Download SGBAU BSc 2019 Summer 4th Sem Chemistry Question Paper

FirstRanker.com
A Firstranker's choice

FirstRanker.com

--- Content provided by FirstRanker.com ---

AW-1712

B.Sc. Part-IT (Semester-1V) Examination

48 : CHEMISTRY

Time : Three Hours | [Maximum Marks : 80

Note :— (1) ALL questions are compulsory.

--- Content provided by FirstRanker.com ---

(2) Question No. 1 carries 8 marks while remaining SIX questions carry 12 marks each.

(3) Draw diagrams, write equations wherever necessary.

(4) Use of scientific calculator is allowed.

1. (A) Fill in the blanks :
   1. In Lanthanides, differentiating electron is added to __ subshell.
   2. The organic compounds containing two or more benzene nuclei in their structure are called .

   --- Content provided by FirstRanker.com ---

   3. Disaccharides on hydrolysis gives ~ units of monosaccharides.
   4. The temperature at which the liquid and the solid states of the substance have the same vapour pressure is called as .
   (B) Choose the correct alternative :
   1. Which of the following elements have Sd electrons in its electronic configuration: ?
      1. Pm
      2. Sm
      3. Eu

      --- Content provided by FirstRanker.com ---

      4. Gd
   2. Which of the following actinide does not occur in nature ?
      1. Th
      2. U
      3. Am

      --- Content provided by FirstRanker.com ---

      4. Pa
   3. Strecker synthesis is used for the synthesis of :
      1. Nitrobenzene
      2. Diazonium Salt
      3. o-amino acid

      --- Content provided by FirstRanker.com ---

      4. Carbohydrates
   4. NaCl is a example of :
      1. FCC
      2. BCC
      3. SCE

      --- Content provided by FirstRanker.com ---

      4. None of the above
   (C) Answer in ONE sentence each
   1. Define Paramagnetism.
   2. In metallurgy, what does the term gangue stand for ?
   3. Draw the structure of Malonic Ester (Diethyl Malonate).

   --- Content provided by FirstRanker.com ---

   4. Define Catalyst.

FirstRanker.com

2. (A) (i) Explain with suitable reasons electronic configuration of chromium is 3d⁵ 4s¹ instead of 3d⁴ 4s². (ii) Transition elements cannot form ionic compound in higher oxidation state. (B) What are transition elements ? Why Zn is not considered as a true transition element ? (C) What are the factors influencing the choice of extraction process ?
   OR
   

   --- Content provided by FirstRanker.com ---

   (P) Give the electronic configuration of : (i) Yttrium (atomic no. = 39) (ii) Silver (atomic no = 47). (Q) What are complexes ? Why 3d elements generally form complex ? (R) Which method would be applicable for separation of Na from NaCl and why ?
3. UNIT—II (A) Discuss the magnetic properties of Lanthanides. (B) Give the comparison of Lanthanides and Actinides. (C) Describe the process of Smelting
   OR
   (P) What is meant by Lanthanide contraction ? Explain in brief. (Q) Discuss the electrolytic refining of metals. (R) What are actinides ? Discuss the electronic configuration of actinides.
4. UNIT—III (A) Discuss the structure of Naphthalene. (B) How will you synthesize (i) 4-methyl uracil from AAE (ii) Succinic acid from malonic ester ? (C) What are epimers ? How will you convert D-Glucose into D-Mannose ?
   

   --- Content provided by FirstRanker.com ---

   OR
   (P) How will you convert : (i) AAE into propionic acid (ii) Acetic acid into malonic ester ? (Q) How will you bring out the following conversions : (i) o-naphthol to a-naphthyl amine (ii) B-naphthyl sulphonic acid to B-naphthol ? (R) Draw the structure of following compounds : (i) Maltose (ii) 2-Deoxy-D-Ribose.
5. UNIT—IV (A) What are a-amino acids ? Discuss structure determination of polypeptide by Sanger’s method. (B) Complete the following reaction :
   (C) Explain Hoffmann’s exhaustive methylation reaction.
   OR
   

   --- Content provided by FirstRanker.com ---

6. (P) Discuss the reduction of nitrobenzene in acidic and neutral medium. (Q) Complete the following reaction and predict the product :
   (R) How will you synthesize peptide from amino acid ?
7. UNIT—V (A) How Vant Hoff’s factor is used to determine the degree of dissociation of an electrolyte ? (B) Describe Cottrells” method for determination of elevation of boiling point. (C) Find molal elevation constant of water which evaporates at 373 K with absorption of 40658 J mol^-1 heat energy (R = 8.314 Jk^-1 mol^-1)
   OR
   

   --- Content provided by FirstRanker.com ---

8. (P) What are colligative properties ? Give the reasons for abnormal colligative properties. (Q) Derive the equation for Van’t Hoff’s factor when the solute undergoes association. (R) Calculate the molal depression constant of water. The heat of fusion of ice at 273 K is 6024.6 J mol^-1. (R = 8.314 Jk^-1, M = 18 x 10^-3 kg mol ^-1)
9. UNIT—VI (A) Differentiate between crystalline solids and amorphous solid. (B) Explain the structure of KCl on the basis of X-ray diffraction. (C) The first order reflection maxima was noted at 5.90 for 100 planes of SCC. Calculate wavelength of X-rays. if interplanar spacing was 0.282 nm.
   OR
   

--- Content provided by FirstRanker.com ---

10. (P) Explain with diagram : (i) Plane of symmetry (ii) Point of symmetry. (Q) Determine the number of constituent particles in the Face Centered Cubic (FCC) Unit Cell, Simple Cubic Crystal (SCC) Unit Cell. (R) Find out the Miller indices if Weiss indices are as follows : (i) 1:∞:∞ (ii) 2:2:3

FirstRanker.com