PAPER CODE- 6481
(11th CLASS-12014)
CHEMISTRY
(NEW COURSE)
TIME: 20 MINUTES
GROUP FIRST
MARKS: 17
OBJECTIVE
NOTE: You have four choices fax each objective type question as A,B C and D The choice which you think is correct , fill that circle in front of that question number, Use marker or pen to fill the circles, Cutting or filling two or more circles will result in zero mark in that question,

Question#1

• Tin has Isotopes
  
  (A) 9
  (B) 10
  (C) 11
  (D) 12
  
  
• The volume occupied by 1.4 g of N₂ at S.T.P is
  
  (A) 2.24 dm³
  (B) 22.4 dm³
  (C) l.12 dm³
  (D) 112 Cm³
  
  
• The drying agents used in desicator is
  
  (A) BeC1₂
  (B) MgCl₂
  (C) CaCl₂
  (D) SrC1₂
  
  
• During chromatography strip should be dipped in to solvent nurture to a depth of
  
  (A) 3—4mm
  (B) 4—5mm
  (C) 5—6 mm
  (D) 6—7mm
  
  
• Partial pressure of oxygen in the air
  
  (A) 156 torr 
  (B) 157 torr
  (C)158 torr
  (D) 159 torr
  
  
• The molar volume of CO₂ is maximum, at
  
  (A) STP
  (B) 127 °C and 1 atom
  (C) 0 °C and 2 atom
  (D) 273 °C and 2 atom
  
  
• If a=b=c and α=γ=90 °β= 90° then crystal system is
  
  (A) Monoclinic
  (B) Diclinic
  (C) Triclinic
  (D) Poly clinic
  
  
• Ionic solids are characterized by
  
  (A) Low melting points
  (B) good conductivity in solid state
  (C) High vapour pressure
  (D) Solubility in polar solvents
  
  
• De. Broglie equation is represented by
  
  (A) h=λ/mv
  (B) m = h/ λv
  (C) m= λ/hv
  (D) λ = h/mv
  
  
• Splitting of spectral lines when atoms are subjected to strong electric field is called
  
  (A) Zeeman effect
  (B) Stark effect
  (C) photoelectric effect
  (D) Compton effect
  
  
• The number of bonds in Nitrogen Molecule is
  
  (A) One σ and one π
  (B) One σ and two n
  (C) Three sigma only
  (D) two sigma and one π
  
  
• Dipole Moment of H₂O is
  
  (A) 1.61 D
  (B) 1.85 D
  (C) 0.95 D
  (D) 1.49 D
  
  
• The net heat change in a chemical reaction is same whether it is brought about in one step or through several steps, It is known as:
  
  (A) Henry's law
  (B) Boyle's law
  (C) Hess's law
  (D) Graham's law
  
  
• The pH of 10^-3 mol dm^-3 of an equeous solution of H₂SO₄ is:
  
  (A) 3.0
  (B) 2.7
  (C) 2.0
  (D) 1.5
  
  
• A solution of glucose is 10 % WN the volume in which 1 g mole of it is dissolved will be
  
  (A) I dm³
  (B) 1.8,dm ³
  (C) 200 Cm³
  (D) 900 Cm³
  
  
• If a strip of Cu metal is placed in a solution of FeSO₄
  
  (A) Cu will be deposited
  (B) Fe is precipitated out
  (C) Cu and Fe both dissolve
  (D) No reaction take place
  
  
• The unit of the rate constant is same as that of the rate of reaction in
  
  (A) First order reaction
  (B) Second order reaction
  (C) Zero order reaction
  (D) Third order reaction

CHEMISTRY
(NEW COURSE)
TIME: 3:10MINUTES
SUBJECTIVE

 2. Write short answers any Eight (8) questions of the following 16

• What is a molecular ion? Give two examples
• Why in experimental work one or more reactants is/are deliberately used in excess quantity
• Define molecular formula. How is it related to the empirical formula?
• Write down We uses of chromatography
• How undesirable colours are separated from a crude substance.
• Justify the change in the position of a straight line obtained when a graph is plotted between liv on x-axis and pressure P on the y-axis for a gas at two different temperatures
• Why normal air cannot be used for breathing by sea divers
• What is meant by the terms critical temperature and critical pressure?
• The boiling point of water is different at Murree hills and at Mount Everest. Justify it
• What are crystallographic elements?
• Why the electrical conductivity of metals decrease by increasing temperature
• Ethyl alcohol can dissolve in water but hydrocarbons are not soluble in water. Justify it.

3. Write short answers any Eight (8) questions of the following 16

• Give electronic configuration of an element having atomic number 24.
• Describe Hund's rule
• How positive rays are produced
• Give the drawbacks of Rotherford's atomic model
• By the bond distance is the compromise distance between two atoms ?
• The abnormality of bond length and bond strength in 1-11 is less prominent than that of HC1, Why?
• Why the bond angles in 1120 and NH3 are different , although 0 and N atoms are SP' hybridized
• The distinction between a co-ordinate covalent bond and a covalent bond vanishes after bond formation in NH₄.Why ?
• Which type of reactions is non-spontaneous? Give an example.
• Why is it necessary to mention the physical states of reactants and products in the thermo chemical reaction
• Why the solubility of glucose increases on increasing temperature 7
• Give two applications of buffer solution

4. Write short answers any Six (6) questions of the following 12

• Define reversible reaction with an example.
• What is molality ? Give its formula
• Give two examples of liquid-liquid solution.
• Define azeotropic mixture with example
• Define oxidation number, what is the oxidation number of elements in free state?
• Write down the equations for electrode processes in the electrolysis of fused PbCl₂
• Mention the function of salt bridge.
• Define the rate of reaction
• What is catalyst and what is catalysis?

SECTION.II

 Note: Attempt any Three questions from this section 8x3=24
Question#5
(a) Explain Isotopes with their relative abundance
(b) Explain seven crystal system with angles and edges

Question#6
(a) Write down the postulates of VSEPR Theory , illustrate with the explanation of the structure of one molecule
(b) Define and, explain Hess's law of constant heat summation with two examples.

Question#7
(a) One mole of methane gas is maintained at 300 K. Its volume. is 250 Cm³, Calculate its pressure considering it behaves, ideally.
(b) Describe Millikan's oil drop method for the measurement of charge on an electron.

Question#8
(a) State rules for assigning oxidation number of elements with examples.
(b) The solubility of PbF₂ at 25⁰C is 0.64 gdm^-3.Calculate K_sp of PbF₂(Atomic mass of Pb= 207.2 atomic mass of F=19)

Question#9
(a) What are a zeotropie mixtures , Explain with the help of graph
(b) Derive Arrhenius equation

SECTION-II

NOTE (i) Attempt any three parts from A,B,C,D and E 5x3 =15 (i) Write down standard solution, chemical equation with mole ratio , indicator with end point procedure and supposed reading with calculations for Part B and C (1+1 +1+1+1) (ii) Write down material required, diagram and procedure for part D and E (1+1+3)

Question#10
(A) 10 g of impure MOH has been dissolved per dm3 of solution. Calculate percentage purity of the sample (Molar mass of NaOH = 40)
(B) 39.2 g of FeSO₄. (NE₄)₂SO₄ . x H₂0 has been dissolved per dm³ of solution, calculate the value 'x. Molar mass of FeSO₄(NH₄)₂S0₄ . x H₂O= (284+ 18)
(C) 30 g of impure Na₂S₂0₃ 5H₂0 has been dissolved per dm³of solution. Find out percentage purity of samle (Molar Mass of Na₂S₂0₃ .5 H₂O=248)
(D) Separate the mixture of inks by paper chromatography
(E) Purify commercial NaC1 by passing ECI gas through common ion effect