94420 + Interview Questions in Chemistry in Class 12

1.	In a closed flask of 5 litres, 1.0 g of H_(2) is heated from 300 to 600 K. Which statement is/are correct?
Answer» Pressure of the GAS increases The rate of COLLISION increases The number of MOLES of gas increases The energy of GASEOUS molecules increases Answer :A::B::D

Discussion

2.	If the initial concentration of reactants in a certain reaction is doubled the half life period of the reaction doubles . The order of the reaction is :
Answer» ZERO FIRST Second Third ANSWER :A

Discussion

3.	In a closed insulated container, a liquid is stirred with a paddle to increase the temperature. Which of the following is true ?
Answer» `Delta U = W NE 0, Q = 0` `Delta U = w, q ne 0` `Delta U = 0, w = q ne 0` `w = 0, Delta = q ne 0` Answer :A

Discussion

4.	In the initial cocnentration is reduced to 1/4th of the initial value of a zero order reaction the half life of the reaction
Answer» REMAIN CONSTANT BECOMES 1/4 th becomes double Becomes fourfold Answer :B

Discussion

5.	In a closed containerr, a liquid is stirred with a paddle to increse the temperature. Which of the following is true?
Answer» `DeltaE=W ne0,q=0` `DeltaE=W=qne0` `DeltaE=0,W=qne0` `W=0,DeltaE=qne0` Solution :`DeltaE=q+W` q=0 (`because` TEMPERATURE is to be increased, no heat should ENTER or leave the SYSTEM) `DeltaE=q+W=0+W` or `DeltaE=W` `therefore W ne 0,q=0`.

Discussion

6.	If the hydrogen ion concentration of a given solution is 5.5 xx 10^(-3) " mol litre"^(-1), the pH of the solution will be
Answer» 2.26 3.4 3.75 2.76 Solution :`[H^(+)] = 5.5 xx 10^(-3)` mole/litre `pH = -LOG [H^(+)] , pH = -log [ 5.5 xx 10^(-3)] , pH = 2.26`.

Discussion

7.	In a closed insulated container, a liquid is stirred with a paddle to increase its temperature. In this process, which of the following is true
Answer» `DeltaE=W=Q=0` `DeltaE ne0,Q=W=0` `DeltaE=W NE 0, Q=0` `DeltaE = Qne0, W=0` SOLUTION :As the system is closed and INSULATED no heat ENTER or leave the system, i.e. q = 0 , `thereforeDeltaE = Q+W=W`.

Discussion

8.	In a closed container of capacity V with N_(2)(g) and wate vapour at 298 k, the pressure observed is 1.8 atm. If the volume is squeezed to V/3, then the preesue of the container is….., if aq. Tension of H_(2)O(g) is 0.2 atm at 298 K.
Answer» Solution :5 atm WATER VAPOURS do not FOLLOW Boyle.s LAW.

Discussion

9.	If the hydrogen ion concentration of a given solution is 5.5 xx 10^-3 M. Find the pH of the solution.
Answer» 2.26 3.4 3.75 4.76 Answer :A

Discussion

10.	In a closed container NO_(2) gas is getting dimerised into N_(2)O_(4) gas with first order kinetics. Pressure after 10 hours of reaction is 5 atm and pressure after completion of reaction is 4atm. What is half life in hours?
Answer» <P> SOLUTION :`2NO_(2(g))hArrN_(2)O_(4(g))` So `P_(0)=8` atm `(P_(0)-y/2)=5` `(P_(0)-y)=(8-6)=2` atm` Kxxt=2.303xxlog((P_(0))/(Pt))` `0.693/((t_(1//2)))xx10=2.303xxlog(8/2),(0.3010xx10)/((t_(1/2)))=2xxlog2,(0.3010x10)/((t_(1/2)))=2xx0.3010`, `(t_(1/2))=10/2=5,t_(1/2)=5`

Discussion

11.	If the highest oxidation states shown by any Lanthanide and any Actinide are +X and+Y, the sum of X+Y is euqal to?
Answer» ANSWER :`11.00`

Discussion

12.	if the heat of neutralisation for a strong acid- base reaction is -57.1 kJ, would be the heat released when 350 cm^(3)of 0.20 M ofa dibasic strong acid is mixed with 650 cm^(3) of 0.10 M monoacidic base ?
Answer» 57.1 kJ 3.71 kJ `-57.1 kJ` 0.317 kJ Solution :millimoles of dibasic strong ACID ` M XX V=0.20xx350=70 MMOL` Amount of `H^(+)` IONS in the acid = `2xx70=140 mmol` SIMILARLY, amount of `OH^(-)`ions in the acid `0.10xx650xx =65 mmol` [ Here, `OH^(-)` is the limiting reactant] `65 xx10^(-3)` mole of `OH^(-)` ions will produce `=57.1xx65xx10^(-3)=3.71kJ`

Discussion

13.	If the heat of formation of CO_(2) is -393 kJ. The amount of heat evolved in the formation of 0.156 kg of CO_(2) is
Answer» `-1357.9`kJ `-1275.9` kJ `-1572.0` kJ `-1165.5` kJ Solution :Heat of formation of a SUBSTANCE is the heat exchanged when one MOLE of that substance is FORMED by its constituent elements. `because` Heat evolved when 1 mole (44g) `CO_(2)` is formed `=(393xx156)/(44)` `therefore DELTAH` for the process = 1572 kJ =-1572.0 kJ`.

Discussion

14.	If the heat of combustion of carbon monoxide at constant volume and at 17^(@)C is - 283.3 kJ, then its heat of combustion at constant pressure (R=8.314 J degree^(-1) mol^(-1)
Answer» `- 284.5` KJ 284.5 kJ 384.5 kJ `- 384.5 kJ` Solution :`CO_((g))+(1)/(2)O_(2(g))rarrCO_(2(g)), Deltan=1-1(1)/(2)=-(1)/(2)` `DeltaH=DeltaE+DeltanRT` `DeltaH=-283.3-(1)/(2)XX(8.314)/(1000)xx290=-284.5 kJ`

Discussion

15.	In a close packing of atoms A of radius r_(a), the radius of atom B that can be fitted in tetrahedral void is
Answer» `0.225 r_(a)` `0.155 r_(a)` `0.414 r_(a)` `0.732r_(a)` ANSWER :A

Discussion

16.	If the half-life period of a first order reaction is 138.6 minutes, then the value of decay constant for the reaction will be
Answer» `5 "miniute"^(-1)` `0.5 "MINUTE"^(-1)` `0.05 "minute"^(-1)` `0.005 "minute"^(-1)` Solution :`K = (0.693)/(t_(1//2)) = (0.693)/(138.6 "MIN") = 0.005 "min"^(-1)`

Discussion

17.	In a close-packed structure, if r is the radius of the spherical void and R is the radius of the spheres forming voids, the critical r/R value for the tetrahedral void is equal to
Answer» 0.155 0.225 0.414 0.732 Answer :B

Discussion

18.	If the half-life of an isotope X is 10 years, its decay constant is
Answer» `6.932 YR^(-1)` `0.6932 yr^(-1)` `0.06932 yr^(-1)` `0.006932 yr^(-1)` SOLUTION :`K = (0.693)/(t_(1//2)), K = (0.693)/(10) == 0.0693 yr^(-1)`

Discussion

19.	In a close packed structure of mixed oxides , the lattice is composed of oxide ions , one eighth of the tetrahedrai voids are occupied by divalent cations ( A ) while half of the octahedral voids are occupied by trivalent cations ( B ) . What is the formula of the oxide ?
Answer» `A_2B_3O` `A_4B_2O_3` `AB_2O_4` `A_3B_2O_2` ANSWER :C

Discussion

20.	If the half life period for a reaction in A is 100 min . How long will it take [A] to reach 25 % of its initial concentration ?
Answer» 50 MIN 250 min 200 min 500 min Solution :( C) K `= (0.693)/(100) = 6.93 xx10^(-3)` ` t= (2.303)/(6.93xx10^(-3)) "LOG" ([A]_(0))/(0.25[A]_(0))` `= (2.303)/(6.93xx10^(-3))"log"4` `= (2.303)/(6.93xx10^(-3))xx0.6020` =200 min

Discussion

21.	In a close packed structure of mixed oxide, the lattice is composed of O^(2-) ions. One eighth of tetrahedral voids are occupied by divalent cations A^(2+) and one half of octahedral voids by trivalent cations B^(3+) What is the formula of oxide ?
Answer» SOLUTION :`AB_(2)O_(4)`

Discussion

22.	If the half-life of a radioisotope is 4 days, then how long would it take for 75% disitegration of the sample?
Answer» 8 days 10 days 12 days 14 days Solution :`t_(1//2) = 4 "days", lambda = (0.693)/4 "days"^(-1)` `N_0 = 100, N_t = 25` Now `t = (2.303)/(lambda) log (N_0)/(N_t)` `implies t = (2.303 xx 4)/(0.693) log (100)/(25) = (18.424)/(0.693) xx 0.301 = 8 ` days It WOULD TAKE 8 days for 75% distintegration of the SAMPLE.

Discussion

23.	In a close packed centred cubic lattice of potassium the corrcet relation between the atomic radius (r)of potassium and the edge length (a) of the cube is
Answer» `R=a/(sqrt(2))` `r=a/(sqrt(3))` `r=(sqrt(3))/2a` `r=(sqrt(3))/4a` SOLUTION :For BCC `4r=sqrt(3)aimpliesr=(sqrt(3))/4a`

Discussion

24.	If the half cell reactions are given as (i) Fe_((aq))^(2+)+2etoFe_((s)),E^(o)=0.44V (ii) 2H_((aq))^(+)+(1)/(2)O_(2(g))+2etoH_(2)O_((l)),E^(o)=+1.23V The E^(o) for the reaction Fe_((s))+2H^(+)+(1)/(2)O_(2(g))toFe_((aq))^(2+)+H_(2)O_((l))
Answer» `+1.67V` `-1.67V` `+0.79V` `-0.79V` Solution :Subtracting EQUATION (i) from (II) we will get equation (iii) `Fe_((s))+2H^(+)+(1)/(2)O_(2)toFe_((aq))^(2+)+H_(2)O_((l))`. . .(iii) So, `E^(o)=E_(2)^(o)--E_(1)^(0)` `=+1.23-(-0.44)=+1.6V`

Discussion

25.	In a close packed lattice containing 'n' particles, the number of tetrahedral and octahedral voids respectively
Answer» N and 2N n and n 2n and n 2n and n/2 Answer :C

Discussion

26.	In a close packed arrangement of N spheres, how many i) tetrahedral and (ii) octahedral sites are present ?
Answer» SOLUTION :(i) TETRAHEDRAL SITES = 2N (ii) OCTAHEDRAL sites = N.

Discussion

27.	If the half life of a first order reaction is 60 min, the approximate time in min, required to complete 90% of the reaction is (log2=0.3)
Answer» `200` `240` `50` `100` ANSWER :A

Discussion

28.	In a classroom, the teacher has explained the quantitative aspects of electrolysis by stating the Faraday's laws of electrolysis. Calculate the quantity of electricity required to deposit 0.09 g of aluminium during the following electrode reaction: Al^3 + 3e^(-) to Al ( Al=27u)
Answer» Solution :Quantity of electricity required to deposit 27 G (1 mole ) of Al = 3F = `3xx96500` coulombs `THEREFORE .Quantity of electricity required to deposit (0.09g of Al `3xx96500xx0.09)/27`=965 coulombs

Discussion

29.	If the half cell reaction A+e^(-)toA^(-) has a large negative reduction potential,it follows that
Answer» A is readily reduced A is readily oxidised `A^(-)` is readily reduced `A^(-)` is readily oxidised Solution :Since `E_(A//A^(-))^(@)` has LARGE NEGATIVE VALUE, the tendency of A to be reduced to `A^(-)` is very SMALL. In other words tendency of `A^-` to be oxidized to A is very large.

Discussion

30.	In a close pack array of n spheres, the number of tetrahedral holes are :
Answer» 4N N/2 2N N ANSWER :C

Discussion

31.	If the half cell reaction A to e^(-) to A^(-) has a larger negative potential , it follows that :
Answer» A is not READILY redused A is readily oxidised `A^(-)` is readily REDUCED `A^(-)` is readily oxidised SOLUTION :`A + E^(-) to A^(-) , `A is not readily reduced , A is readily oxidised

Discussion

32.	If the half-cell reaction A +e rarr A^(-) has a large negative reduction potential, it follows that
Answer» `A^(-)` is READILY oxidized A is readily oxidised `A^(-)` is readily REDUCED A is readily reduced ANSWER :A

Discussion

33.	If the half cell reaction A +e rarr A^- has a large negative reduction potential, it follows that :
Answer» A is READILY REDUCED A is readily oxidised `A^-` is readily reduced `A^-` is readily oxidised Answer :D

Discussion

34.	If the greenhouse effect or global warming remains unchecked, it alter :
Answer» SEA levels Temperature Rainfall All of these Answer :D

Discussion

35.	In a classroom discussion about order and moleculrity of a reaction,Ramu argued that ''there are reactions which appear to be of higher order but actually follows first order kinetics''How far is his statement true? Give your opinion in this regard. Justify your answer using suitable example.
Answer» Solution :It is a true statement. For example, hydrolysis of ethyl ACETATE in presence of acid APPEARS to be seconds order, but actually the order of the REACTION is one. Such reaction are CALLED pseudo FIRST order reaction.`CH_3COOC_2H_5+H_2O overset(Acid)oversettolarrCH_3COOH+C_2H_5OH`

Discussion

36.	State the Faraday's laws of electrolysis
Answer» Solution :I law: The amount of a substances deposited or liberated during dectrolysis is directly proportional to the quantity of electricity FLOWING through the electrolyte. II law :If the same quantity of electricity is PASSED through different ELECTROLYTES the amount of SUBSTANCE formed are directly proportional to their equivalent WEIGHT.

Discussion

37.	If the gold number of potato starch is 25, how many grams of it is required to prevent coagulating of 100mL of gold sol on adding 10mL of 10% NaCl solution?
Answer» 0.3 0.5 0.25 0.4 Answer :C

Discussion

38.	In a classroom, the teacher has explained the quantitative aspects of electrolysis by stating the Faraday's laws of electrolysis.Explain the term electrochemical equivalent
Answer» Solution : It is the quantity of a substance formed at the electrode, when ONE ampere CURRENT is PASSED through an ELECTROLYTE for one second.

Discussion

39.	If the given four electronic configurations (i) n = 4, l = 1 (ii) n = 4, I= 0 (iii) n = 3, l = 2 (iv) n = 3, I= 1 are arranged in order of increasing energy, then the order will be
Answer» (iv)lt (ii)lt (iii) lt (i) (ii)lt (iv)lt (i) lt (iii) (i) lt (iii) lt (ii) lt (iv) (iii) lt (i) lt (iv) lt (ii) SOLUTION :(i) n = 4, l = 1 `rArr` 4p-orbital (ii) n = 4, l = 0 `rArr` 4s-orbital (iii) n = 3, l = 2 `rArr` 3D-orbital (iv) n = 3, I= I `rArr` 3P-orbital Increasing order of energy as PER (n +l)rule : 3p < 4s < 3d < 4p (iv) (ii) (iii) (i)

Discussion

40.	In a class room, a teacher was teaching about batteries in the chapter of 'electrochemistry' to 12th class. As the use of batteries is very common now a days for invertors and cellphones, students were very curious to know which battery they should use for their invertors at home and for their cellphones as a number of cheap as well as costly batteries are available in the market. the teacher advised them that they should use those batteries which do not cause any pollution or health hazard though these may be a little constlier. thus, he suggested the use of cadmium battery in place of lead storage battery for invertor and lithium ion battery in place of Ni-Cd battery low celphone. After reading the above paragraph, answer the followng questions: (i) What values are expressed by the teacher? (ii) How is lead storage battery harmful in the long run? (iii) How is Ni-Cd battery harmful? What are other advantages of using Li-Ion battery over Ni-Cd battery?
Answer» Solution :(i) The teacher has expressed concern that we should not use those materials which cause health hazard or pollution in the ATMOSPHERE. (ii) Lead is poisonous. It has harmful effects on health as well as environment. (iii). Cd is TOXIC heavy metal and requires special care for disposal. other adavantages of Li-ion battery are: (a) It has a voltage of 3.6-3.7V whereas Ni-Cd battery has 1.2 V (B) It does not need periodic discharge whereas Ni-Cd battery is charged only after it is fully discharged. (C) Li-ion batteries do not LOSE their charge even after months of storage whereas Ni-Cd batteries lose 1-5% of their charge per day.

Discussion

41.	If the geometry of [PtCl_(4)]^(2-) is square planar, which orbitals of Pt are involved in the bonding ?
Answer» SOLUTION :`dsp^(2)` HYBRIDISATION INVOLVING 5d, 6s and 6P ORBITALS.

Discussion

42.	In a chemical reaction K_(2)Cr_(2)O_(7)+xH_(2)SO_(4)+ySO_(2)toK_(2)SO_(4)+Cr_(2)(CO_(4))_(3)+zH_(2)O the values of x,y,z are
Answer» `1,3,1` `4,1,4` `3,2,3` `2,1,2` SOLUTION :BASED on BALANCING.

Discussion

43.	If the freezing point of a 0.01 molal aqueous solution of a cobalt(III) chloride-ammonia complex (which behaves as a strong electrolytes) is -0.0558^(@)C, the number of chloride(s) in the coordination sphere of the complex is [K_(f) of water =1.86 Kkgmol^(-1)]
Answer» SOLUTION :`DELTA T_(f)=K_(f)xx ixx m rArr 0.0558=1.86xx ixx0.01` i=3 Given COMPLEX BEHAVES as a STRONG electrolyte `alpha = 100%` n = 3(no. of particles given by complex) `therefore` complex is `[Co(NH_(3))_(5)Cl]Cl_(2)` no. of `Cl^(-)` ions in the co-ordination sphere of the complex = 1 `Delta T_(f)=K_(f)xx ixx m` `0.0558=1.86xx ixx0.01` i = 3

Discussion

44.	In a chemical reaction triangleH=150kJ and triangleS= 100JK^-1 at 300K. The triangleG for the reaction is :
Answer» Zero 300 kJ 330kJ 120 kJ Answer :D

Discussion

45.	If the freezing point of 0.01 molal aqueous solution of cobalt (III) chloride-ammonia complex (which behaves as a strong electrolyte) is -0.0558^(@)C, the number of chloride(s) in the coordination sphere of the complex is (K_(f)" of water "="1.86 K kg mol"^(-1))
Answer» Solution :`DeltaT_(f)=iK_(f)m` Given `m=0.01 " molal, "T_(f)=-0.0558^(@)C`, `K_(f)="1.86 K kg mol"^(-1)` `DeltaT_(f)=T_(f)^(@)-T_(f)=0-(-0.0558)=0.0558^(@)` `i=(DeltaT_(f))/(K_(f)m)=(0.0588)/(1.86xx0.01)=3` As 3 ions are produced on dissociation of the complex, the molecular FORMULA of the complex is `[Co(NH_(3))_(5)Cl]Cl_(2)`. Thus, only one chloride ion is present in the coordination sphere.

Discussion

46.	In a chemical reaction, the rate constant for the backward reaction is 7.5xx10^(-4) and the equilibrium constant is 1.5.The rate constant for the forward reaction is :
Answer» `5xx10^(-4)` `2xx10^(-3)` `1.125xx10^(-3)` `9.0xx10^(-4)` SOLUTION :`K=(k_(F))/(k_(b))` or `k_(f)=K xx k_(b)` `=1.5xx7.5xx10^(-4)` `=1.125xx10^(-3)`

Discussion

47.	If the freezing point of a 0.01 molal aqueous solution of a cobalt (III) chloride-ammonia complex (which behaves as a strong electrolyte) is -0.0558^(@)C, the number of chloride (s) in the coordination sphere of the complex if [K_(f) of water =1.86 K kg mol^(-1)]
Answer» Solution :`DeltaT_(F)=ixxK_(f)xxm` `i=(DeltaT_(f))/(K_(f)xxm)=((0.0558K))/((1.86 KM^(-1))xx(0.01m))=3` The value of I indicates that in aqueous solution, the complex dissociates to give ions. `[Co(NH_(3))_(5)CI]CI_(2)OVERSET(("aq"))to[Co(NH_(3))_(5)CI]^(+)2CI^(-)` This means that one chlorine ATOM is present in the cooedination sphere. For more details, consult Unit-9 (Co-ordination compounds).

Discussion

48.	If the freezing point of 0.01 molal aqueous solution of a cobalt (III) chloride-ammonia complex (which behaves as strong electrolyte) is -0.0558^(@)C, the number of chloride (s) in the coordination sphere of the complex is(k_(f) of water =1/86K kg mol^(-1))
Answer» Solution :`((DeltaT_(f))_(obs))/((DeltaT_(f))_(CAL))=i=3` which shows `[Co(NH_(3))_(5)Cl]Cl_(2) to [Co(NH_(3))_(5)Cl]^(2+)+2Cl^(-)`

Discussion

49.	If the four tubes of a car are fitted to the same pressure with N_(2), O_(2), H_(2) and Ne separately then which one will be filled first?
Answer» `N_(2)` `O_(2)` `H_(2)` Ne Answer :C

Discussion

50.	If the fragment of one strand in DNA molecule has the base sequence CCATGCATG, what is the base sequence of complementary strand ?
Answer» Solution :Base sequence of COMPLEMENTARY STRAND of DNA is GGTACGTAC.

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

In a closed flask of 5 litres, 1.0 g of H_(2) is heated from 300 to 600 K. Which statement is/are correct?

If the initial concentration of reactants in a certain reaction is doubled the half life period of the reaction doubles . The order of the reaction is :

In a closed insulated container, a liquid is stirred with a paddle to increase the temperature. Which of the following is true ?

In the initial cocnentration is reduced to 1/4th of the initial value of a zero order reaction the half life of the reaction

In a closed containerr, a liquid is stirred with a paddle to increse the temperature. Which of the following is true?

If the hydrogen ion concentration of a given solution is 5.5 xx 10^(-3) " mol litre"^(-1), the pH of the solution will be

In a closed insulated container, a liquid is stirred with a paddle to increase its temperature. In this process, which of the following is true

In a closed container of capacity V with N_(2)(g) and wate vapour at 298 k, the pressure observed is 1.8 atm. If the volume is squeezed to V/3, then the preesue of the container is….., if aq. Tension of H_(2)O(g) is 0.2 atm at 298 K.

If the hydrogen ion concentration of a given solution is 5.5 xx 10^-3 M. Find the pH of the solution.

In a closed container NO_(2) gas is getting dimerised into N_(2)O_(4) gas with first order kinetics. Pressure after 10 hours of reaction is 5 atm and pressure after completion of reaction is 4atm. What is half life in hours?

If the highest oxidation states shown by any Lanthanide and any Actinide are +X and+Y, the sum of X+Y is euqal to?

if the heat of neutralisation for a strong acid- base reaction is -57.1 kJ, would be the heat released when 350 cm^(3)of 0.20 M ofa dibasic strong acid is mixed with 650 cm^(3) of 0.10 M monoacidic base ?

If the heat of formation of CO_(2) is -393 kJ. The amount of heat evolved in the formation of 0.156 kg of CO_(2) is

If the heat of combustion of carbon monoxide at constant volume and at 17^(@)C is - 283.3 kJ, then its heat of combustion at constant pressure (R=8.314 J degree^(-1) mol^(-1)

In a close packing of atoms A of radius r_(a), the radius of atom B that can be fitted in tetrahedral void is

If the half-life period of a first order reaction is 138.6 minutes, then the value of decay constant for the reaction will be

In a close-packed structure, if r is the radius of the spherical void and R is the radius of the spheres forming voids, the critical r/R value for the tetrahedral void is equal to

If the half-life of an isotope X is 10 years, its decay constant is

In a close packed structure of mixed oxides , the lattice is composed of oxide ions , one eighth of the tetrahedrai voids are occupied by divalent cations ( A ) while half of the octahedral voids are occupied by trivalent cations ( B ) . What is the formula of the oxide ?

If the half life period for a reaction in A is 100 min . How long will it take [A] to reach 25 % of its initial concentration ?

In a close packed structure of mixed oxide, the lattice is composed of O^(2-) ions. One eighth of tetrahedral voids are occupied by divalent cations A^(2+) and one half of octahedral voids by trivalent cations B^(3+) What is the formula of oxide ?

If the half-life of a radioisotope is 4 days, then how long would it take for 75% disitegration of the sample?

In a close packed centred cubic lattice of potassium the corrcet relation between the atomic radius (r)of potassium and the edge length (a) of the cube is

If the half cell reactions are given as (i) Fe_((aq))^(2+)+2etoFe_((s)),E^(o)=0.44V (ii) 2H_((aq))^(+)+(1)/(2)O_(2(g))+2etoH_(2)O_((l)),E^(o)=+1.23V The E^(o) for the reaction Fe_((s))+2H^(+)+(1)/(2)O_(2(g))toFe_((aq))^(2+)+H_(2)O_((l))

In a close packed lattice containing 'n' particles, the number of tetrahedral and octahedral voids respectively

In a close packed arrangement of N spheres, how many i) tetrahedral and (ii) octahedral sites are present ?

If the half life of a first order reaction is 60 min, the approximate time in min, required to complete 90% of the reaction is (log2=0.3)

In a classroom, the teacher has explained the quantitative aspects of electrolysis by stating the Faraday's laws of electrolysis. Calculate the quantity of electricity required to deposit 0.09 g of aluminium during the following electrode reaction: Al^3 + 3e^(-) to Al ( Al=27u)

If the half cell reaction A+e^(-)toA^(-) has a large negative reduction potential,it follows that

In a close pack array of n spheres, the number of tetrahedral holes are :

If the half cell reaction A to e^(-) to A^(-) has a larger negative potential , it follows that :

If the half-cell reaction A +e rarr A^(-) has a large negative reduction potential, it follows that

If the half cell reaction A +e rarr A^- has a large negative reduction potential, it follows that :

If the greenhouse effect or global warming remains unchecked, it alter :

In a classroom discussion about order and moleculrity of a reaction,Ramu argued that ''there are reactions which appear to be of higher order but actually follows first order kinetics''How far is his statement true? Give your opinion in this regard. Justify your answer using suitable example.

State the Faraday's laws of electrolysis

If the gold number of potato starch is 25, how many grams of it is required to prevent coagulating of 100mL of gold sol on adding 10mL of 10% NaCl solution?

In a classroom, the teacher has explained the quantitative aspects of electrolysis by stating the Faraday's laws of electrolysis.Explain the term electrochemical equivalent

If the given four electronic configurations (i) n = 4, l = 1 (ii) n = 4, I= 0 (iii) n = 3, l = 2 (iv) n = 3, I= 1 are arranged in order of increasing energy, then the order will be

If the geometry of [PtCl_(4)]^(2-) is square planar, which orbitals of Pt are involved in the bonding ?

In a chemical reaction K_(2)Cr_(2)O_(7)+xH_(2)SO_(4)+ySO_(2)toK_(2)SO_(4)+Cr_(2)(CO_(4))_(3)+zH_(2)O the values of x,y,z are

If the freezing point of a 0.01 molal aqueous solution of a cobalt(III) chloride-ammonia complex (which behaves as a strong electrolytes) is -0.0558^(@)C, the number of chloride(s) in the coordination sphere of the complex is [K_(f) of water =1.86 Kkgmol^(-1)]

In a chemical reaction triangleH=150kJ and triangleS= 100JK^-1 at 300K. The triangleG for the reaction is :

If the freezing point of 0.01 molal aqueous solution of cobalt (III) chloride-ammonia complex (which behaves as a strong electrolyte) is -0.0558^(@)C, the number of chloride(s) in the coordination sphere of the complex is (K_(f)" of water "="1.86 K kg mol"^(-1))

In a chemical reaction, the rate constant for the backward reaction is 7.5xx10^(-4) and the equilibrium constant is 1.5.The rate constant for the forward reaction is :

If the freezing point of a 0.01 molal aqueous solution of a cobalt (III) chloride-ammonia complex (which behaves as a strong electrolyte) is -0.0558^(@)C, the number of chloride (s) in the coordination sphere of the complex if [K_(f) of water =1.86 K kg mol^(-1)]

If the freezing point of 0.01 molal aqueous solution of a cobalt (III) chloride-ammonia complex (which behaves as strong electrolyte) is -0.0558^(@)C, the number of chloride (s) in the coordination sphere of the complex is(k_(f) of water =1/86K kg mol^(-1))

If the four tubes of a car are fitted to the same pressure with N_(2), O_(2), H_(2) and Ne separately then which one will be filled first?

If the fragment of one strand in DNA molecule has the base sequence CCATGCATG, what is the base sequence of complementary strand ?