Explore topic-wise InterviewSolutions in .

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

92101.

5 milli-moles of a solid A was dissolved in 5 moles of H_(2)O. On adding to the solvent, A starts polymerising into another insolublesolid following zero order kinetics. On adding 6 milli-moles of another solid solute C (after 20 minute) the polymerisation completely stops. The insoluble solid polymer is removed and the resulting solution was cooled to a temperature less then .-0.186^(@)C (freezing point of solution ) to cause solidification of some liquid water . Calculate the value of Xif rate constant for polymerisation reaction is represented as 10^(-X) moles//minute. [K_(f) (H_(2)O)= 1.86 K - Kg "mole"^(-1)]

Answer»


ANSWER :4
92102.

5 milli-moles of a solid A was dissolved in 5 moles of H_(2)O. On adding to the solvent , A sstarts spolymerising into another insoluble solid following zero order kinetics. On adding 6 milli-moles of another solid solute C (after 20 minute) the polymerisation compeletly stops. The insoluble solid polymer is removed and the resulting solution was cooled tova temperature less then -0.186^(@) C(melting point of solution) to cause solidification of some liquid water. Calculate the value of 'X' if rate constant for polymerisation reaction is represented as 10^(-X)mole//minute. [K_(f)(H_(2)O)=1.86 K-kg "mole"^(-1)]

Answer»


ANSWER :4
92103.

5 litres of a solution contains 25mg of CaCO_(3). What is its concentration in ppm ?

Answer»


ANSWER :5
92104.

5 litre solution of 0.4M CuSO_((aq)) is electrolysed using Cu electrode. A currentof 482.5 ampere of passed for 4 minute. The concentrations of CuSO_4 left in solution is

Answer»

0.16 M
0.32 M
0.34 M
0.40 M

Solution :LET us suppose `K_1` and `K_2` are the SPECIFIC conductance of solutions 'A' and 'B' REPECTIVELY and CELL constant is 'y'. We know that, Specific conductance = Conductance `xx` Cell constant
(A), `k_1` = `1/50xxy`For (B), `k_2` = `1/100xxy`
When EQUAL volume of (A) and (B) are mixed, the volume becomes double. then,
Specific conductance of mixture = `(k_1+k_2)/2`
`:. (k_1 + k_2)/2=1/Rxxy``1/2[y/50+y/100]=1/Rxxy`
`1/100+1/200=1/R`
R=`200//3`=66.66 ohm
92105.

5-Hydroxyhexanal forms a six member hemiacetal, which predominates at equilibrium in aqueous solution. How many stereoisomers are possible for this cyclic hemiacetal?

Answer»

Solution :(4)

(Two CHIRAL CARBONS HENCE four stereoisomers)
92106.

5 gm of CaCO_(3) is made to react with 0.2M, 100ml HCl solution. What will be the volumes of CO_(2)gas evolved at NTP?

Answer»

2240ml
224ml
22.4L
224L

Solution :LR
`CaCO_(3)+ 2HClrarrCaCl_(2)+H_(2)O+CO_(2)`
mole `(5)/(10)=0.05 (0.2xx100)/(1000)=0.02`
`n_(CO_(2))` produce `=(n_(HCl))/(2)=(0.02)/(2)=0.01`
`V_(CO_(2))NTP=22.4xx0.01` LITRE
`=22400xx0.01ml`
=224'ml
92107.

5 g of Na_(2) SO_(4) was dissolved in x g of H_(2)O. The change in froczing point was found to be 3.82^(@)C. If Na_(2)SO_(4) is 81.5% ioniscd, the value of x (K_(f)for water =1.86 ^(@)C kg mol ^(-1)) is approximately: (molar mass of S = 32 g mol ^(-1)) and that of Na=23 g mol ^(-1))

Answer»

15 G
25 g
45 g
65 g

Solution :Molarity (cxpcrimental)
` = (DELTA T _(f))/(K _(f)) = (3.82)/( 1.86) =(3.82)/(1.86)= 2.054` mol/1000 g solvent
Molarity (thcartical) `= ("mole of solute")/("wt. of solventing(g))xx1000`
`= ( 5g//142 g //"mole")/(x) xx1000`
`Na_(2) SO_(4) to 2NA^(+) +SO_(4)^(2-)`
`{:("Moles before dissociation", 1,0,0),("Moles after dissociation", 1-x, 2x, x):}`
Von't FACTOR (i) `= ("Moles after dissociation")/("Moles before dissociation")`
`= ((1-x 0 + 2x+x)/( 1)`
`Na_(2) SO_(4)` is ionised `81.5%` means `x=0.815`
`=((1-0.815) + 2xx0.815 +0.815)/(1) =2.63.`
`i = ("Observed molarity ")/("Calculated molarity")`
`implies 2.63 =(2.054)/((0.0352)/(x)XX 1000) =45.07g.`
92108.

5 g sample contain only Na_(2)CO_(3)and Na_(2)SO_(4)This sample is dissolved and the volume made up to 500 mL. 25 mL of this solution neutralizes 20 mL of 0.1 M H_(2)SO_(4). Calculate the percentage of Na_(2)SO_(4) in the sample.

Answer»


Solution :Only `Na_(2)CO_(3)` reacts with `H_(2)SO_(4)`
`Na_(2)CO_(3) + H_(2)SO_(4) to Na_(2)SO_(4) + H_(2)CO_(3)`
= `20 XX 0.1 =2`
no. Of moles of `Na_(2)CO_(3)` in 500 ML solution
`=500/25 xx 2= 40`
wt. Fo `Na_(2)CO_(3) = 40 xx 106 xx 10^(-3) = 4.24`G
= 84.8
92109.

5 g of hydrogen reacts with 32 g of oxygen to form moles of water

Answer»

1
2
3
4

Answer :B
92110.

5 g each of the following gases at 87^@C and 750 mm pressure are taken. Which of them will have the least volume :

Answer»

HF
HCl
HBr
HI

Answer :D
92111.

5 A current is passed through electrolytic cell filled with AgNO_(3) solution for 2.7 hours. If 1 spoon require 0.01 g silver to get coated, so calculate how many spoon get coated by silver obtained on the cathode ?

Answer»


ANSWER :5439 SPOON
92112.

4xx10^(-2) moles of a non-volatile solute is added into 10 moles of solvent.The solute plymerises into soluble solid following first order kinetics with rate constant equal to 0.693 min^(-1). If after 2 min, elevation in boiling point is observed to be 0.01^(@) then calculate which form the solute is getting polymerised into? Given : Molar mass of solvent=100 g//mole. K_(b) of solvent =0.5 K-kg mol^(-1) [Instruction : Mark 2 if polymer is dimer, 3 if trimer and so on.]

Answer»


ANSWER :3
92113.

4xx10^(-3) m^(3)H_(2)O_((i)) is placed in a closed cubic vessel of edge-length of 1 m at 400 K temperature. If the vapour pressure of water is 0.0842 atmosphoere with density 0.89 g cm^(-3) at the same temperature,how much is left behind in liquid state?

Answer»


ANSWER :`3.948` LIT
92114.

4Zn +10HNO_(3) to 4Zn(NO_(3))_(2) +NH_(4)NO_(3)+3H_(2)O. In this reaction one mole of HNO_(3)is reduced by

Answer»

32g Zn
64G Zn
128g Zn
26g Zn

ANSWER :4
92115.

4NH_3(g)+5O_2(g)to4NO(g)+6H_2O(g), is in equilibriumin a closed container of volume 1L at a given temperature. If the reaction is started with 1 mol NH_3(g) and 1 mol of O_2(g) and the number of mol of H_2O(g) at equilibrium is 0.6 mol, then at equilibrium-

Answer»

`[NH_3]=[NO]`
`[NO]LT[O_2]`
`[NO]GT[NH_3]`
`[O_2]lt[H_2O]`

ANSWER :B::D
92116.

4NH_3 + 5O_2 to 4NO + 6H_2O. If rate of formation of NO is 6 xx 10^(−4) "atm min"^(-1), calculate the rate of formation of H_2O.

Answer»

SOLUTION :`9.0xx10^(-4) "ATM MIN"^(-1)`
92117.

4Na+O_2 to 2Na_2O Na_2O+H_2O to 2NaOH In the given reaction, the oxide of sodium is……

Answer»

Acidic
BASIC
Amphoteric
Neutral

Solution :`Na_2O` from NAOH so that it is basic OXIDE.
92118.

4n + 2 series is known as:

Answer»

ACTINIUM series
thorium series
uranium series
neptunium series

Answer :C
92119.

4 L of 0.02 M aqueous solution of NaCl was diluted by adding 1 L of water. The molality of the resultant solution is……..

Answer»

0.004
0.008
0./012
0.016

Solution :`M_(1)V_(1)=M_(2)V_(2)`
`(0.02 M)xx(4L)=M_(2)xx(5L)`
`M_(2)=((0.0M)xx(4L))/((5L))`
=0.16 M
92120.

4L of water is added to 2L of 6M HCl. The molarity of the final solution is

Answer»

4M
2M
1M
0.5M

Solution :Final VOLUME ` = 2L + 4L = 6L`
molarity ` = (6 xx 2)/(6) = 2M`
92121.

4HNO_(3)+P_(4)O_(10)toHPO_(3)+ X In the above reaction the product X is:

Answer»

`NO_(2)`
`N_(2)O_(3)`
`N_(2)O_(4)`
`N_(2)O_(5)`

Answer :D
92122.

4L of 0.02 M aqueous solution of NaCl was diluted by adding one litre of water. The molality of the resultant solution is ……………… …

Answer»

0.004
0.008
0.012
0.016

Solution :`M_(1)V_(1)=M_(2)V_(2),0.02xx4=M_(2)XX5 or M_(2)=0.016`
92123.

4HBr+O_(2)to2H_(2)O+2Br_(2). The molecularity of the reaction appears as 5, but experimentally, it is 2. Explain.

Answer»

Solution :The mechanism of OXIDATION reaction of HBr is given in three STEPS.
`HBr+O_(2) to HOOBr, HOOBr+HBr to 2HOBr HOBr+HBr to H_(2)O+Br_(2)`
MOLECULARITY of each step is `2`.
The overall molecularity of the slowest step `(1st)` is `2`
92124.

4g of Substance A, dissolved in 100g H_(2)O depressed the freezing point of water by 0.1^(@)C . While 4g of another substance B, depressed the f.pt by 0.2^(@)C . What is the between molecular weights of A and B.

Answer»

`M_(A)=4M_(B)`
`M_(A)=M_(B)`
`M_(A)=0.5M_(A)`
`M_(A)=2M_(B)`

ANSWER :D
92125.

4g of copper was dissolved in conc. Nitric acid. The copper nitrate so obtained on strong heating gave 5 g of its oxide. The equivalent weight of copper is

Answer»

`23`
`32`
`12`
`20`

Solution :4g of copper gives 5 g of its OXIDE
`:.` 4 g of copper COMBINES with 1 g of oxygen
`:.` Mass of copper that combines with 8g of oxygen `8xx4=32`
`:.` Eq. mass of copper = 32
92126.

4f^(2) 5d^(0) 6s^(0) is the electronic configuration of lanthanoide ion

Answer»

only `Eu^(2+)`
only `Gd ^(3+) and Eu ^(2+)`
only `Eu^(2+) , Gd ^(3+) and Tb ^(4+)`
only `Eu^(2+) and Tb ^(2+)`

Answer :C
92127.

4f^(14) configuratoin is observed in

Answer»

YB and Lu
Dy and Pm
Lu and La
Tm and Lu

Answer :A
92128.

4f^(14) 5d^(0) 6s^(0) represents which of the followig ?

Answer»

`YB ^(3+)`
`LU^(3+)`
`Nb^(3+)`
`Lr ^(3+)`

ANSWER :B
92129.

4f^(0) , 5d^(0) 6s^(0) represents which one of the following

Answer»

`Ce ^(3+)`
`AC ^(3+)`
`LA ^(3+)`
`Ce ^(+2)`

ANSWER :C
92130.

4f and 5f-series has total number of elements

Answer»

13
12
14
28

Answer :D
92131.

4Cu+ 10HNO_(3) to Cu(NO_(3))_(2) + X + H_(2)O Mention the substance 'X'

Answer»

`NO_(2)`
`N_(2)O`
NO
`N_(2)O_(3)`

SOLUTION :`4Cu_(g) + underset("dilute")(10HNO_(3))(g) to 4Cu(NO_(3))_(2)(aq) + 5H_(2)O (L) + N_(2X) O_(g)`
92132.

4CH_(3)CH_(2)underset(O)underset(||)CH_(3) underset(H_(2)O)overset(NaBH_(4))to X what is X?

Answer»

`4CH_(3)CH_(2)UNDERSET(OH)underset(|)CH_(2)CH`
`4CH_(3)CH_(2)CH_(2)CH_(2)OH`
`4CH_(3)-underset(OH)underset(|)CH-CH_(3)`
`4CH_(3)CH_(2)CH_(2)OH`

Solution :`4CH_(3)CH_(2)-underset(O)underset(||)C- CH_(3) underset(H_(2)O)overset(NaBH_(4))to underset(" (Butan-2-ol)")(4CH_(3)-CH_(2)-underset(OH)underset(|)CH-CH_(3))`
92133.

4CH_(3)CH_(2)CH_(2)CHO underset(H_(2)O)overset(NaBH_(4))to X what is X?

Answer»

`4CH_(3)CH_(2)underset(OH)underset(|)CH_(2)CH`
`4CH_(3)CH_(2)CH_(2)CH_(2)OH`
`4CH_(3)CH_(2)CH_(2)underset(O)underset(||)CH_(3)`
`4CH_(3)- CH_(2)-CH_(2)-CH_(3)`

SOLUTION :`4CH_(3)CH_(2)CH_(2)CH_(2)OH`
92134.

Be^7_4 Captures K electrons into its nucleus. The mass no and atomic no. of new nucleus formed are

Answer»

7, 5
7, 4
6, 3
7, 3

Answer :D
92135.

4Ag_((s)) + 8CN_((aq))^(-) + 2H_2O_((l)) = O_(2(g)) to X + OH_((aq))^(-) then X = ………

Answer»

`[AG(CN)_(2)]^(-)`
`[Ag(CN)_(4)]^(-)`
`AgCN`
`[4Ag(CN)_2]^(-)`

ANSWER :D
92136.

4.90 g of KClO_(3) when heated produced 1.92 g of oxygen and the residue (KCl) left behind weighs 2.96 g. Show that these results illustrate the law of conservation of mass.

Answer»

Solution :Mass of `KClO_(3)` taken = 4.90 g
TOTAL mass of the product `(KCl+O_(2))=2.96+1.92=4.88g`
Difference betweenthe mass of the reactant and the total mass of the PRODUCTS = `4.90-4.88=0.02g`
This small difference may be DUE to EXPERIMENTAL error.
THUS, law of conservation of mass holds good within experimental errors.
92137.

4.9 g of H_(2) SO_(4) is present in500 cm^(3) of the solution has molarity.

Answer»

0.2
0.1
0.01
0.02

Solution :`M= "Mass"/("Molar mass" xx V (DM^(3)))`=`4.9/(98 xx 5)=1/10=0.1`
92138.

48 g of SO_(3) , 12.8 g of SO_(2) and 9.6 g of O_(2) are present in one litre . The respective active masses will be

Answer»

1.0 , 05 and 0.3
0.6 , 0.2 and 0.3
0.6 , 0.4 and 0.2
1.0 , 0.5 and 1.5

Answer :2
92139.

""_(4)^(7)Be captures a K-electron into its nucleus. What will be the mass number and atomic number of the nuclide formed?

Answer»

SOLUTION :When a nucleus captures a K-electron, a proton is converted to a NEUTRON. So the mass number does not change but the ATOMIC number REDUCES by 1 unit. Thus the mass number and atomic number of the resulting nuclide will be 7 and 3 respectively.
92140.

4.6 gm of liquid ethanol (C_(2)H_(5)OH) is taken in 12 litre container and at 27^(@)C, 40% of ethanol is vaporised till equilibrium. Now if volume of container is halved and system is allowed to attain equilibrium then find [Give: R=0.08atm/litre mole-k]

Answer»

Solution :`C_(2)H_(5)OH(L)hArrC_(2)H_(5)OH(g)`
Molet=0 0.1 0
`t=t_("eqm") 0.1-0.04 0.04`
=0.06
For gas PV=nRT `rArrP_(C_(2)H_(5)OH("gas"))=(nRT)/(V)=(0.04xx0.08xx300)/(12)`
`V.P_("gas")=0.08` atm (at `eq^(m)`)
=0.08xx100=8
92141.

4.6g of a polydric alcoholwas treated with an excess of methyl magnesium bromide to produce 3.36 liter of CH_(4) at STP. Calculate number of -OH(molecular weightof alcohol = 92)

Answer»


SOLUTION :N//A
92142.

4.58 g of NaCl was dissolved in 129 g of H_(2)O at 280 K. The osmotic pressure of the solution was found to be 2.606 magapascal. Density = 1.02 g/cc. Calculate osmotic coefficient.

Answer»


ANSWER :I=1.906
92143.

450 waves of a energy radiation passes in one minute from a point then what will be thewavelength of radiation :-

Answer»

`6.66xx10^(-5)` m
`4XX10^(7)` m
`2.25xx10^9` m
`2.5xx10^(-8)` m

SOLUTION :`lambda=C/v`
`=(3xx10^8)/(450/60)=(3xx10^8xx6)/45`
`=4xx10^7` m
92144.

45.4 L of dinitrogen reacted with 22.7 L of oxygen and 45.4 L of nitrous oxide was formed. The reaction is : 2N_(2)(g)+O_(2)(g) rarr 2N_(2)O(g) Which law is being obeyed in this experiment ? Write the statement of the law?

Answer»

Solution :As gases are reacting together to form GASEOUS products and the ratio of the volumes of `N_(2):O_(2):N_(2)O=45.4:22.7:45.4=2:1:2` which is a simple whole NUMBER ratio. Hence, the EXPERIMENT proves Gas LUSSAC's LAW of gaseous volumes.
92145.

4.5 moles each of hydrogen and iodine heated in a seated in a sealed ten litre vessel. At equlibrium, 3 moles of HI were found. The equilibrium constnt for H_(2(g))hArrPCl_(3(g))+Cl_(2(g)) is

Answer»

1
10
5
`0.33`

Solution :`H_(2)+I_(2)hArr2HI`
`{:("INITIAL conc.",4.5,4.5,0),("at Equlibrium",4.5-x,4.5-x,2x):}`
From euestion `2x=3`
`x=3/2=1.5`
So conc. At eqm. `4.5-1.5of H_(2)`
`=4.5-1.5of I_(2)and 3 of HI`
`K=([H]^(2))/([I_(2)][H_(2)])=(3xx3)/(3xx3)=1.`
92146.

45 grams of ethylene glycol (C_(2)H_(6)O_(2)) is mixed with 600 grams of water. What is the depression in freezing point (K_(f) for water = 1.86 kg "mole"^(-1)) (C = 12, O = 16, H = 1 g/mol).

Answer»

2.25 K
22.5 K
3.25 K
32.5 K

Solution :M.F `= C_(2)H_(6)O_(2)`
M.wt `= 2(12)+6(1)+2(16)`
`= 62 g mol^(-1)=M_(2)`
Weight of ETHYLENE glycol = 45 g `= W_(2)`
Weight of solvent (water = 600 g `= W_(1)`
`K_(f)` (water) = 1.86 kg `mol^(-1)`
`Delta T = K_(f)m`
`= (K_(f)XX W_(2)xx1000)/(M_(2)xx W_(1))`
`= (1.86xx 45" gram" xx 1000)/(62 g mol^(-1)xx 600 " gram")`
= 2.25 K
92147.

4.5 g of PCl5 on vapourisation occupied a volume of 1700 mL at 1 atmosphere pressure and 227 °C temperature. Its degree of dissociation is

Answer»

0.0921
0.0091
0.921
None of these

Solution :Let the degree of dissociation be `alpha`, then
`PCl_(5)toPCl_(3)+Cl_(2)`
`(1-alpha)""alpha""alpha`
(M) Molecular weight of `PCl_(5)` = 31 + 5 `xx` 35.5 = 208.5
Total number of MOLECULES before dissociation= 1
Total number of molecules after dissociation
`=1-alpha+alpha+alpha=1+alpha`
THUS each gram mole changes to (1 + a) gram-mole.
Thus `PV=W/M(1+alpha)RT`
( V = volume after dissociation)
or `1xx1700/1000=(4.5)/(208.5)(1+alpha)RT` [1700ml`=1700/1000L`]
or `alpha=0.921`
`therefore%` age dissociation =92.1%
92148.

4.5 gm of aluminium (atomic mass 27 amu) get deposited on cathode by passing fixed amount of electricity through Al^(3+) solution. So what is the volume of hydrogen gas at STP by passing same amount of electricity through H^(+) solution.

Answer»

44.8 L
22.4 L
11.2 L
5.6 L

Solution :NUMBER of grams in equivalence of `H^(+)`=Number of grams in equivalence of `Al^(3+)`
EQUIVALENT weight of `Al^(3+)=(27)/(3)=9`
`Al^(3+)=(4.5)/(9)=0.5`
Number of grams in equivalence of `H^(+)`=number of moles of `H^(+)`
So, equivalent weight of `H^(+)=0.5xx1.0gm`
`=0.5gm` of `H_(2)`
As we know that, 2 gm `H_(2)` at STP=22.4 L
So, at STP, 0.5 gm `H_(2)=(22.4)/(2)xx0.5=5.6L`
92149.

45 g of ethylene glycol (C_(2)H_(6)O_(2)) is mixed with 650 g of water. The freezing point depression (in K) will be (K_(f)"for water "=1.86 "K kg mol"^(-1)).

Answer»

Solution :Molality of solution (m)
`=("No of moles of "C_(2)H_(6)O_(2))/("Mass of water in kg")`
`=(((45G))/((62" G mol"^(-1))))/(6.65kg)=((0.73 mol))/((0.65kg))=1.12"mol kg"^(-1)`
`DeltaT_(f)=K_(f)xxm=(1.86" K kg mol"^(-1))xx(1.12 "mol kg"^(-1))`
`=2.08 K~~2K.`
92150.

4.5 g of PCl_(5)on vapourisation occupied a volume of 1700mL at atmosphere pressure and 227°C temperature. Calculate it: degree of dissociation.

Answer»


Solution :Let the degree of dissociation be `alpha`, then
`underset(1-alpha)(PCl_(5)) to underset(alpha)(PCl_(3)) + underset(alpha)(Cl_(2))`
(M) MOLECULAR weight of `PCl_(5) = 31+5 xx 35.5 = 208.5`
Total number of molecules before dissociation = 1 Total number of molecules ALTER dissociation
`=1- alpha + alpha + alpha =1 + alpha`
Thus each gram mole CHANGES to `(1+ alpha)` gram-mole.
Thus, `PV =W/M (1+alpha) RT`
(V = Volume after dissociation)
or `1 xx 1700/1000 = 4.5/(208.5) (1+ alpha) RT [1700 ml = 1700/1000 L]`
or `alpha = 0.921`