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.

[Kr]4d^(10) 5s^(2) 5p^(4) is the electronic configuration of ___________.

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SOLUTION :TELLURIUM
2.

Kr and fluorine gases are irradiated with SbF_(5) it forms ……………. .

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SOLUTION :`KrF_(2).2SbF_(3)`
3.

K[ptCl_3(C_2H_4)] is Fischer salt.

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SOLUTION :Zeise SALT
4.

K_(p)andK_(c) are related by K_(p)=K_(c)(RT)^(Deltan). Under what practical condition/s, K_(p)=K_(c) ?

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RT = 1
T = 12K
`Deltan = 0`
`Rprop1/T`

Answer :C
5.

K_p of the reaction, N_2O_4(g)hArr2NO(g) at 773K is 640 mm of Hg. If the equilibrium pressure is 160 mm of Hg, then whatpercent of N_2O_4 will be dissociated? At what pressure will its degree of dissociation be 50%?

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Solution :Let initial NUMBER of MOLES of `N_O_2`=1 mol and the DEGREE of dissociation of `N_2O_4` at equilibrium`=prop`
`N_2O_4(g) Number of moles at equilibrium: `1-prop""2prop`
Total number of moles at equilibrium
`=1-prop-2prop=1+prop`
At equilibrium
`P_(N_2O_4)=((1-prop)/(1+prop))xx160` and `P_(NO_2)=((2prop)/(1+prop))xx160`
`K_p=(p_(NO_2)^2)/(p_(NO_2O_4))=(4prop^2xx160)/(1-prop^2)`or`640=(4prop^2xx160)/(1-prop^2)`
`:.prop=0.707`
`:.` PERCENT dissociation of `N_2O_4=70.7%`
Let, at a pressure of p mm Hg, the degree of dissociation of `N_2O_4` is 0.5
`:p_(N_2O_4)=((1-0.5)/(1+0.5))p=p/3mmHg`
and `p_(NO_2)=((2xx0.5)/(1+0.5))p=(2p)/3 mm Hg`
`K_p=(p_(NO_2)^2)/(p_(N_2O_4))=((2p)/(3)^2)/(p/3)=(4p)/3`or`(4p)/3=640`
`:.` p=480 atm
6.

(K_(P))/(K_(C)) for the gaseous reaction – (a) 2 A + 3 B hArr2C (b) 2 AhArr 4B (c) A + B + 2ChArr4D would be respectively -

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`(RT)^(-3) , (RT)^(2), (RT)^(@)`
`(RT)^(-3) , (RT)^(-2), (RT)^(-1)`
`(RT)^(-3) , (RT)^(2), (RT)`
NONE of the above

Answer :A
7.

K_p/K_c for the reaction: CO(g)+1/2O_2(g) hArr CO_2(g) is :

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1
RT
1/(sqrtRT)
RT^(1/2)

ANSWER :C
8.

The ratio of K_(p)// K_(c ) for the reaction :CO(g)+(1)/(2)O_(2)(g)hArr CO_(2)(g)is:

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1
RT
`1//sqrt(RT)`
`(RT)^((1//2)`

ANSWER :C
9.

K_(p) for the reaction PCl_(5)(g)ghArrPCl_(3)(g)+Cl_(2)(g) at 250^(@)C is 0.82. Calculate the degree of dissociation at given temperature under a total pressure of 5 atm. What will be the degree of dissociation if the equilibrium pressure is 10 atm, at same temperature.

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`27.5^(@)`
`23%`
`35.5%`
`40%`

ANSWER :A
10.

K_p for the reaction: N_2O_4(g) iff 2NO_2(g)is 0.66 atm at 320 K. Calculate the degreeof dissociation of N_2O_4 at 320 K and 380 mm. Also calculate the partial pressures of N_2O_4 and NO_2at equilibrium.

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SOLUTION :0.497, 0.332 ATM, 0.168 atm
11.

K_pfor the reactionN_2O_4(g) = 2NO_2(g)is 0.66 at 46^@C . Calculate the per cent dissociation of N_2O_4 at 46^@Cand a total pressure of 380 mm. What are the partial pressures of N_2O_4 and NO_2at equilibrium?

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SOLUTION :0.168 ATM, 0.332 atm
12.

K_(p) for the reaction H_(2)(g)+(1)/(2)O_(2)(g)hArrH_(2)O(l) is 8.0 "bar"^(-3//2) at T kelvin temperature. If vapour pressure of H_(2)O is 2.0 bar at same temperature then K_(P)^(0) for the reaction 2H_(2)(g)+O_(2)(g)hArr2H_(2)O(g) is

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`8.0`
64
16
256

Solution :`H_(2)(g)+(1)/(2)O_(2)(g)hArrH_(2)O(L)`
`k_(p_(i))=8"BAR"^(-3//2)`
`H_(2)O(l)hArrH_(2)O(g)`
`K_(p_(2))=V.P.` of `H_(2)O=2` bar
`H_(2)(g)+(1)/(2)O_(2)(g)hArrH_(2)O(g)`
`K_(P)=K_(p_(i))xxk_(p_(2))`
`2H_(2)(g)+O_(2)(g)hArr2H_(2)O(g)`
`K_(p)=(k_(p_(1))xxK_(p_(2))^(2)`
`(8xx2)^(2)"bar"^(-1)=256 "bar"^(1)`
`k_(p)^(0)=256`
13.

K_(p)for the reaction :CO_(2)(g)+H_(2)(g) hArr CO(g)+H_(2)O(g)is found to be 16 at a given temperature. Originally equal number of moles of H_(2) andCO_(2)(g) were placed in the flask. At equilibrium, the pressure of H_(2) is 1.20 atm. What is the partial presure of CO_(2) and H_(2)O ?

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1.20 ATM. each
2.40 atm. each
4.80 atm each
9.60 atm each

Answer :C
14.

K_(p) for the reactionMgCO_(3_((s))) to MgO_((s)) + CO _(2_((g)))" is" 9 xx 10^(-10). CalculateDelta G^(@) for thereactionat 25^(@)C.

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Solution :Given : `K_(p) = 9 xx 10^(-10)`
Temperature`= T = 273+ 25 =298 K `
`Delta G^(@) = ? `
`Delta G^(@) =- 2 .303RT log_(10) K_(p)`
`=-2.303x 8.314 xx 298 xx log_(10) 9 xx 10^(-10)`
`=- 2.303 xx 8. 314 xx 298 xx [bar(10).9542]`
`=- 2.303 xx 8.314 xx 298 xx [ - 9.0458]`
`= 51683 J mol^(-1)`
`=51. 683 kJ mol^(-1)`
15.

K_(p)for thereaction2SO_(2(g))+ O_(2(g))to2SO_(3(g))" is" 7.1 xx 10^(24)at25^(@)C . CalculateDelta G^(@)for thereactions. (R= 8. 314KJ^(-1) mol^(-1))

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Solution :`DELTA G^(@)=- 141.8 KJ mol^(-1)`
16.

k_(P) for the following reaction at 700 K is 1.3xx10^(-3)atm^(-1) The K_(c) at same temperature for the reaction 2SO_(2)+O_(2)hArr2SO_(3) will be

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`1.1xx10^(-2)`
`3.1xx10^(-2)`
`5.2xx10^(-2)`
`7.4xx10^(-2)`

SOLUTION :`K_(p)=K_(C)(RT)^(Deltan)hArrR="Gas CONSTANT"`
`K_(c)=(K_(p))/((RT)^(Deltan))=(1.3xx10^(-3))/((0.0821xx700)^(-4))=7.4xx10^(-2)`
17.

K_(p) and K'_(p) are the equilibrium constants of the two reactions, given below 1/2N_(2(g))+3/2H_(2(g))hArrNH_(2(g))N_(2(g))+3H_(2(g))hArr2NH_(3(g)) Therefore, K_(p) and K'_(p) are related by

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`K_(p)=K_(p)^(2)`
`K_(2)sqrt(K'_(p))`
`K_(p)=2K'_(p)`
`K_(p)=K'_(p)`

Solution :When a balanced equation having equlibrium constant `K_(p)` is MULTIPLIED by a certain VALUE n, the equlibrium constant for the new equation will be equal to `(K_(p))^(n).` In the GIVEN equation, `n=2`
So, `K'_(p)=(K_(p))^(2)orK_(p)=sqrt(K'_(p))`
18.

K_(p)and K'_(p) are equilibrium constants of the two reactions given below :(1)/(2)N_(2)(g)+(3)/(2)H_(2)(g) hArr NH_(3)(g)N_(2)(g)+3H_(2)(g)hArr 2NH_(3)(g)Therefore K_(p) and K'_(p) are related by :

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`K_(p)=K'_(p)^(2)`
`K_(p)=sqrt(K'_(p))`
`K_(p)=2K'_(p)`
`K_(p)=K'_(p)`

Answer :B
19.

Kolbe's synthesis of sodium salt of butanoic acid gives:

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n-hexane
Isobutane
Butane
Ethene

Answer :A
20.

Kolbes - Schmidt reaction is used to prepare

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SALICYLIC acid
salicylaldehyde
phenyl acetate
o-xylene

Answer :A
21.

Kolbe's electrolysis of potassium succinate gives CO_(2) and_____.

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SOLUTION :ETHYLENE or ETHENE.
22.

Kolbe-schmidt reaction is used for

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SALICYLIC acid
Salicylaldehyde
Phenol
Hydrocarbon

Answer :A
23.

Kolbe'ssynthesisof sodiumsaltof butaneacidgives :

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N- HEXANE
iso-BUTANE
n- butane
PROPANE

ANSWER :A
24.

Kolbe-Schmidt reaction is used for:

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SALICYLIC acid
Salicylaldehyde
Phenol
Hydrocarbon

Answer :A
25.

Kolbe 'seletrolyticmethodcan beapplied on :

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`CH_(3)COONa`
`{:(CH_(2)COOK),(|),(CH_(2)COOK)`
`{:(HC-COOK),(" "||),(HC-COOK):}`
`C_(6)H_(5)COONa`

ANSWER :A,B,C
26.

Kohlraush's law is applied to calculate

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MOLAR conductance at INFINITE DILUTION of a weak electrolyte
degree of dissociation of weak electrolyte
solubility of a SPARINGLY soluble salt
all of the above

Answer :D
27.

Kohlrausch's law is used to calculate

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`^^_(m)^(OO)`
`LAMBDA^(0)` c area
both
`lambda^(0) m C_(6)H_(12)O_(6)`

Solution :Statement of LAW.
28.

Kohlrausch's law is applied to calculate …………….. .

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molar conductance at infinite dilution of a weak ELECTROLYTE
degree of DISSOCIATION of weak electrolyte
solubility of a SPARINGLY SOLUBLE salt
all the above

Answer :D
29.

Kohlrausch's law helps to determine the degree of dissociation of a weak electrolyte at a given concentration.The molar conductivityLambda_mof .001M acetic acid is 4.95xx10^(_5)Scm^2mol^(-1).Calculate the degree of dissociation(alpha)at this concentration if limiting molar conductivitylamda_m^0for H+is 340xx10^(-5)Scm^2mol^(-1)and CH_3COO^-50.5xx10^(-5)Scm^2mol^(-1)

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SOLUTION :`lamda_m^0CHCOOH=4.95XX10^(-5)Scm^2mol^(-1)`
`lamda_m^0CH_3COOH=lamda_m^0CH_3COO^(-)+H^+`` alpha=lamda_m^0/lamda_x10^(-5)m^0=(4.95xx10^(-5))/(390.5xx^(-5))=0.0126`
30.

Kohlrausch law states that at

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infinite dilution, each ion MAKES definite contribution to conductance of an electrolyte whatever be the nature of the other ion of the electrolyte
infinite dilution, each ion makes definite contribution to equivalent conductance of an electrolyte, whatever be the nature of the other ion of the electrolyte
finite dilution, each ion makes definite contribution to equivalent conductance of an electrolyte, whatever be the nature of the other ion of the electrolyte
infinite dilution each ion makes definite contribution to equivalent conductance of an electrolyte depending on the nature of the other ion of the electrolyte.

Solution :At infinite dilution, when dissociation is complele eachion makes a definite contribution to WARDS molar conductance of the electrolye irrespective of the nature of the other ion with which its is associated and that the molar conductance of any electroylte at infinite dilution is given by the SUM of the contributions of two IONS. This is CALLED Kohlrausch law.
`Lambda_(m)^(oo) = Lambda_(+)^(oo) + Lambda_(-)^(oo)`
`Lambda_(1)^(oo) and Lambda_(-)^(oo)` are molar ionic conductance at infinite dilution,for cations and anions, respectively.
31.

Kohlrausch's law helps to determine the degree of dissociation of a weak electrolyte at a given concentration.State Kohlrausch's law.

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Solution :It states that the limiting molar CONDUCTIVITY of an electroylte is the sum of limiting molar ionic CONDUCTIVITIES of ANIONS and CATIONS.
32.

Kohlrausch law can be used to find the molar conductivity of a weak electrolyte at infinite dilution.

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ANSWER :1
33.

Kodel polyester is formed by trans-esterification of dimethyl terephthalate with 1,4-di (hydroxymehyl) cyclohexane. Write its reaction ?

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SOLUTION :
34.

Kohlrausch’s law states that at

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finite DILUTION, each ion MAKES definite contribution to the equivalent CONDUCTANCE of an electrolyte, whatever be the NATURE of the other ion of the electrolyte.
infinite dilution, each ion makes definite contribution to equivalent conductance of an electrolyte DEPENDING on the nature of the other ion of the electrolyte.
infinite dilution, each ion makes definite contribution to conductance of an electrolyte whatever be the nature of the other ion of the electrolyte.
infinite dilution, each ion makes definite contribution to equivalent conductance of an electrolyte, whatever be the nature of the other ion of the electrolyte.

Answer :D
35.

KOH can be used as drying agent for

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AMINES
Phenols
Acids
Esters

Solution :Amines is CORRECT because they do not reactwith KOH because both amines and KOH are BASES. Restcan REACT.
36.

KO_2 (potassium superoxide) is used in oxygen cylinders in space and submarines because it

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Absorbs `CO_(2)` and increases `O_(2)` CONTENT
Eliminates moisture
Absorbs `CO_(2)`
Produce ozone

Solution :`KO_(2)` is used in oxygen cylinder because it absorbs `CO_(2)` and increases `O_(2)` content. SUPER OXIDES reacts with water to give `H_(2)O_(2)& O_(2)`
37.

KO_(2) (potassium superoxide) is used in oxygen cylinders in space and submarines because it :

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1. ABSORBS `CO_(2)` and increases `O_(2)` content
2. ELIMINATES moisture
3. absorbs `CO_(2)`
4. produces ozone

Solution :`4KO_(2)+2CO_(2)to2K_(2)CO_(3)+3O_(2)`
38.

KO_2 + CO_2 to ?(gas)

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`H_(2)`
`N_(2)`
`O_(2)`
`CO`

Solution :`2KO_(2) + CO_(2) to K_(2)CO_(3) +3/2O_(2)`
39.

KO_2 is used in oxygen cylinders in space and submarines because it

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ABSORBS `CO_2` and INCREASES `O_2` CONTANT
ELIMINATES moisture
absorbs `CO_2`
PRODUCE Ozone

Answer :A
40.

Known trihalide of N is:

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`NF_3`
`NCl_3`
`NBr_3`
`NI_3`

ANSWER :A
41.

Knowing the electron gain enthalpy values of O rarr O^(-) and O rarr O^(2-) as -141 and 702 kJ mol^(-1) respectively, how can you account for the formation of a large number of oxides having O^(2-) species and not O^(-) ?

Answer»

Solution :Consider the reaction of a divalent metal (M) with oxygen. The formation of `MO_(2)` and MO involves the following steps :
`{:(M(g) overset(Delta_(i)H_(1))RARR M^(+)(g) overset(Delta_(i)H_(2))rarr M^(2+)(g) ","O(g) overset(Delta_(eg)H_(1))rarr O^(-)(g)overset(Delta_(eg)H_(2))rarr O^(2-)(g)),(M^(2+)(g)+2O^(-)(g) overset("Lattice energy")rarr M^(2+)(O^(-))_(2)(s)","M^(2+)(g) overset("Lattice energy")rarr M^(2+) O^(2-)(s)):}`
If electron gain enthalpy were the only factor involved in the formation of `O^(2-)` ions, we would expect that O will prefer to form `O^(-)` rather than `O^(2-)` ions. ACTUALLY a large number of oxides have `O^(2-)` species and not `O^(-)`. This is due to the following two reasons : (i) `O^(2-)` has the stable noble GAS configuration (ii) Due to higher charge on `O^(2-)` than on `O^(-)` ions, the lattice energy released during the formation of oxides containing `O^(2-)` species in the solid state is MUCH higher than lattice energy released during the formation of oxides having `O^(-)` species. In other words, it is the higher lattice energy of formation of oxides containing `O^(2-)` species which more than compensates the higher electron gain enthalpy `(Delta_(eg)H_(2))` needed during formation of `O^(2-)` from `O^(-)` ions. Thus, formation of oxides containing `O^(2-)` species is energyetically more favourable than oxides containing `O^(-)` species. It is because of this reason that oxygen forms a larger number of oxides having `O^(2-)` species and not `O^(-)`.
42.

Knowing the electron gain enthalpy values for O to O^(-) and O to O^(2-)as -141 and 702 kj mol-1 respectively, how can you account for the formation of a large number of oxides having O^(2-)species and not O^(-)?

Answer»

Solution :The VALUES of ELECTRON gain ENTHALPY suggest that formation of `O^(2-)`is endothermic. However, `O^(2-)`has most stable CONFIGURATION in `s_2 np_6`. In SOLID state, the lattice energies of the oxides having `O^(2-)`anions are very high which compensates the positive electron gain enthalpy of oxide (`O^(2-)`) formation. Thus, more oxides with `O^(2-)`ion are formed.
43.

Knowing the electron gain enthalpy values forO to O^(-)and O to O^(2-) as- 141 and 702 kJ "mol"^(-1)respectively, how can you account for the formation of a large number of oxides having O^(2-)species and not O^(-) ?

Answer»

SOLUTION :The second electron enthalpy of oxygen for the formation of `O^(2-)`is positive while first electron gain enthalpy of oxygen for the formation of `O^-`is negative. This means that if electron gain enthalpy is the only factor involved for the formation of divalent ions, we would expect that oxygen would prefer to form `O^-`ions rather than `O^(2-)`ions. ACTUALLY, a large number of oxides have `O^(2-)`species and not `O^-`. This is because (i) Divalent `O^(2-`) has the stable noble gas CONFIGURATION (II) In the solid state, large amount of energy KNOWN as lattice enthalpy is released to form divalent `O^(2-)`ions than monovalent `O^-` ions. It is the greater lattice enthalpy of `O^(2-)`ions which compensates for the high energy required to remove the second electron. This is responsible for greater stability of `O^(2-)`ions as compared to `O^-`ions.
44.

Knowing the electron gain enthalpy values for O to O^(-) and O to O^(2-) as -141 and 702 kJ " mol"^(-1) respectively , how can you account for the formation of a large number of oxides having O^(2-) speciesand not O^(-) ?

Answer»

Solution :Consider the reaction of a divalent metal ( M) with oxygen . The formation of `M_2O and MO` involves the following steps :
`M(g) overset(Delta_i, H_1)to M^(+) (g) overset(Delta_i/ H_2) to M^(2+) (g)`
`Deltai H_1 and Delta_i H_2` are first and second ionisation enthalpies of the metal M .
`O(g) overset(Delta_(eg) H_1) to O^(-) ( g) overset(Delta_(eg)H_2)to O^(2-)(g)`
`Delta_(eg) H_1 and Delta_(eg)H_2` are first and second ELECTRON gain enthalpies
`2M^(+)(g) + O^(-)(g) overset("Lattice energy")to M_2O (s)`
`M^(2+)(g) + O_(2)^(-)(g) overset("Lattice energy ")to MO(s)`
Although `Delta_i H_2` is much more than `Delta_i H_1 and Delta_(eg) H_2` is much higher than `Delta_(eg)H_1`, yet the lattice nenergy of formation of MO(s) due to higher charges is muchmore than that of `M_2O(s)`. In other words, formation MO is energetically more favourable than `M_2O`. It is due to this reason that oxygen forms PREFERABLY oxides having the `O^(2-)` species and not `O^(-)`.
45.

Knowing that the chemistry of lanthanoids (Ln) is dominated by its +3 oxidation state, which of the following statement is incorrect?

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The ionic sizes of LN(III) decreases in general with increasing atomic number
Ln(III) COMPOUNDS are generally colorless
Ln(III) hydroxides are mainly basic in character
Because of the large size of the Ln(III) ions, the BONDING in its compounds is perdominantly ionic in character

Solution :THEORY based
46.

Knowing that the chemicstry of lanthanoids(Ln) is dominated by its +3 oxidation state, which of the following statements is incorrect ?

Answer»

The ionic sizes of Ln(III) DECREASE in GENERAL with increasing atomic number.
Ln(III) compounds are generally colourless
Ln(III)hydroxides are mainly basic in character
Because of the large size of the Ln(III) ions, the bonding in its compounds is predominantly ionic in character.

Solution :Ln(III)compounds are generally coloured due to PARTLY filled f-orbitals which PERMIT f-f transition.
47.

Knowing that the Chemistry of lanthanoids (Ln) is dominated by its+3 oxidation state, which of the following statement is incorrect?

Answer»

Because of the LARGE size of the Ln (III) ions the bonding in its compounds is predominantly ionic in character
The ionic sizes of LU (III) DECREASE in general with increasing atomic number
Lu (III) compounds are generally colourless
Lu (III) hydroxide are mainly basic in character

Solution :The most common oxidation state of lanthanoid is +3. Lanthanoids in +3 oxidation state USUALLY have unpaired electron in f-subshell and impart characterristic colour in SOLID as well as in solution state due to f-f transition. (Except lanthanum and lutetium).
48.

Knocking sound occurs in engine when fuel

Answer»

Ignites slowly
Ignites rapidly
CONTAINS water
Is mixed with machine oil

Solution :Knocking -Sudden and IRREGULAR burning of the fuel mixture causing JERKS against the piston and give rise to violent sound. This is KNOWN as knocking.
49.

Knowing that average kinetic energy of an ideal gas (X) is directly proportinal to absolute temperature, if T_(1)=273K, which statements describe the other curves?

Answer»

CURVE A is for heavier GAS but at same temperature
Curve B is for the same gas but at `373K
Curve A is for the same gas but at `373K
Curve B is for lighter gas but a same temperature

Answer :A::B::D
50.

KNO_(2)+AgF to AgNO_(2)darr+KF

Answer»

For PRECIPITATE FORMATION formation reaction
For precipitate DISSOLUTION reaction
For precipitate EXCHANGE reaction
For no reaction

Answer :a