HSC Chemistry 1st Paper Model Question-5

Time : 3 hrs.                                                                                                                                Marks. 75

Group - A

1.         a)         What are fundamental particles? Describe three permanent fundamental particles.         1+3=4

            b)         What is quantum number? For complete description of an electron quantum number is        

            needed explain.                                                                                                                    1+3=4

            c)         Write the postulates of Bahr's atom model? What limitations are seen in Bahr's theory?  2+2=4

            d)         At constant temperature 200ml Hydrogen gas at pressure 1 atm and 400 ml oxygen gas at

            pressure of 600 mm ( Hg) are mixed in a flask of the volume of 1 litre. Calculate the total pressure

            of the mixtured gas.                                                                                                                               3

Or,       a)         State the Dalton's law of partial pressure and deduce its mathematical equation.                                    4

            b)         State the charle's law. Show that a new scale of measuring temperature is obtained from Charle's law.

            c)         Write down four differences between nuclear reaction and chemical reaction.                                   4

            d)         First 15 ml NaOH solution is partially neutralized 10 ml  0.1m HCl solution, but for complete             neutralization is requires more 6 ml of 0.15m HCl solution. What is the strength of Na OH solution?            3

2.         a)         What is order of reaction?  A      B, deduce mathematical expression of rate constant of this  type of             reaction.                                                                                                                                               4

            b)         What do you mean by molal solution and moral solution? Which one of these solutions is

            not depend on temperature and why?                                                                                           2+2=4

            c)         Discuss the classification of elements in light of electronic configuration.                              4

            d)         1.92 gm graphite pencil is need for 225 signature?  Calculate the number of carbon atom

            to complete one signature.                                                                                                                   3

Or,       a)         What is dry cell? Describe the construction and working principle of a dry cell.                                  4

            b)         Write down the differences between empirical and molecular formula?                                             4

            c)         What is the unit cell of crystal? Describe the crystalline structure of sodium chloride with diagram.   4

            d)         320 seconds is required for a first order reaction to decompose half of its initial state.

            What would be the time when one eighth of the substance of the reaction will remain.                                  3

3.         a)         What do you mean by ionic bond? explain with example, how this bond is formed?             4

            b)         What is ionization energy? How does it vary in same period and group in periodic table?                  4

            c)         What is Le-chalier's principle? Discuss the effect of temperature and pressure on the following             reaction. in the light of this principle.

                        N₂ ( g)  + 3 H₂ (g)              2 NH₃ (g)  + 92 Kg mol

            d)         25 cm³ of a KMnO₄ solution is required to oxidize 35 cm³ of  0.03 H₂ O₂ in presence of

            dilute H₂ SO₄. Determine the molar concentration of used KMnO₄ solution.                                      3

           

Or,       a)         Describe the concepts of acids and bases.                                                                                4

            b)         What is solubility product and ionic product? How the P^H scale are found from ionic product of water.

            c)         What do you man by oxidation potential and reduction potential? Potential of a standard     

            hydrogen electrode is zero explain,                                                                                                     4

            d)         25 ml of 0.05 m H₂ SO₄ solution is taken in a bicker and so on added 30 ml distilled

            water to this solution. What will be P^H of the H₂ SO₄ solution after adding mentioned amount of water?       3

4.         a)         What is SP³ hybridization?                                                                                                      3

            b)         What do you mean by mole? Explain with example.                                                               2

Or,       a)         2d and 3d orbitals are possible or not explain.                                                                                     3

            b)         What do you mean by delocalized P electron?                                                                                   2           

5.         a)         Describe the Farradays law of electrolysis.                                                                              3

            b)         What happens when Magnesium nitrate is heated.                                                                   2

Or        a)         Mention three main defects of modern periodic table.                                                             3

            b)         Graphite conduct electricity but diamond can not why - explain.                                                        2

6.         a)         Calculate the charge of a electron from Farrady's Law?                                                                      3

            b)         Semi Molar solution is a standard solution- explain.                                                               2

Or,       a)         Complete the following reactions.

                        (i)   Kr+ 3       ii)       iii)   Mg₃ N₂ + H₂O               ?

            b)         What is the acidity of Al₂ O₃ and why?                                                                                   2

7.         a)         What are the differences between orbital and orbit?                                                                3

            b)         How can you detect Ca²⁺ ion in solution?                                                                              2

Or,       a)         Electrons are transferred in oxidation and reduction reaction explain with proper example? 3

            b)         Explain that PbO is an amphoteric oxide.                                                                                2

8.         a)         The a aqueous solution of Al₂ (SO4)₃ is acidic explain.                                                                      3

            b)         Why concentrated HCl is use in flame test?                                                                             2

Or,       a)         PCl₅ is formed but NCl₅ is not formed -Why?                                                                         3

            b)         Write two uses of ideal gas equation.                                                                                       2

9.         a)         Can the value of equilibrium constant Ke be Zero or infinite even? Write reasons behind

            the answer.                                                                                                                                          3

            b)         Write down the formula of Borax and salt petre.                                                                                 2

Or,       a)         Corrosion of metal is a chemical process explain.                                                                   3

            b)         What do you mean by STP and SATP?                                                                                                2