element since the last electron occupies the p–orbital. There are four electrons in the p–orbital. Thus, the corresponding group of the element = Number of s–block groups + number of d–block groups + number of p–electrons = 2 + 10 + 4 = 16 Therefore, the element belongs to the `3^(rd)` period and `16^(th)` group of the periodic table. Hence, the element is Sulphur. (ii) Since n = 4, the element belongs to the `4^(th)` period. It is a d–block element as d–orbitals are incompletely filled. There are 2 electrons in the d–orbital. Thus, the corresponding group of the element = Number of s–block groups + number of d–block groups = 2 + 2 = 4 Therefore, it is a `4^(th)` period and `4^(th)` group element. Hence, the element is Titanium. (iii) Since n = 6, the element is present in the `6^(th)` period. It is an f –block element as the last electron occupies the f–orbital. It belongs to group 3 of the periodic table since all f-block elements belong to group 3. Its electronic configuration is [Xe] `4f^(7) 5d^(1) 6s^(2)`. Thus, its atomic number is 54 + 7 + 2 + 1 = 64. Hence, the element is Gadolinium.

Discussion

968.	Amongst `H_2O, H_2S, H_2 Se` and `H_2 Te`, the one with the highest boiling point is :A. `H_(2)O` because of hydrogen bondingB. `H_(2)Te` because of higher molecular weightC. `H_(2)S` because of hydrogen boningD. `H_(2)Se` because of lower molecular weight
Answer» Correct Answer - A In hydrides of ground `16`, boiling point increases down the group because of increasing molecular mass. But water has an exceptionally high boiling point because it shows intermolecular hydrogen bonding. One `H_(2)O` molecule is bonded to four molecules of `H_(2)O`

Discussion

969.	`Ca^(2+)` has a smaller ionic radius than `K^(oplus)` because it has `"………" .
Answer» Correct Answer - Higher charge density `Ca^(2+)` has a smaller ionic radius than `K^(o+)` because it has higher charge density `(("charge")/("size") "ratio")`. In isoelectronic species, as the number of protons (atomic number) goes on increasing, size goes on decreasing due to stronger attraction on the electrons.

Discussion

970.	Arrange the following as stated: Increasing order of ionic size `N^(3-),Na^(oplus),F^(ɵ),O^(2-),Mg^(2+)`
Answer» Correct Answer - `Mg^(2+) lt Na lt F^(ɵ) lt O^(2-) lt N^(3-)` The increasing order of ionic sizes is `Mg^(2+) lt Na lt F^(ɵ) lt O^(2-) lt N^(3-)` All of these are isoelectronic ions. In isoelectronic species, as the number of protons (atomic number) goes on increasing, size goes on decreasing due to stronger attraction on the electrons.

Discussion

971.	Arrange the following ions in order of their decreasing ionic radii. `Li^(o+), K^(o+), Mg^(2+), Al^(3+)`
Answer» Correct Answer - `Al^(3+) lt Mg^(2+) lt Li^(o+) lt K^(o+)` `Al^(3+) lt Mg^(2+) lt Li^(o+) lt K^(o+)` `Al^(3+)` and `Mg^(2+)` are isoelectronic ions. In isoelectronic species, as the number of protons (atomic number) goes on increasing, size goes on decreasing due to stronger attraction on the electrons. `K^(o+)` is larger than `Li^(o+)` because on moving down the group, size decreaases.

Discussion

972.	Considering the elements `B, C, N` and `Si`, the correct order of their non-metallic character is ?A. `B gt C gt Si gt N gt F`B. `Si gt C gt B gt N gt F`C. `F gt N gt C gt B gt Si`D. `F gt N gt C gt Si gt B`
Answer» Correct Answer - C Non-metallic character decreases down the group `(darr)` and increases along the period `(rarr)`. Therefore, non-metallic character order is `\|{:(,F gt,N gt,C gt,B gt,Si),("Group",17,15,14,13,14),("Period",2nd,2nd,2nd,2nd,3rd):}\|`

Discussion

973.	The elements of group `1,2,13,14,15,16,17,18` are collectively calledA. Noble elementsB. Typical elementsC. Transition elementsD. Representative elements
Answer» Correct Answer - D `s`-and `p`-block elements are called representative elements.

Discussion

974.	The first ionisation energy is maximum forA. `Na`B. `Mg`C. `K`D. `Kr`
Answer» Correct Answer - D `IE_(1)` is maximum for `Kr` (inert gas) due to the full - filled `p`-orbitals.

Discussion

975.	The second ionisation potentials in electron volts of oxygen and fluorine atoms are respectively given byA. `35.1, 38.3`B. `38.3, 38.3`C. `38.3, 35.1`D. `35.1, 35.1`
Answer» Correct Answer - C `IE_(2)` of `O (38.3 eV) gt IE_(2)` of `F(35.1 eV)`.

Discussion

976.	In which group of organisms the cell walls form two thin overlapping shells which fit togetherA. Slime mouldsB. ChrysophytesC. EuglenoidsD. Dinoflagellates
Answer» Correct Answer - B

Discussion

977.	Which is the correct order of ionic sizes (At, No : `Ce=58,Sn=50,Yb=70` and `Lu=71`)?A. `CegtSngtYbgtLu`B. `SngtCegtLugtYb`C. `LugtYbgtSngtCe`D. `SngtYbgtCegtLu`
Answer» Correct Answer - B Correct order of ionic size is `SngtCegtLugtYb`.

Discussion

978.	The ionic conductance of the following cations in a given concentration is in the orderA. `Li^(+)lt Na^(+) gt k^(+)ltRb^(+)`B. `Li^(+) gt Na^(+) gt K^(+) gt Rb^(+)`C. `Li^(+) lt Na^(+) gt K^(+) gt Rb^(+)`D. `Li=Na^(+) lt K^(+) lt Rb^(+)`
Answer» Correct Answer - A With the increase in size of cation the size of the hydrated ion decrease hence ionic conductance increase.

Discussion

979.	Metallic radius is usually not defined for____elements.A. `f`-blockB. `d-`blockC. `s-`blockD. `p`-block
Answer» Correct Answer - D Metallic radius is used to describe the size of metal atoms. The elements of `s-,p-`, and `f`-block elements are all metals. Metallic radius, measured for the metallic elements, is half-distance between the nuclei of two neighboring atoms (actually metal cores) in the soild metal.

Discussion

980.	Which of the following elements is the least electronegative?A. `S`B. `Cl`C. `Br`D. `Se`
Answer» Correct Answer - D For the respesentative elements, electro0negativity values ussually increase from left to right across periods (because of decrease of atomic size on account of increase of `Z_(eff))` and decrease from top to bottom within groups (because of increase of atomic size on account of increase in the number of shells). Thus, the order of increasing electronegativity is `Se lt S lt Br lt CI` `{:(2.4,2.5,2.8,3.0,):}`

Discussion

981.	Which of the noble gases has the maximum positive `Delta_(eg)H`?A. `He`B. `Ne`C. `Ar`D. `Kr`
Answer» Correct Answer - B `Delta_(eg)H` becomes less and less positive from `Ne` onwards on account of increase of atomic size. Unusulaly low positive `Delta_(eg)H` for `He` is related to its very small size which leads to relatively greater attraction towards the nucleus. The correct order of decreasing positive `Delta_(eg)H` is `Negt Argt Kr gt Xegt Rn gt He`

Discussion

982.	Which of the following elements has negative `Delta_(eg)H`?A. `N`B. Alkaline earth metalC. Noble gasD. `P`
Answer» Correct Answer - B In spite of stable electron configuration lerge outer shell which reduces interelectron repulsion.

Discussion

983.	Which of the group `16` elements has the least negative `Delta_(eg)H`?A. `O`B. `S`C. `Se`D. `Te`
Answer» Correct Answer - A The correct order of decreaing negative `Delta_(eg)H` is: `Sgt Se gt Te gt O`. Oxygen has the least negative `Delta_(eg)H` on account of maximum `e^(-)-e^(-)` repulsion.

Discussion

984.	Which of the following elements has positive `Delta_(eg)H`? (i) `Mn` (ii) `Zn` (iii) `Cd` (iv) `Hg`A. `(i),(ii)`B. `(i),(ii),(iii)`C. `(i),(ii),(iii),(iv)`D. `(ii),(iii),(iv)`
Answer» Correct Answer - C All of the elements have stable electron configuration in the form of half-full or completely full subshells.

Discussion

985.	IUPAC name of A. bicyclo-[3,1,1]-octane-2-oic acidB. bicyclo-[3,2,1]-octane-1-carboxylic acidC. bicyclo-[3,2,1]-octane-8-oic acidD. none of the above
Answer» Correct Answer - D

Discussion

986.	Number of `1^(@),2^(@)` and `3^(@)` hydrogen in isooctane is:A. 9,8,1B. 12,5,1C. 15,2,1D. none of these
Answer» Correct Answer - C

Discussion

987.	IUPAC name of A. 5-ethenylcyclopenta-1,3-dieneB. 3-ethenylcyclopenta-1-,4-dieneC. 1-ethenylcyclopenta-2,4-dieneD. 2-ethenylcyclopenta-1,3-diene
Answer» Correct Answer - A

Discussion

988.	Which of the following are homoguces ?A. `CH_(3)CH_(2)-NH_(2)` and `CH_(3)CH_(2)NH-CH_(3)`B. `CH_(3)-OH` and `CH_(3)CH_(2)CH_(2)CH_(2)overset(OH)overset(\|)(CH_(2))`C. D. `CH_(3)COOH` and `CH_(3)-COOCH_(3)`
Answer» Correct Answer - B

Discussion

989.	How is ozone prepared? How does it react with the following? (i) PbS (ii) KI (iii) Hg (iv) Ag
Answer» Preparation of Ozone : A slow dry stream of oxygen under silent electric discharge to form ozone (about 10%). The product obtained is known as ozonised oxygen. 3O₂ → 2O₃ ∆H° = 142kJ/mole → The formation of ozone is an endothermic reaction. → It is necessary to use silent electric discharge in the preparation of O₃ to prevent its de- composition (i) Reaction with PbS : Black lead sulphide oxidised to white lead sulphate in presence of ozone. PbS + 4O₃ → PbSO₄+ 4O₂ (ii) Reaction with KI : Moist KI is oxidised to Iodine in presence of ozone. 2KI + H₂O + O₃ → 2KOH + I₂ + O₂ (iii) Reaction with Hg : Mercury loses it's lustreness, meniscus and consequently sticks to the walls of glass vessel when it reacts with ozone. This phenomenon is called tailing of mercury. 2Hg + O₃ → Hg₂O + O₂ It is removed by shaking it with water which dissolves Hg₂O. (iv)Reaction with Ag : Ag metal oxidised to Ag₂O (Ag metal is tarnished). 2Ag + O₃ → Ag₂O + O₂

989.

How is ozone prepared? How does it react with the following? (i) PbS (ii) KI (iii) Hg (iv) Ag

Answer»

Preparation of Ozone :

A slow dry stream of oxygen under silent electric discharge to form ozone (about 10%). The product obtained is known as ozonised oxygen.

3O₂ → 2O₃ ∆H° = 142kJ/mole

→ The formation of ozone is an endothermic reaction.

→ It is necessary to use silent electric discharge in the preparation of O₃ to prevent its de- composition

(i) Reaction with PbS : Black lead sulphide oxidised to white lead sulphate in presence of ozone.

PbS + 4O₃ → PbSO₄+ 4O₂

(ii) Reaction with KI : Moist KI is oxidised to Iodine in presence of ozone.

2KI + H₂O + O₃ → 2KOH + I₂ + O₂

(iii) Reaction with Hg : Mercury loses it's lustreness, meniscus and consequently sticks to the walls of glass vessel when it reacts with ozone. This phenomenon is called tailing of mercury.

2Hg + O₃ → Hg₂O + O₂

It is removed by shaking it with water which dissolves Hg₂O.

(iv)Reaction with Ag : Ag metal oxidised to Ag₂O (Ag metal is tarnished).

2Ag + O₃ → Ag₂O + O₂

Discussion

990.	Which form of reproduction is correctly matched ?A. Euglena `to` transverse binary fissionB. Paramecium `to` longitudinal binary fissionC. Amoeba `to` multiple fissionD. Plasmodium ` to ` binary fission
Answer» Correct Answer - C

Discussion

991.	In the vast marine ecosystem, certain sea develop red colouration. This red colour is due to the presence of large population of which one of the following organisms ?A. Trichodesmium erythraeumB. PhysariumC. DinoflagellatesD. Diatoms and members of red algae
Answer» Correct Answer - A

Discussion

992.	I. Unicellular. Colonial, filamentous, marine or terrestrial forms II. The colonial , filamentous, marine or terrestrial forms III. Some can fix atmospheric nitrogen in specialised cells called heterocysts IV. They often form blooms in water bodies. these above characters are seen inA. ArchaebacteriaB. CyanobacteriaC. ChrysophytesD. Dinoflagellates
Answer» Correct Answer - B I. Unicellular, colonial, filamentous, marine or terrestrial forms. II. The colonies are surrounded by a gelatinous sheath. III. Some can fix atmospheric nitrogen in specialized cells called heterocysts. IV. They often form blooms in water bodies. These above characters are seen in Cyanobacteria.

Discussion

993.	Name the three major groups of protists.
Answer» Protistan algae, slime moulds and protozoan protists.

Discussion

994.	Mycoplasmas are classified under which of the following kingdoms?A. MoneraB. ProtistaC. FungiD. Plantae
Answer» Correct Answer - A

Discussion

995.	Which of the following combinations of characters is true for slime moulds?A. Parasitic, plasmodium without walls, spores dispersed by air currentsB. Saprophytic, plasmodium with walls, spores dipersed by waterC. Parasitic, plasmodium without walls, spores dispersed by waterD. Saprophytic, plasmodium without walls, spores dispersed by air currents.
Answer» Correct Answer - D Slime moulds are saprophytic protists having plasmodium as a free-living thalloid body. Plasmodium is wall less mass of multinucleate protoplasm covered by slime. During unfavourable conditions, the plasmodium differentiates and forms fruiting bodies bearing spores at their tips. These spores are dispersed by air currents.

Discussion

996.	Mode of reproduction exhibited by the protists isA. Asexual reproductionB. Sexual reproductionC. Both asexual and sexual reproductionD. A sort of sexual reproduction
Answer» Correct Answer - C Mode of reproduction exhibited by the protists is both asexual and sexual reproduction.

Discussion

997.	____ is the most common method of reproduction in bacteria.A. Binary fissionB. Endospore formationC. ConjugationD. Sexual reproduction
Answer» Correct Answer - A Reproduction in bacteria occurs by three methods - binary fission, sporulation and sexual reproduction. Binary fission is the most common method of bacterial multiplication under favourable conditions, in which a mature bacterium divides into two equal daughters cells.

Discussion

998.	The marine animal which exhibits the characteristic of bioluminescence isA. NoctilucaB. TrypanosomaC. LeishmaniaD. Volvox
Answer» Correct Answer - A The marine animal which exhibits the characteristic of bioluminescence is Noctiluca.

Discussion

999.	Protists are primarily ___ in nature.A. ThermophilicB. AquaticC. TerrestrialD. Parasitic
Answer» Correct Answer - B Protists are primarily aquatic in nature.

Discussion

1000.	Select the pair consiss of plant or animal bacterial diseases.A. Cholera and typhoidB. Citrus canker and crown gallC. Malaria and dengueD. Both (a) and (b)
Answer» Correct Answer - D Pathogen of cholera is Vibrio cholerae bacterium. Cholera is transmitted by contaminated water. Typhoic or eneric fever spreads through contaminated water in which bacterium Salmonella typhi is present. Citrus canker and crown gall are bacterial diseases of plants caused by Xanthomonas citri and Anrobacterium tumefaciens, respectively.

Discussion

Explore topic-wise InterviewSolutions in .

Which of the following exhibits only +3 oxidation state?A. `U`B. `Th`C. `Pa`D. `Ac`

Which of the following lanthanoids ions is diamagnetic?A. `Sm^(2+)`B. `Eu^(2+)`C. `Ce^(2+)`D. `Yb^(2+)`

Among the following series of transition metals ions, the one where all metal ions have `3d^(2)` electronic configuration is:A. `Ti^(3+),V^(2+),Cr^(3+),Mn^(4+)`B. `Ti^(+),V^(4+),Cr^(6+),Mn^(7+)`C. `Ti^(4+),V^(3+),Cr^(2+),Mn^(3+)`D. `Ti^(2+),V^(3+),Cr^(4+),Mn^(5+)`

Among `K,Ca,Fe` and `Zn` the element which can form more than one binary compound with chlorine isA. `Fe`B. `Zn`C. `K`D. `Ca`

Each group of the modern periodic table consists of a number of elements having the similar electronic configuration of the_____shell.A. pendultimateB. valenceC. outermostD. antepenulimate

On what basis the fungi were earlier included in the plant kingdom ?

Give reasons why fungi should not be included in Plant Kingdom.

Give a comparative account of the classes of Kingdom Fungi under the following: (i) Mode of nutrition (ii) Mode of reproduction

Which of the following classes of kingdom Fungi are characterised by the presence of coenocytic, multinucleate and branched mycelium?A. BasidiomycetesB. PhycomycetesC. AscomycetesD. Deuteromycetes

Mycorrhiza are the the example ofA. amensalismB. antibioticsC. mutualismD. fungistasis

Which of the following components provides sticky character to the bacterial cellA. Nuclear membraneB. Plasma membraneC. GlycocalyxD. Cell wall

Which of the following are found in extreme saline conditionsA. EubacteriaB. CyanobacteriaC. MycobacteriaD. Archaebacteria

Name a microbe used for statin production. How do statins lower blood cholesterol level ?

Assign the position of the element having outer electronic configuration a.`ns^(2)np^(4)` for `n=3` b. `(n-1)d^(2)ns^2` for `n=4` and c. `(n-2) f^(7)(n-1)d^(1)ns^(2)` for `n=6`, in the periodic table.

Amongst `H_2O, H_2S, H_2 Se` and `H_2 Te`, the one with the highest boiling point is :A. `H_(2)O` because of hydrogen bondingB. `H_(2)Te` because of higher molecular weightC. `H_(2)S` because of hydrogen boningD. `H_(2)Se` because of lower molecular weight

`Ca^(2+)` has a smaller ionic radius than `K^(oplus)` because it has `"………" .

Arrange the following as stated: Increasing order of ionic size `N^(3-),Na^(oplus),F^(ɵ),O^(2-),Mg^(2+)`

Arrange the following ions in order of their decreasing ionic radii. `Li^(o+), K^(o+), Mg^(2+), Al^(3+)`

Considering the elements `B, C, N` and `Si`, the correct order of their non-metallic character is ?A. `B gt C gt Si gt N gt F`B. `Si gt C gt B gt N gt F`C. `F gt N gt C gt B gt Si`D. `F gt N gt C gt Si gt B`

The elements of group `1,2,13,14,15,16,17,18` are collectively calledA. Noble elementsB. Typical elementsC. Transition elementsD. Representative elements

The first ionisation energy is maximum forA. `Na`B. `Mg`C. `K`D. `Kr`

The second ionisation potentials in electron volts of oxygen and fluorine atoms are respectively given byA. `35.1, 38.3`B. `38.3, 38.3`C. `38.3, 35.1`D. `35.1, 35.1`

In which group of organisms the cell walls form two thin overlapping shells which fit togetherA. Slime mouldsB. ChrysophytesC. EuglenoidsD. Dinoflagellates

Which is the correct order of ionic sizes (At, No : `Ce=58,Sn=50,Yb=70` and `Lu=71`)?A. `CegtSngtYbgtLu`B. `SngtCegtLugtYb`C. `LugtYbgtSngtCe`D. `SngtYbgtCegtLu`

The ionic conductance of the following cations in a given concentration is in the orderA. `Li^(+)lt Na^(+) gt k^(+)ltRb^(+)`B. `Li^(+) gt Na^(+) gt K^(+) gt Rb^(+)`C. `Li^(+) lt Na^(+) gt K^(+) gt Rb^(+)`D. `Li=Na^(+) lt K^(+) lt Rb^(+)`

Metallic radius is usually not defined for____elements.A. `f`-blockB. `d-`blockC. `s-`blockD. `p`-block

Which of the following elements is the least electronegative?A. `S`B. `Cl`C. `Br`D. `Se`

Which of the noble gases has the maximum positive `Delta_(eg)H`?A. `He`B. `Ne`C. `Ar`D. `Kr`

Which of the following elements has negative `Delta_(eg)H`?A. `N`B. Alkaline earth metalC. Noble gasD. `P`

Which of the group `16` elements has the least negative `Delta_(eg)H`?A. `O`B. `S`C. `Se`D. `Te`

Which of the following elements has positive `Delta_(eg)H`? (i) `Mn` (ii) `Zn` (iii) `Cd` (iv) `Hg`A. `(i),(ii)`B. `(i),(ii),(iii)`C. `(i),(ii),(iii),(iv)`D. `(ii),(iii),(iv)`

IUPAC name of A. bicyclo-[3,1,1]-octane-2-oic acidB. bicyclo-[3,2,1]-octane-1-carboxylic acidC. bicyclo-[3,2,1]-octane-8-oic acidD. none of the above

Number of `1^(@),2^(@)` and `3^(@)` hydrogen in isooctane is:A. 9,8,1B. 12,5,1C. 15,2,1D. none of these

IUPAC name of A. 5-ethenylcyclopenta-1,3-dieneB. 3-ethenylcyclopenta-1-,4-dieneC. 1-ethenylcyclopenta-2,4-dieneD. 2-ethenylcyclopenta-1,3-diene

Which of the following are homoguces ?A. `CH_(3)CH_(2)-NH_(2)` and `CH_(3)CH_(2)NH-CH_(3)`B. `CH_(3)-OH` and `CH_(3)CH_(2)CH_(2)CH_(2)overset(OH)overset(|)(CH_(2))`C. D. `CH_(3)COOH` and `CH_(3)-COOCH_(3)`

How is ozone prepared? How does it react with the following? (i) PbS (ii) KI (iii) Hg (iv) Ag

Which form of reproduction is correctly matched ?A. Euglena `to` transverse binary fissionB. Paramecium `to` longitudinal binary fissionC. Amoeba `to` multiple fissionD. Plasmodium ` to ` binary fission

In the vast marine ecosystem, certain sea develop red colouration. This red colour is due to the presence of large population of which one of the following organisms ?A. Trichodesmium erythraeumB. PhysariumC. DinoflagellatesD. Diatoms and members of red algae

Name the three major groups of protists.

Mycoplasmas are classified under which of the following kingdoms?A. MoneraB. ProtistaC. FungiD. Plantae

Mode of reproduction exhibited by the protists isA. Asexual reproductionB. Sexual reproductionC. Both asexual and sexual reproductionD. A sort of sexual reproduction

____ is the most common method of reproduction in bacteria.A. Binary fissionB. Endospore formationC. ConjugationD. Sexual reproduction

The marine animal which exhibits the characteristic of bioluminescence isA. NoctilucaB. TrypanosomaC. LeishmaniaD. Volvox

Protists are primarily ___ in nature.A. ThermophilicB. AquaticC. TerrestrialD. Parasitic

Select the pair consiss of plant or animal bacterial diseases.A. Cholera and typhoidB. Citrus canker and crown gallC. Malaria and dengueD. Both (a) and (b)