46295 + Interview Questions in Chemistry

1.	In the purification of NaCl, impure solution is saturated with HCl gas. The principle involved is
Answer» In the purification of NaCl, impure solution is saturated with HCl gas. The principle involved is

Discussion

2.	What are the essentials or required qualities of a sample?
Answer» What are the essentials or required qualities of a sample?

Discussion

3.	Which of the following procedures would be best for achieving following reaction?
Answer» Which of the following procedures would be best for achieving following reaction?

Discussion

4.	In the reaction sequence, C6H5CHONH2OH/H+−−−−−−−−→△(X)P2O5−−−→△(Y)H2O/H+−−−−−→(Z) X, Y and Z respectively are:
Answer» In the reaction sequence, $C_{6} H_{5} C H O N H_{2} O H / H^{+} - ------- \to △ (X) P_{2} O_{5} - -- \to △ (Y) H_{2} O / H^{+} - ---- \to (Z)$ $X$ , $Y$ and $Z$ respectively are:

Discussion

5.	A reagent that brings an electron pair is known as:
Answer» A reagent that brings an electron pair is known as:

Discussion

6.	If the co-ordination number of Ca2+ in CaF2 is 8, then the coordination number of F− ion would be:
Answer» If the co-ordination number of $C a^{2 +}$ in $C a F_{2}$ is 8, then the coordination number of $F^{-}$ ion would be:

Discussion

7.	It is found that the equilibrium constant increases by a factor of four when the temperature is increased from 27 ∘C to 47 ∘C. The value of ΔH∘ is: Take ln2=0.7, log2=0.3, R=253 J mol−1 K−1
Answer» It is found that the equilibrium constant increases by a factor of four when the temperature is increased from $27^{\circ} C$ to $47^{\circ} C$ . The value of $Δ H^{\circ}$ is: Take $l n 2 = 0.7, l o g 2 = 0.3, R = \frac{25}{3} J m o l^{- 1} K^{- 1}$

Discussion

8.	The orbital angular momentum of an electron in s orbital is
Answer» The orbital angular momentum of an electron in s orbital is

Discussion

9.	Consider the following values of IE(ev) for elements W and X:- ElementIE1IE2IE3IE4W10.515.524.979.8X814.878.9105.8 Other two elements Y and Z have outer electronic configuration ns2np4 and ns2np5 respectively. According to given information which of the following compound (s) is/are not possible. (A)W2Y3(B)X2Y3(C)WZ2(D)XZ2
Answer» Consider the following values of IE(ev) for elements W and X:- $\begin{matrix} E l e m e n t & I E_{1} & I E_{2} & I E_{3} & I E_{4} W & 10.5 & 15.5 & 24.9 & 79.8 X & 8 & 14.8 & 78.9 & 105.8 \end{matrix}$ Other two elements Y and Z have outer electronic configuration $n s^{2} n p^{4}$ and $n s^{2} n p^{5}$ respectively. According to given information which of the following compound (s) is/are not possible. $(A) W_{2} Y_{3} (B) X_{2} Y_{3} (C) W Z_{2} (D) X Z_{2}$

Discussion

10.	Which molecule is T-shape?
Answer» Which molecule is T-shape?

Discussion

11.	In the following reaction, X is:
Answer» In the following reaction, X is:

Discussion

12.	Which of the following is an electrophilic addition reaction ?
Answer» Which of the following is an electrophilic addition reaction ?

Discussion

13.	When H2S gas is passed through a hot acidic aqueous solution containing Al3+,Cu2+,Pb2+ andNi2+, a precipitate is formed which consists of
Answer» When $H_{2} S$ gas is passed through a hot acidic aqueous solution containing $A l^{3 +}, C u^{2 +}, P b^{2 +} a n d N i^{2 +}$ , a precipitate is formed which consists of

Discussion

14.	The existence of a substance in more than one solid modifications is known asor Any compound having more than two crystal structures is called[MP PMT 1993; MP PET 1999]
Answer» The existence of a substance in more than one solid modifications is known as or Any compound having more than two crystal structures is called [MP PMT 1993; MP PET 1999]

14.

The existence of a substance in more than one solid modifications is known asor Any compound having more than two crystal structures is called[MP PMT 1993; MP PET 1999]

Answer»

The existence of a substance in more than one solid modifications is known as

or Any compound having more than two crystal structures is called

[MP PMT 1993; MP PET 1999]

Discussion

15.	For one mole of a Van der Waals gas when b=0 and T=300 K, the PVvs.1/V plot is shown below. The value of the Van der Waals constant a (atm L2 mol−2):
Answer» For one mole of a Van der Waals gas when $b = 0$ and $T = 300 K$ , the $P V v s . 1 / V$ plot is shown below. The value of the Van der Waals constant $a (a t m L^{2} m o l^{- 2}) :$

Discussion

16.	When ethylamine reacts with methyl magnesium bromide, the product is
Answer» When ethylamine reacts with methyl magnesium bromide, the product is

Discussion

17.	In a solid ‘AB’ having the NaCl structure, ‘A’ atoms occupy corners of the cube of unit cell. If all the face centered atoms along one axes are removed, then, the stiochiometry of the resultant crystal is
Answer» In a solid ‘AB’ having the NaCl structure, ‘A’ atoms occupy corners of the cube of unit cell. If all the face centered atoms along one axes are removed, then, the stiochiometry of the resultant crystal is

Discussion

18.	For the given reaction : Major product (Y) is :
Answer» For the given reaction : Major product (Y) is :

Discussion

19.	The concentration of sulphide ion in 0.1M HCl solution saturated with hydrogen sulphide is 1.0×10−19M. If 10 mL of this is added to 5 mL of 0.04 M solution of the following: FeSO4,MnCl2,ZnCl2 and CdCl2. in which of these solutions precipitation will take place? Given KspforFeS=6.3×10−18.MnS=2.5×10−13.ZnS=1.6×10−24.CdS=8.0×10−27
Answer» The concentration of sulphide ion in 0.1M HCl solution saturated with hydrogen sulphide is $1.0 \times 10^{- 19} M$ . If 10 mL of this is added to 5 mL of 0.04 M solution of the following: $F e S O_{4}, M n C l_{2}, Z n C l_{2}$ and $C d C l_{2}$ . in which of these solutions precipitation will take place? Given $K_{s p} f o r F e S = 6.3 \times 10^{- 18} . M n S = 2.5 \times 10^{- 13} . Z n S = 1.6 \times 10^{- 24} . C d S = 8.0 \times 10^{- 27}$

19.

The concentration of sulphide ion in 0.1M HCl solution saturated with hydrogen sulphide is 1.0×10−19M. If 10 mL of this is added to 5 mL of 0.04 M solution of the following: FeSO4,MnCl2,ZnCl2 and CdCl2. in which of these solutions precipitation will take place? Given KspforFeS=6.3×10−18.MnS=2.5×10−13.ZnS=1.6×10−24.CdS=8.0×10−27

Answer»

The concentration of sulphide ion in 0.1M HCl solution saturated with hydrogen sulphide is $1.0 \times 10^{- 19} M$ . If 10 mL of this is added to 5 mL of 0.04 M solution of the following:
$F e S O_{4}, M n C l_{2}, Z n C l_{2}$ and $C d C l_{2}$ . in which of these solutions precipitation will take place?

Given $K_{s p} f o r F e S = 6.3 \times 10^{- 18} . M n S = 2.5 \times 10^{- 13} . Z n S = 1.6 \times 10^{- 24} . C d S = 8.0 \times 10^{- 27}$

Discussion

20.	Why is zinc not extracted from zinc oxide through reduction using CO?
Answer» Why is zinc not extracted from zinc oxide through reduction using CO?

Discussion

21.	Given C(graphite)+O2(g)→CO2(g); ΔfH∘=−393.5 kJmol−1 H2(g)+12O2(g)→H2O(l) ΔfH∘=−285.8 kJmol−1 CO2(g)+2H2O(l)→CH4(g)+2O2(g) ΔfH∘=+890.3 kJmol−1 Based on the above thermochemical equations, the value of ΔfH∘ at 298 K for the reaction C(graphite)+2H2(g)→CH4(g) will be:
Answer» Given $C_{(g r a p h i t e)} + O_{2} (g) \to C O_{2} (g);$ $Δ_{f} H^{\circ} = - 393.5 k J m o l^{- 1}$ $H_{2} (g) + \frac{1}{2} O_{2} (g) \to H_{2} O (l)$ $Δ_{f} H^{\circ} = - 285.8 k J m o l^{- 1}$ $C O_{2} (g) + 2 H_{2} O (l) \to C H_{4} (g) + 2 O_{2} (g)$ $Δ_{f} H^{\circ} = + 890.3 k J m o l^{- 1}$ Based on the above thermochemical equations, the value of $Δ_{f} H^{\circ}$ at 298 K for the reaction $C_{(g r a p h i t e)} + 2 H_{2} (g) \to C H_{4} (g)$ will be:

Discussion

22.	Calculate the number of unit cells in 8.1 g of aluminium if it crystallizes in a face - centred cubic (fcc) structure. (Atomic mass of Al = 27 g mol−1)
Answer» Calculate the number of unit cells in 8.1 g of aluminium if it crystallizes in a face - centred cubic (fcc) structure. (Atomic mass of Al = 27 g $m o l^{- 1}$ )

Discussion

23.	The oxidizing power of the halogens varies in the order
Answer» The oxidizing power of the halogens varies in the order

Discussion

24.	The standard electrode potentials of Zn2+Zn and Ag+Ag are −0.763 V and +0.799 V respectively. The standard potential of the cell is
Answer» The standard electrode potentials of $\frac{Z n^{2 +}}{Z n}$ and $\frac{A g^{+}}{A g}$ are $- 0.763 V$ and $+ 0.799 V$ respectively. The standard potential of the cell is

Discussion

25.	In the hydrogenation of the following reaction the state of carbon changes from: C2H2 −−−→ C2H4 −−−→ C2H6
Answer» In the hydrogenation of the following reaction the state of carbon changes from: $C_{2} H_{2} - -- \to C_{2} H_{4} - -- \to C_{2} H_{6}$

Discussion

26.	Solution of (+) -2-chloro -2- phenylethane in toluene racemises slowly in the presence of small amount of SbCl5, due to the formation of
Answer» Solution of (+) -2-chloro -2- phenylethane in toluene racemises slowly in the presence of small amount of SbCl₅, due to the formation of

Discussion

27.	Which of the following will have hightest boiling point at 1 atm pressure?
Answer» Which of the following will have hightest boiling point at 1 atm pressure?

Discussion

28.	The vapour pressure of pure benzene and toluene are 160 and 60 torr respectively. The mole fraction of toluene in vapour phase in contact with the equimolar solution of benzene and toluene is
Answer» The vapour pressure of pure benzene and toluene are 160 and 60 torr respectively. The mole fraction of toluene in vapour phase in contact with the equimolar solution of benzene and toluene is

Discussion

29.	The compound in which Cl is assigned the lowest oxidation number is:
Answer» The compound in which Cl is assigned the lowest oxidation number is:

Discussion

30.	The transition element among the following is
Answer» The transition element among the following is

Discussion

31.	Adsorption is a phenomenon in which a substance:
Answer» Adsorption is a phenomenon in which a substance:

Discussion

32.	QUESTION 2.6 How many mL of 0.1 M HCl are required to react completely with 1 g mixture of Na2CO3 and NaHCO3 containing equimolar amounts of both?
Answer» QUESTION 2.6 How many mL of 0.1 M HCl are required to react completely with 1 g mixture of ${N a}_{2} C O_{3}$ and $N a H C O_{3}$ containing equimolar amounts of both?

32.

QUESTION 2.6 How many mL of 0.1 M HCl are required to react completely with 1 g mixture of Na2CO3 and NaHCO3 containing equimolar amounts of both?

Answer»

QUESTION 2.6

How many mL of 0.1 M HCl are required to react completely with 1 g mixture of ${N a}_{2} C O_{3}$ and $N a H C O_{3}$ containing equimolar amounts of both?

Discussion

33.	The root mean square velocity of a monoatomic gas (molar mass =m kg mol−1) is u. Its kinetic energy per mole (E) is related to u by equation:
Answer» The root mean square velocity of a monoatomic gas (molar mass $= m {kg mol}^{- 1}$ ) is $u$ . Its kinetic energy per mole $(E)$ is related to $u$ by equation:

Discussion

34.	Difference between △H and △U for the combustion of benzene at 300 K is
Answer» Difference between $△ H$ and $△ U$ for the combustion of benzene at $300 K$ is

Discussion

35.	Iodine is formed when potassium iodide reacts with:
Answer» Iodine is formed when potassium iodide reacts with:

Discussion

36.	The carbon reduction method is mainly applicable for the extraction of how many of the following metals? Sn,Al,Cr,Mn,Pb,Ca,Na,Zn
Answer» The carbon reduction method is mainly applicable for the extraction of how many of the following metals? $S n, A l, C r, M n, P b, C a, N a, Z n$

Discussion

37.	What are antistaling agents?
Answer» What are antistaling agents?

Discussion

38.	If 1 gram of carbon contains x atoms, what will be the number of atoms in 1 gram of magnesium?
Answer» If 1 gram of carbon contains x atoms, what will be the number of atoms in 1 gram of magnesium?

38.

If 1 gram of carbon contains x atoms, what will be the number of atoms in 1 gram of magnesium?

Answer»

If 1 gram of carbon contains x atoms, what will be the number of atoms in 1 gram of magnesium?

Discussion

39.	An organic compound contains carbon, hydrogen and oxygen. Its chemical analysis gave C,38.71% and H,9.67%. The empirical formula of compound would be
Answer» An organic compound contains carbon, hydrogen and oxygen. Its chemical analysis gave $C, 38.71 %$ and $H, 9.67 %$ . The empirical formula of compound would be

Discussion

40.	Write the equations for the following lab, preparations: a) Ethane from sodium propionate b) Ethane from iodoethane c) Ethyne from calcium carbide d) Methanol from iodomethane. [4 MARKS]
Answer» Write the equations for the following lab, preparations: a) Ethane from sodium propionate b) Ethane from iodoethane c) Ethyne from calcium carbide d) Methanol from iodomethane. [4 MARKS]

Discussion

41.	White phosphorous is a tetra atomic solid [P4(s)] at room temperature and on strong heating in absence of oxygen, it polymerizes into red phosphorus as: ΔH=−104 kJ/mol of P4 The enthalpy of sublimation [P4(s)→P4(g)] white is 59 kJ/mol and enthalpy of atomization is 316.25 kJ/mol of P(g). Now find the average P−P bond enthalpy in P4 molecule is:
Answer» White phosphorous is a tetra atomic solid $[P_{4} (s)]$ at room temperature and on strong heating in absence of oxygen, it polymerizes into red phosphorus as: $Δ H = - 104 kJ/mol of P_{4}$ The enthalpy of sublimation $[P_{4} (s) \to P_{4} (g)]$ white is $59 kJ/mol$ and enthalpy of atomization is $316.25 kJ/mol$ of $P (g)$ . Now find the average $P - P$ bond enthalpy in $P_{4}$ molecule is:

Discussion

42.	Is there any specific formula to find the number of chain isomers of an organic compound?
Answer» Is there any specific formula to find the number of chain isomers of an organic compound?

Discussion

43.	A sample of clay contains 50% silica and 10% water. The sample is partially dried by which it loses 8 g water. If the percentage of silica in the partially dried clay is 52, calculate the percentage of water in the partially dried clay ?
Answer» A sample of clay contains $50 %$ silica and $10 %$ water. The sample is partially dried by which it loses $8 g$ water. If the percentage of silica in the partially dried clay is $52$ , calculate the percentage of water in the partially dried clay ?

Discussion

44.	Are all 118 elements discovered
Answer» Are all 118 elements discovered

Discussion

45.	A metal crystallises into two cubic phases, fcc and bcc. These have unit cell lengths 3.5 and 3 angstrom respectively. Calculate the ratio of densities of fcc and bcc.
Answer» A metal crystallises into two cubic phases, fcc and bcc. These have unit cell lengths 3.5 and 3 angstrom respectively. Calculate the ratio of densities of fcc and bcc.

Discussion

46.	One mole of an ideal gas expands isothermally from initial state ( 1 atm, 22.4 L, 273 K ) to the final state (0.25 atm,89.6 L) in reversible manner. One mole of the same gas with the same initial state in a different cylinder expands against a constant external pressure of 0.25 atm to final volume 89.6 L. The difference in work done in J is (Take 1 L atm=101 J, R=8.3 J K−1 mol−1, log2=0.3)
Answer» One mole of an ideal gas expands isothermally from initial state ( 1 atm, 22.4 L, 273 K ) to the final state ( $0.25 a t m, 89.6 L$ ) in reversible manner. One mole of the same gas with the same initial state in a different cylinder expands against a constant external pressure of $0.25 a t m$ to final volume $89.6 L$ . The difference in work done in J is $(T a k e 1 L a t m = 101 J, R = 8.3 J K^{- 1} m o l^{- 1}, l o g 2 = 0.3)$

Discussion

47.	The density of a gas A is twice that of gas B at the same temperature. The molecular weight of gas B is twice that of gas A. The ratio of pressures of gases A and B will be:
Answer» The density of a gas $A$ is twice that of gas $B$ at the same temperature. The molecular weight of gas $B$ is twice that of gas $A$ . The ratio of pressures of gases $A$ and $B$ will be:

Discussion

48.	A beaker contains 0.1 M H2SO4 solution; of 100 ml. Another 100 ml, 0.1 M HCl of it is added to the beaker. (I) What is the initial number of millimoles of H+ ions? (II) What is the final concentration of H+ ions?
Answer» A beaker contains 0.1 M $H_{2} S O_{4}$ solution; of 100 ml. Another 100 ml, 0.1 M $H C l$ of it is added to the beaker. (I) What is the initial number of millimoles of $H^{+}$ ions? (II) What is the final concentration of $H^{+}$ ions?

Discussion

49.	Among the following pairs of orbitals which orbital will experience the larger effective nuclear charge? (i) 2s and 3s, (ii) 4d and 4f (iii) 3d and 3p
Answer» Among the following pairs of orbitals which orbital will experience the larger effective nuclear charge? (i) 2s and 3s, (ii) 4d and 4f (iii) 3d and 3p

49.

Among the following pairs of orbitals which orbital will experience the larger effective nuclear charge? (i) 2s and 3s, (ii) 4d and 4f (iii) 3d and 3p

Answer»

Among the following pairs of orbitals which orbital will experience the larger effective nuclear charge?
(i) 2s and 3s,

(ii) 4d and 4f

(iii) 3d and 3p

Discussion

50.	The electron gain enthalpy of oxygen atom is 1.41×105Jmol−1. Energy required (in kJ) to oxidise 4 g of O− ions into oxygen atom is
Answer» The electron gain enthalpy of oxygen atom is $1.41 \times 10^{5} J m o l^{- 1}$ . Energy required $(i n k J)$ to oxidise 4 g of $O^{-}$ ions into oxygen atom is

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

In the purification of NaCl, impure solution is saturated with HCl gas. The principle involved is

What are the essentials or required qualities of a sample?

Which of the following procedures would be best for achieving following reaction?

In the reaction sequence, C6H5CHONH2OH/H+−−−−−−−−→△(X)P2O5−−−→△(Y)H2O/H+−−−−−→(Z) X, Y and Z respectively are:

A reagent that brings an electron pair is known as:

If the co-ordination number of Ca2+ in CaF2 is 8, then the coordination number of F− ion would be:

It is found that the equilibrium constant increases by a factor of four when the temperature is increased from 27 ∘C to 47 ∘C. The value of ΔH∘ is: Take ln2=0.7, log2=0.3, R=253 J mol−1 K−1

The orbital angular momentum of an electron in s orbital is

Which molecule is T-shape?

In the following reaction, X is:

Which of the following is an electrophilic addition reaction ?

When H2S gas is passed through a hot acidic aqueous solution containing Al3+,Cu2+,Pb2+ andNi2+, a precipitate is formed which consists of

The existence of a substance in more than one solid modifications is known asor Any compound having more than two crystal structures is called[MP PMT 1993; MP PET 1999]

For one mole of a Van der Waals gas when b=0 and T=300 K, the PVvs.1/V plot is shown below. The value of the Van der Waals constant a (atm L2 mol−2):

When ethylamine reacts with methyl magnesium bromide, the product is

In a solid ‘AB’ having the NaCl structure, ‘A’ atoms occupy corners of the cube of unit cell. If all the face centered atoms along one axes are removed, then, the stiochiometry of the resultant crystal is

For the given reaction : Major product (Y) is :

Why is zinc not extracted from zinc oxide through reduction using CO?

Given C(graphite)+O2(g)→CO2(g); ΔfH∘=−393.5 kJmol−1 H2(g)+12O2(g)→H2O(l) ΔfH∘=−285.8 kJmol−1 CO2(g)+2H2O(l)→CH4(g)+2O2(g) ΔfH∘=+890.3 kJmol−1 Based on the above thermochemical equations, the value of ΔfH∘ at 298 K for the reaction C(graphite)+2H2(g)→CH4(g) will be:

Calculate the number of unit cells in 8.1 g of aluminium if it crystallizes in a face - centred cubic (fcc) structure. (Atomic mass of Al = 27 g mol−1)

The oxidizing power of the halogens varies in the order

The standard electrode potentials of Zn2+Zn and Ag+Ag are −0.763 V and +0.799 V respectively. The standard potential of the cell is

In the hydrogenation of the following reaction the state of carbon changes from: C2H2 −−−→ C2H4 −−−→ C2H6

Solution of (+) -2-chloro -2- phenylethane in toluene racemises slowly in the presence of small amount of SbCl5, due to the formation of

Which of the following will have hightest boiling point at 1 atm pressure?

The vapour pressure of pure benzene and toluene are 160 and 60 torr respectively. The mole fraction of toluene in vapour phase in contact with the equimolar solution of benzene and toluene is

The compound in which Cl is assigned the lowest oxidation number is:

The transition element among the following is

Adsorption is a phenomenon in which a substance:

QUESTION 2.6 How many mL of 0.1 M HCl are required to react completely with 1 g mixture of Na2CO3 and NaHCO3 containing equimolar amounts of both?

The root mean square velocity of a monoatomic gas (molar mass =m kg mol−1) is u. Its kinetic energy per mole (E) is related to u by equation:

Difference between △H and △U for the combustion of benzene at 300 K is

Iodine is formed when potassium iodide reacts with:

The carbon reduction method is mainly applicable for the extraction of how many of the following metals? Sn,Al,Cr,Mn,Pb,Ca,Na,Zn

What are antistaling agents?

If 1 gram of carbon contains x atoms, what will be the number of atoms in 1 gram of magnesium?

An organic compound contains carbon, hydrogen and oxygen. Its chemical analysis gave C,38.71% and H,9.67%. The empirical formula of compound would be

Write the equations for the following lab, preparations: a) Ethane from sodium propionate b) Ethane from iodoethane c) Ethyne from calcium carbide d) Methanol from iodomethane. [4 MARKS]

Is there any specific formula to find the number of chain isomers of an organic compound?

A sample of clay contains 50% silica and 10% water. The sample is partially dried by which it loses 8 g water. If the percentage of silica in the partially dried clay is 52, calculate the percentage of water in the partially dried clay ?

Are all 118 elements discovered

A metal crystallises into two cubic phases, fcc and bcc. These have unit cell lengths 3.5 and 3 angstrom respectively. Calculate the ratio of densities of fcc and bcc.

The density of a gas A is twice that of gas B at the same temperature. The molecular weight of gas B is twice that of gas A. The ratio of pressures of gases A and B will be:

A beaker contains 0.1 M H2SO4 solution; of 100 ml. Another 100 ml, 0.1 M HCl of it is added to the beaker. (I) What is the initial number of millimoles of H+ ions? ​(II) What is the final concentration of H+ ions?

Among the following pairs of orbitals which orbital will experience the larger effective nuclear charge? (i) 2s and 3s, (ii) 4d and 4f (iii) 3d and 3p

The electron gain enthalpy of oxygen atom is 1.41×105Jmol−1. Energy required (in kJ) to oxidise 4 g of O− ions into oxygen atom is

A beaker contains 0.1 M H2SO4 solution; of 100 ml. Another 100 ml, 0.1 M HCl of it is added to the beaker. (I) What is the initial number of millimoles of H+ ions? (II) What is the final concentration of H+ ions?