CHEMISTRY-25-02- 11th (PQRS & J) Space
FINAL TEST
Class : XI
Time : 90 min. Max. Marks : 90
INSTRUCTIONS
General Remarks:
1. The question paper contain 15 questions and 24 pages. All questions are compulsory.
Please ensure that the Question Paper you have received contains all the QUESTIONS and Pages. If you found some mistake like missing questions or pages then contact immediately to the Invigilator.
2. Write your BC roll no. on top right corner of page #3 of answer sheet also.
3. Each question should be done only in the space provided for it, otherwise the solution will not be checked.
4. Use of Calculator, Log table and Mobile is not permitted.
5. Legibility and clarity in answering the question will be appreciated.
6. Put a cross ( × ) on the rough work done by you.
7. You can tear off the LAST PAGE carefully along the scissor marked line and take it as Final Test.
Name Father's Name
Class :
Batch :
B.C. Roll No.
Invigilator's Full Name
USEFUL DATA
Atomic Mass: Al = 27, Mg = 24, Cu = 63.5, Mn = 55, Cl = 35.5, O = 16, H = 1, P = 31,
Ag = 108, N = 14, Li = 7, I = 127, Cr = 52, K=39, S = 32, Na = 23, C = 12, Br = 80, Fe = 56, Ca = 40,
Zn = 65.4, Ba = 137, Co = 59, Hg = 200, Pb = 207, He = 4, F=19, Ar = 40
Radius of nucleus =10–14 m; h = 6.62 ×10–34 Js; me = 9.1 ×10–31 kg, RH = 109637 cm–1.
For Office Use ……………………………. Total Marks Obtained…………………
Q.No 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Marks
PART -A
Q.1 If % ionic character of O–H bond is 10% & O–H bond distance is
1
4.8
Å, then calculate dipole
moment of H2O molecule (in Debye) given H–O–H bond angle is 105°. [Use cos 52.5° = 0.6] [5]
BC Roll. No.
Q.2 Arrange in ascending order (reasons not required)
(a) | Hhydrogenation| of : 1, 2 Pentadiene, 1, 3 Pentadiene & 1, 4 Pentadiene
(b) Ionic conductance of aq. solution : Li+, Na+ & Cs+.
(c) Dipole Moment of : , , ,
(d) Boiling point : n-pentane, isopentane, neo-pentane [1.5+1+1.5+1]
Q.3 Balance the reaction
(a) Oxidation of cyclobutylmethanol to cyclobutane carboxylic acid by MnO– in acidic medium.
(b) Ca(OCl2) + KI + HCl I2 + CaCl2 + KCl [3+2]
Q.4
(a) Write the IUPAC name of [2]
(i) (ii)
(b) Predict the final product [2]
O
||
(i) CH3 CH2 C NH2
+ NaOH
H2O ? (ii)
+ NaOH
H2O ?
(c) Which transition in Be3+ emits same wavelength as the 2nd line of Balmer series of Hydrogen. [1]
(Z of Be = 4)
Q.5(a) Draw an Andrew's isotherm of a real gas for three temperatures (T > Tcritical, T = Tcritical, T < Tcritical) on a same graph. Highlight the liquifaction curve in it.
(b) Argon at a temperature of 273 K & pressure 1 atm has a density of (48/22.4) gm/lit. Predict whether it behaves ideally or acts as real. If real, then which Vander Waal constant is more influential. Why?
(Ar = 40, R = 0.0821 lt-atm/K-mol) [2+3]
Q.6(a) If internuclear distance between Cl atoms in Cl2 is 10 Å & between H atoms in H2 is 2 Å, then calculate internuclear distance between H & Cl (Electronegativity of H = 2.1 & Cl = 3.0). [2]
(b) Compare the following giving reasons
(i) Acidic nature of oxides: CaO, CO, CO2, N2O5, SO3
(ii) Bond length of P—O, S—O & Cl—O in PO3– , SO2– , ClO– respectively. [3]
4 4 4
PART -B
Q.7 A solution of Ba3(PO4)2 having molarity = 2M initially dissociates to give Ba2+ & PO43–. If extent of dissociation of salt is 75% & density of solution is 3.202 gm/ml, then calculate molality (m) of each of the specie. [Ba3(PO4)4, Ba2+ & PO43–] (Ba = 137, P = 31, O = 16) [6]
Q.8 A 116.4 mg sample of impure KSCN on reaction with KMnO4 give Mn2+, SO42– & CN–. All the
SO2–
produced was reacted with KI to give SO2 gas & I2 gas. I2 gas liberated required 10 ml of
0.1 M K2Cr2O7 solution to get converted to IO–
alongwith Cr3+. Write all the unbalanced skeleton
reactions. Calculate percent purity of KSCN sample & moles of KMnO4 required in first step.
(K = 39, S = 32, C = 12, N = 14) [6]
Q.9 A metal was subjected to electromagnetic radiations having varied frequency & a graph ofmaximum KE of ejected photon vs frequency was plotted. From the graph calculate
(a) Work function of the metal in eV/atom
(b) Possible range of KE (in eV) of ejected photoelectron if they are accelerated by a potential difference of
2 volt if of electromagnetic radiation is 20 nm.(h = 6.62 ×10–34 J-sec., E = 1240 eV nm ) [6]
Q.10 Suppose in the Bohr's model of H–atom, instead of electrostatic force, some other force is acting between
nucleus & electron which cause the potential energy to vary as
k . What should be the sign of k so that
5r5
electron can move in uniformcircular motionabout nucleus. Assuming quantization of angular momentum. Also derive expression for radius of nth orbit. [6]
Q.11 Three flasks of identical volume are connected through tubes of negligible volume with two valves both initially closed. Container I contains 1 mole H2, 2 mole O2 & 3 mole SO2 & all the containers are maintained at temperature T. Valve I is opened for a very long time (till movement of gases stop). Valve I is then closed & valve II is opened for a very short time (so that rate of effusion remains constant) & then closed again. Assuming that container II & III contained nothing initially. Answer the following questions.
(a) What is the number of moles in the two container I & II just before opening valve II ?
(b) What is the ratio of moles of each specie in container III after opening value II ? [2+4]
PART -C
Q.12 An organic compound contains 1 – OH group, 1 bond & 1 ketone group other than carbon and hydrogen. It is known that ' ' bond is non terminal & alcohol is a primary alcohol. 224 ml of the gaseous molecule at STP is exploded with unknown but excess amount of O2 and the resultant reaction caused a contraction of V ml at STP. The acidic gas obtained in the reaction was treated with excess of NaOH & the resultant solution was divided into two equal halves. One half required 35 ml of 1 N HCl using phenolphthalein indicator & other half required 60 ml of 1 N HCl using MeOH indicator. Using the above information answer the questions
(a) Predict the general formula of compound
(b) Predict the molecular formula of compound
(c) What will be the value of V ml (contraction due to combustion & cooling)
(d) Predict the possible structural formula(e) [1.5+3+1.5+1.5=7.5]
Q.13 An atomic orbital has radial wave function represented as
(r) ker / k' r2[(r2 5.5a0r 7a2)(r2 8.5a
0r 18a2)]
where k, k' & a0 are constants.
(a) How many radial nodes are present at what distance from the nucleus? (answer in terms of a0)
(b) Draw a radial probability distribution curve for the above orbital clearly highlighting the parameters which are being plotted & nodes & antinodes.
(c) In which period of periodic table does the first element with last electron in this orbital is expected to go. What will be the total number of elements which can be present in that period?
[4+1.5+2=7.5]
Q.14 Complete the missing data in the following graph.
(a) moles, n = 2, ideal gas subjected to a process in which P(atm) × 0.0821 = V (lit)
Calculate tan & C. (R = 0.0821 lt-atm/K-mol )
(b) Calculate slope & intercept of the graph if wt. of silver salt of succinic acid is plotted with wt. of silver residue obtained due to heating the silver salt.(Ag = 108) [4+3.5=7.5]
Q.15(a) Calculate H of the following reaction from the data (all in kJ/mole)
NH3 (g) + HCl (g) NH4Cl (s)
(i) H proton gain enthalpy of NH3 (s) = – 720
(ii) H bond dissociation of HCl (g) = 100
(iii) H ionization energy of H = 1300
(iv) H Electron gain enthalpy of Cl = – 350
(v) H lattice energy of NH4Cl (s) = – 700
(b) If 107 gm of a mixture containing NH3 (g) and HCl (g) is to be divided so as to obtain maximum amount of energy. What should be the wt. of each specie taken for this and what is the amount of energy.
(Cl = 35.5, H = 1, N = 14) [5+2.5]
PART -A
Q.1 If % ionic character of O–H bond is 10% & O–H bond distance is
1
4.8
Å, then calculate dipole moment of H2O
molecule (in Debye) given H–O–H bond angle is 105°. [Use cos 52.5° = 0.6] [5]
Q.2 Arrange in ascending order (reasons not required)
(a) | Hhydrogenation| of : 1, 2 Pentadiene, 1, 3 Pentadiene & 1, 4 Pentadiene
(b) Ionic conductance of aq. solution : Li+, Na+ & Cs+.
(c) Dipole Moment of : , , ,
4
(i) (ii)
(b) Predict the final product [2]
O
||
(i) CH3 CH 2 C NH2 + NaOH H2O ? (ii)
+ NaOH H2O ?
(c) Which transition in Be3+ emits same wavelength as the 2nd line of Balmer series of Hydrogen. [1]
(Z of Be = 4)
Q.5(a) Draw an Andrew's isotherm of a real gas for three temperatures (T > Tcritical, T = Tcritical, T < Tcritical) on a same graph.
Highlight the liquifaction curve in it.
(b) Argon at a temperature of 273 K & pressure 1 atm has a density of (48/22.4) gm/lit. Predict whether it behaves ideally or acts as real. If real, then which Vander Waal constant is more influential. Why?
(Ar = 40, R = 0.0821 lt-atm/K-mol) [2+3]
Q.6(a) If internuclear distance between Cl atoms in Cl2 is 10 Å & between H atoms in H2 is 2 Å, then calculate internuclear distance between H & Cl (Electronegativity of H = 2.1 & Cl = 3.0). [2]
(b) Compare the following giving reasons
(i) Acidic nature of oxides: CaO, CO, CO2, N2O5, SO3
(ii) Bond length of P—O, S—O & Cl—O in PO3– , SO2– , ClO– respectively. [3]
4 4 4
PART -B
Q.7 A solution of Ba3(PO4)2 having molarity = 2M initially dissociates to give Ba2+ & PO 3–. If extent of dissociation of salt is 75% & density of solution is 3.202 gm/ml, then calculate molality (m) of each of the specie. [Ba3(PO4)4, Ba2+ & PO 3–
] (Ba = 137, P = 31, O = 16) [6]
Q.8 A 116.4 mg sample of impure KSCN on reaction with KMnO give Mn2+, SO 2– & CN–. All the SO2– produced was
4 4 4
reacted with KI to give SO2 gas & I2 gas. I2 gas liberated required 10 ml of 0.1 M K2Cr2O7 solution to get converted
to IO–
alongwith Cr3+. Write all the unbalanced skeleton reactions. Calculate percent purity of KSCN sample &
moles of KMnO4 required in first step.
(K = 39, S = 32, C = 12, N = 14) [6]
Q.9 A metal was subjected to electromagnetic radiations having varied frequency & a graph of maximum KE of ejected photon vs frequency was plotted. From the
graph calculate
(a) Work function of the metal in eV/atom
(b) Possible range of KE (in eV) of ejected photoelectron if they are accelerated by a potential difference of 2 volt if of
1240
electromagnetic radiation is 20 nm. (h = 6.62 ×10–34 J-sec., E =
eV nm ) [6]
Q.10 Suppose in the Bohr's model of H–atom, instead of electrostatic force, some other force is acting between nucleus &
k
electron which cause the potential energy to vary as 5r5 . What should be the sign of k so that electron can move in
uniform circular motion about nucleus. Assuming quantization of angular momentum. Also derive expression for radius of nth orbit. [6]
Q.11 Three flasks of identical volume are connected through tubes of negligible volume with two valves both initially closed. Container I contains 1 mole H2, 2 mole O2 & 3 mole SO2 & all the containers are maintained at temperature T. Valve I is opened for a very long time (till movement of gases stop). Valve I is then closed & valve
II is opened for a very short time (so that rate of effusion remains constant) & then closed again. Assuming that container II & III contained nothing initially. Answer the following questions.
(a) What is the number of moles in the two container I & II just before opening valve II ?
(b) What is the ratio of moles of each specie in container III after opening value II ? [2+4]
PART -C
Q.12 An organic compound contains 1 – OH group, 1 bond & 1 ketone group other than carbon and hydrogen. It is known that ' ' bond is non terminal & alcohol is a primary alcohol. 224 ml of the gaseous molecule at STP is exploded with unknown but excess amount of O2 and the resultant reaction caused a contraction of V ml at STP. The acidic gas obtained in the reaction was treated with excess of NaOH & the resultant solution was divided into two equal halves. One half required 35 ml of 1 N HCl using phenolphthalein indicator & other half required 60 ml of 1 N HCl using MeOH indicator. Using the above information answer the questions
(a) Predict the general formula of compound (b) Predict the molecular formula of compound
(c) What will be the value of V ml (contraction due to combustion & cooling)
(d) Predict the possible structural formula(e) [1.5+3+1.5+1.5=7.5]
Q.13 An atomic orbital has radial wave function represented as (r) ker / k' r2[(r2 5.5a0r 7a2 )(r2 8.5a r 18a2 )]
where k, k' & a0 are constants.
0 0 0
(a) How many radial nodes are present at what distance from the nucleus? (answer in terms of a0)
(b) Draw a radial probability distribution curve for the above orbital clearly highlighting the parameters which are being plotted & nodes & antinodes.
(c) In which period of periodic table does the first element with last electron in this orbital is expected to go. What will be the total number of elements which can be present in that period? [4+1.5+2=7.5]
Q.14 Complete the missing data in the following graph.
(a) moles, n = 2, ideal gas subjected to a process in which P(atm) × 0.0821 = V (lit) Calculate tan & C. (R = 0.0821 lt-atm/K-mol )
(b) Calculate slope & intercept of the graph if wt. of silver salt of succinic acid is plotted
with wt. of silver residue obtained due to heating the silver salt.(Ag = 108)
[4+3.5=7.5]
Q.15(a) Calculate H of the following reaction from the data (all in kJ/mole) NH3 (g) + HCl (g) NH4Cl (s)
(i) H proton gain enthalpy of NH3 (s) = – 720
(ii) H bond dissociation of HCl (g) = 100
(iii) H ionization energy of H = 1300
(iv) H Electron gain enthalpy of Cl = – 350
(v) H lattice energy of NH4Cl (s) = – 700
(b) If 107 gm of a mixture containing NH3 (g) and HCl (g) is to be divided so as to obtain maximum amount of energy. What should be the wt. of each specie taken for this and what is the amount of energy. [5+2.5]
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