part-b

PART-B Choose the correct answer and write its letter in the brackets.   1.  Units of universal gravitational constant is             a)  m/sec2                   b)  N. m2/kg2                c)  N.m2. kg2                d)  m.sec2         [        ] 2.  For a freely falling body   a)  u=0                       b)  v = 0           c)  t = 0                        d)  u = 0 and v = 0       [       ] 3.  Wave length of microwaves is         a)  10m to 10cm                       b)  0.7 mm to 100 mm c)  0.4 mm to 1 mm  d)  10 mm to 10 m                                                             [       ] 4.  In a stationary wave, the point at which the displacement is maximum is called. a)  Node                      b)  Antinode                 c)  Crest           d)  Trough                    [       ] 5.  a- particle is a ----change particle a)  Negative                  b)  Positive       c)  Neutral        d)  Positive and Negative          [       ] 6.  Which of the following shell has the least energy a)  L                 b)  M               c)  K                d)  N                                                    [       ] 7.  CaO is ---- in nature. a)  Neutral                    b)  Amphoteric c)  Basic           d)  Acids                      [       ] 8.  Solubility of a substance depends on ----- a)  Nature of solute                   b)  Nature of solvent     c)  Temperature            d)  All   [       ]   9.  The bond angle of diamond is --- a)  10o281                     b)  109o381                  c)  109o181                   d)  109o281 10.  Which of the following is a mixed fertilizer a)  KCl             b)  NH4Cl        c)  KnO           d)  Nitrophos K                                    [        ]   II Fill in the blanks with suitable words.   11.  When a body moves towards the earth due to gravity is taken as _________________. 12.  A group of wavelength of frequencies is called  _________________ 13.  Steradians is the unit of _________________ 14.  Aluminium is a _________________. 15.  RPM stands for _________________ 16.  Naphthalene is soluble is _________________ 17.  The extent of ionization of water increases with increasing _________________. 18.  _________________enzyme breaks the Glucose. 19.  Gray hard balls of cement is called _________________. 20.  The _________________ period is incomplete.   III  Match the following.   i)        Group – 'A'                                                                 Group – 'B'   21.   Atomic number                 (        )   A) Sum of the number of protons and neutrons     22.  Mass defect                        (        )     B)  4n + 2       23.   Mass number                    (        )     C)  4n + 3   24.  Neptunium series               (        )     D)  4n   25.  Uranium Series                  (        )     E)   Number of protons                                                                                                     F)   4n + 1                   G)  Stability of atom   ii)      Group – 'A'                                                             Group – 'B'   26.   Ethyl alcohol                   (        )     I)  C12H22 O11 27.   Sucrose                            (        )     J)  C12H35COOH 28.  Alkane                              (        )   K)  Cn H2n+2. 29.  Stearic acid                       (        )   L)  C8H18. 30.  Alkyne                              (        )   M)  CnH2n-2                                                               N)  C2H5OH                                                               O)   CnH2n

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previous prefinal x physical sciences

PHYSICAL SCIENCES (English Version) Parts A and B Time:  2 Hours                                                             Maximum Marks: 35   SECTION-I   Group-A                                                                                              5X2 = 10 Note:  1. Answer ANY FIVE questions choosing at least TWO from each of the following groups, i.e., Groups A & B.             2.  Each question carries 2 marks.   1.  Derive the relation between acceleration due to Gravity and Gravitational constant. 2.  Distinguish between step up and step down transformer. 3.  What are the uses of LASER in medicine. 4.  Explain a -decay and  b-decay.   Group 'B'   5.  What are the limitations of Arrhenius theory? 6.  Calculate the number of moles of NaOH present in 750 ml of 0.4 m of solution. 7.  Name two chromophores and auxochromes. 8.  Define ionization energy and explain the factors of ionization energy.   SECTION – II   Note: 1.  Answer any Four of the following Six questions.                  4X1 = 4 2.      Each question carries 1 mark.   9.  State Flemming's left hand rule. 10. What is damped vibration?. 11. Draw the symbol of p-n-p and n-p-n transistor. 12. Why are the alcohol distilleries located at the places of much water source? 13.  How are 'p' orbital designated. 14.  Define pH. SECTION – III   Note: 1.  Answer any Four questions, choosing Two from each of the following groups.            2.  Each question carries 4 marks.   Group 'A'                                                                                              4X4 = 16   15. Describe a method to determine the velocity of sound in air? 16. What are the differences between progressive waves theory and stationary waves? 17. Explain Nuclear Reactor with a labeled diagram.      18.  Two coils have an effective resistance 9 ohms when connected in series and 2 ohms when connected in parallel.  Find the values of individual Resistance of coils?   Group 'B'   19. State and explain with one example of Aufbau  principle? 20. Explain how does atomic Radius and ionization energy varies in a group and period? 21. How is soap industrially prepared?  22. What are Alkanes?  Write the substitution and combustion reaction of alkanes?   SECTION –IV                                                                                (Marks: 1 x 5=5)   Note:  1.  Answer Any One question from the following. 2.      Marks are 5.   23.  Draw and locate the neutral points when the north pole of a bar magnet faces geopgraphical north and when the south pole of bar magnet faces geopgraphical north.   24.  Draw a diagram showing the manufacture of Alcohol.

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Class: X SUB:
Mathematics
Topic :Real numbers
Time : 30 Min. Part- A
Marks: 5 X4 =20

1. If y = 33 + 1/33. Show that 3y3 -9y = 10

2. If lmn = 1 prove that 1/1 + l + m-1 + 1/1 + m + n -1 + 1/1 + n + l-1 =1.

3. If a 1/3 + b 1/3 + c 1/3 = 0 then show that (a + b + c) 3 = 27 abc.

4. If x = 0.1, find the value of [ 1 – { 1 – (1 –x 3) -1} -1 ] 1/3

5. If a + b + c = 0.

Part –B
Max Marks: 5 X2 =10

1. Show that Lt 6x - 5 = 3 .
x 0 2x + 5

2. Evaluate: Lt x +a - 2a
x a x – a

3. Solve the inequation 2x – 1  5.
5

4. If a = b3/y, b = c 4/x, c = a 5/z, then prove that xyz = 60.

5. Show that Lt x3 - 27 = 27.
x 3 x - 3

Topic : Analytical Geometry

Part- A
Marks: 5 X4 =20

1. A ( -1, 5), B (3, 1) and C (5, 7) are the vertices of triangle
ABC. D, E, F are the mid points of the sides BC, CA, and AB
respectively. Prove that the area of triangle ABC is 4 times the area
of the triangle DEF.

2. Find the equations of the line passing through the point (5, -3)
and whose sum of the intercepts on the coordinate axes is 5/6.

3. Find the area of triangle so formed by both the axes and a line
passing through the points ( 8, -3) and ( -4, 12).

4. Find the equation of the line which passes through the point (1,
-6) and whose product of the intercepts on the coordinate axes is one.

5. Find the equation of straight line passing through the point of
intersection of lines
3x + 2y = 5 and y – 4x + 3 = 0 and parallel to x + 2y – 4 = 0.

Part- B
Marks: 5 X4 =20

1. In what ratio is the segment joining the points (-3, 2) and (6, 1)
divided by y-axis.
2. In what ratio does P (4, 6) divide the joining of A (-2, 3) and B (6, 7).
3. If the area of the triangle formed with the vertices (t, 2t), (-2,
6), and (3, 1) is 5 sq. cms, then find 't.'
4. Show that the points (1, 2) (-3, 4) and (7, -1) are collinear.
5. Find a point on X-axis, equidistant from (3, 2) and (6, 4).

maths revision

Class: X                                                               SUB: Mathematics                                  Topic :Real numbers Time : 30 Min.                    Part- A                                  Marks: 5 X4 =20   1. If y = 3Ö3 + 1/3Ö3. Show that 3y3 -9y = 10   2. If lmn = 1 prove that 1/1 + l + m-1  + 1/1 + m + n -1 + 1/1 + n + l-1 =1.   3. If a 1/3 + b 1/3 + c 1/3 = 0 then show that (a + b + c) 3 = 27 abc.   4. If x = 0.1, find the value of [ 1 – { 1 – (1 –x 3) -1} -1 ] 1/3   5. If  a + b + c = 0.     Part –B                                                                                     Max Marks: 5 X2 =10   1. Show that   Lt            6x - 5  = 3  .                        x ®0       2x + 5                    2. Evaluate:  Lt            Öx +a - Ö2a                    x ®a              x – a   3. Solve the inequation ½2x – 1½ £ 5.                                             5   4. If a = b3/y, b = c 4/x, c = a 5/z, then prove that xyz = 60.   5. Show that  Lt            x3 - 27  = 27.                       x ®3       x - 3                                          Topic : Analytical Geometry   Part- A                                                                                        Marks: 5 X4 =20   1.  A ( -1, 5), B (3, 1) and C (5, 7) are the vertices of triangle ABC. D, E, F are the mid points of the sides BC, CA, and AB respectively. Prove that the area of triangle ABC is 4 times the area of the triangle DEF.   2. Find the equations of the line passing through the point (5, -3) and whose sum of the   intercepts on the coordinate axes is 5/6.   3. Find the area of triangle so formed by both the axes and a line passing through the points ( 8, -3) and ( -4, 12).   4. Find the equation of the line which passes through the point (1, -6) and whose product of the intercepts on the coordinate axes is one.   5. Find the equation of straight line passing through the point of intersection of lines 3x + 2y = 5 and y – 4x + 3 = 0 and parallel to  x + 2y – 4 = 0.   Part- B                                                                                        Marks: 5 X4 =20   1. In what ratio is the segment joining the points (-3, 2) and (6, 1) divided by y-axis. 2. In what ratio does P (4, 6) divide the joining of A (-2, 3) and B (6, 7). 3. If the area of the triangle formed with the vertices (t, 2t), (-2, 6), and (3, 1) is 5 sq. cms, then find 't.' 4. Show that the points (1, 2) (-3, 4) and (7, -1) are collinear. 5. Find a point on X-axis, equidistant from (3, 2) and (6, 4).

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DOUBLE SLIT EXPERIMENT

WATCH DOUBLE SLIT EXPT:www.freesciencelectures.com/video/dr-quantum-explains-double-slit-experiment/

ATOMIC STRUCTURE

Name: Assignment I Class: X Subject: Chemistry

ATOMIC STRUCTURE


I. Choose the correct answer
1. The total number of electrons present in an orbit is given by ( )
(a) n2 (b) 2n2 (c) (2l + 1) (d) –l….,0,….,+l
2. The total number of orbitals present in any orbit is given by ( )
(a) n2 (b) 2n2 (c) (2l + 1) (d) –l….,0,….,+l
3. The total number of orbitals present in any given sub-shell is given by ( )
(a) n2 (b) 2n2 (c) (2l + 1) (d) –l….,0,….,+l
4. The energy values of orbitals present in any sub level is given by ( )
(a) n2 (b) 2n2 (c) (2l + 1) (d) –l….,0,….,+l
5. Bohr’s theory is valid for ( )
(a) All atoms (b) All ions (c) Any atom or ion having one electron
(d) All molecules
6. Who introduced stationary orbits ( )
(a) Bohr (b) Schrodinger (c) Zeeman (d) Sommerfeld
7. Who introduced elliptical orbits ( )
(a) Bohr (b) Rutherford (c) Max Planck (d) Sommerfeld
8. Which of the following shell has the least energy ( )
(a) L (b) M (c) K (d) N
9. Which of the following has the energy value ‘3’ ( )
(a) L (b) M (c) K (d) N
10. Sommerfeld proposed elliptical orbits to explain ( )
(a) Fine structure (b) Zeeman effect (c) Stark effect
(d) Absorption of electromagnetic radiation.
11. Which of the following quantum numbers give size and energy of stationary orbits?
(a) n (b) l (c) m (d) s
12. Which of the following quantum number gives shape of orbitals? ( )
(a) n (b) l (c) m (d) s
13. The sub shells present in L-shell are ( )
(a) s only (b) s,p and d (c) s,p,d and f (d) s and p
14. f-orbitals are present in ( )
(a) K (b) N (c) M (d) L
15. The energy value of orbital can be found by the rule of ( )
(a) 2n2 (b) n2 (c) (2l + 1) (d) (n + l)
16. The maximum value of l for a given value of n is given by ( )
(a) (2l + 1) (b) (n – 1) (c) –l….,o,….+1 (d) n2





17. The maximum value of l for n = 5 is ( )
(a) 5 (b) 3 (c) –5 (d) 4
18. The orbitals corresponding to energy value of 3 are ( )
(a) 2p (b) 3p (c) 4s (d) 5p
19. The planetary model of an atom was proposed by ( )
(a) Sommerfeld (b) Bohr (c) Rutherford (d) Newton
20. Out of the following, which element is having anomalous electronic configuration
(a) C (b) Cu (c) Ca (d) Co ( )
21. Out of the following, which element is having the highest electron affinity ( )
(a) F (b) Cl (c) Br (d) I
22. Electrons occupy the orbitals of lowest energy. This is known as ( )
(a) Pauli’s exclusion principle (b) Hund’s rule of maximum multiplicity
(c) Rutherford planetary model (d) Aufbau principle
23. Pairing of electrons takes place when all the degenerate orbitals are occupied by one electron each. This rule is known as ( )
(a) Pauli’s exclusion principle (b) Hund’s rule of maximum multiplicity
(c) Rutherford planetary model (d) Aufbau principle
24. No two electrons will have all the four quantum numbers the same. This rule is known as ( )
(a) Pauli’s exclusion principle (b) Hund’s rule of maximum multiplicity
(c) Rutherford planetary model (d) Aufbau principle
25. Out of the following which orbitals are symmetric ( )
(a) s (b) p (c) d (d) f
26. The electronic configuration [Ne] 3s1 corresponds to ( )
(a) H (b) K (c) Ca (d) Na
27. Quantum theory of radiation was proposed by ( )
(a) Pauli (b) Bohr (c) Max Planck (d) Sommerfeld












Name: Assignment I Class: X Subject: Chemistry


ATOMIC STRUCTURE


II Fill in the blanks
1. The electrons were discovered by ____________________
2. Planetary model (or) nuclear model of atom was proposed by _______________
3. Quantum theory of radiation was proposed by ____________________
4. The concept of stationary orbits was proposed by ____________________
5. The concept of elliptical orbits was proposed by ____________________
6. Principle quantum number was proposed by ____________________
7. Azimunthal quantum number was proposed by ____________________
8. Magnetic quantum number was proposed by ____________________
9. Spin quantum number was proposed by ____________________
10. The shape of orbitals is given by the quantum number ____________________
11. s-orbitals are ____________________ in shape.
12. p-orbitals are ____________________ in shape.
13. The shape of d orbitals is _______________.
14. Relative energies of orbitals are given by ____________________
15. The representation of occupation of electrons in the orbitals is known as _______________
16. The electronic configuration is La is _______________
17. According to ________________ the electrons occupy the orbitals of lowest energy.
18. The orbitals having the same energy are known as _______________
19. The electronic configuration of Cr is ____________________
20. The electronic configuration of cu is ____________________
21. Ionisation energy is measured in ____________________
22. Electron affinity is measured in ____________________
23. The second ionization energy is always ___________ than the first ionization energy
24. Bohr proposed atomic theory based on ____________________
25. Angular momentum of revolving electron in a stationary orbit is _____________ h/2π
26. The location of an electron in an atom is given by ____________________
27. After filling the 3d orbitals, the electron enters into _______________ orbital.
28. After filling the 3p orbitals, the electron enters into _______________ orbital.
29. 3d10 4s1 is the valence electronic configuration of ________________
30. 3ds 4s1 is the valence electronic configuration of ____________________
31. The number of nodal regions present in any ‘ns’ orbital is given by the formula _______________





III 1 Mark questions
1. What are the fundamental (sub-atomic) particles present in the atom?
A. Electrons, protons and neutrons are the fundamental particles present in the atom.
2. What are nucleons?
A. Protons and neutrons are called as nucleons as they are present in the nucleus of an atom.
3. Who discovered electrons?
A. J.J. Thomson discovered electrons in 1903.
4. What is Max Planck’s quantum theory of radiation?
A. According to Max Planck’s quantum theory, the electromagnetic radiation is absorbed by matter not continuously but discontinuously in the form of packets of energy called ‘quanta’.
5. Write Planck’s equation?
A. E = h is the Plank’s equation, E is the energy absorbed or emitted
 is the frequency of radiation h is the Plank’s constant
6. What is the value of Planck’s constant?
A. The value of the Planck’s constant is 6.625 x 10-27 erg.sec
7. What is the basic for Bohr’s model of an atom?
A. Max Planck’s quantum theory of radiation is the basic for Bohr’s model of an atom.
8. What is a stationary orbit?
A. As the energy of the electrons revolving in certain specified paths remains stationary, they are called as stationary orbits.
9. What are different stationary orbits?
A. The different stationary orbits as proposed by Bohr are K, L, M, N, etc.,
10. What information does the prinicpal quantum number give?
A. Principal quantum number gives information about size and energy of orbits.
11. Who proposed the principal quantum number?
A. Niels Bohr proposed the principal quantum number.
12. Why the angular momentum of an electron is said to be quantized?
A. The electron revolving in the orbits, can accept only certain specified values like 1 h/2π, 2 h/2π, 3 h/2π, 4 h/2π … etc. Hence the angular momentum of the electron is said to be quantized.
13. What are degenerated orbitals?
A. The orbitals, present in a particular sub level, having the same energy are called as degenerate orbitals.
14. Who introduced elliptical orbits?
A. Sommerfeld introduced elliptical orbits.
15. Who introduced the Azimuthal quantum number?
A. Sommerfeld introduced the Azimuthal quantum number.
16. What are the limits of Azimuthal quantum number for a given value of ‘n’?
A. For a given ‘n’ the Azimuthal quantum number values are 0,1, … (n-1) i.e the highest value is (n –1)
17. Who introduced the magnetic quantum number?
A. Lande introduced the magnetic quantum number.
18. On what values, the values of ‘m’ depend?
A. The values of ‘m’ depend upon the value of l. The number of possible values (orientations) are (2l + 1) and the energy values are given by –l, -l + 1, ….0….(l-1), l etc.
19. How many m values are possible for l = 3?
A. If l = 3, then 2l + 1 = 7. Hence seven values are possible for l = 3.
20. What are the different values of m for l = 3?
A. For l = 3, the different values of m are –3, -2, -1, 0, 1, 2, 3.
21. What are the different values of m for l = 2?
A. For l = 2, the different values of m are –2, -1, 0, 1, 2.
22. What are the upper and lower limits of m for l = 4.
A. The upper limit is +4 and the lower limit is –4.
23. What are the upper and lower limits of m for l = 2.
A. The upper limit is +2 and the lower limit is –2
24. What happens to the orbitals of an atom in the presence of magnetic filed.
A. In the presence of magnetic field, the degenerate orbitals orient in different directions. The number of possible orientations are given by the formula (2l + 1)
25. Who introduced the spin quantum number?
A. Unlenbeck and Goudsmith introduced the spin quantum number in 1925
26. What are quantized values of spinning electron?
A. +1/2 and –1/2 are the only quantized values of spinning electron.
27. What is the necessary condition for the pairing of electrons in the same orbital?
A. The necessary condition for pairing of electrons in the same orbital is that they must possess opposite spins.
28. Define atomic orbital?
A. Atomic orbital is the region in space around the nucleus where there is a finite probability of finding the electron.
29. What is a nodal region?
A. The region around the nucleus, where the probability of finding the electron is zero, is called nodal region.
30. How many nodal regions are present in 4s orbital?
A. Since n =4, n-1 = 4-1 = 3, Hence three nodal regions are present in 4s orbital.
31. Write the designations of three P orbitals?
A. Px, Py, Pz are the designations of three P orbitals
32. Write the designations of all five d orbitals?
A. dxy, dyz, dzx, dx2 – y2, dz2 are the designations of all five d orbitals.
33. what is the electronic configuration?
A. Electronic configuration is the representation of the occupation of electrons in the orbitals.





IV 2 marks questions
1. Explain the presence of lines in the hydrogen spectrum?
2. Write the electronic configuration of Cr? Explain the anomaly?
3. Write the electronic configuration of Cu. Explain the anomaly?
4. State Aufbau principle?
5. What is Pauli’s exclusion principle?
6. State Hund’s rule?
7. Define atomic radius?
8. Write about atomic radius?
9. Define ionization energy? On what factors, it depends?
10. Define electron affinity?
11. Why the EA of F is less than that of CI?

VI 4 Marks questions
1. Write the important features of Rutherford’s planetary model?
2. What are the defects of Rutherford’s model?
3. State the postulates of Bohr’s model?
4. What are the defects of Bohr’s atomic model?
5. Discuss the features of modern atomic structure pertaining to the nucleus and stationary states.
6. State and explain with one example the Aufbau principle.
7. State and explain with one example the Hund’s rule of maximum multiplicity.
8. Define ionization energy and mention factors that influence it?

VII 5 Marks questions
1. Draw the shapes of ‘S’ and ‘P’ orbitals
2. Draw the shapes of five d orbitals
3. Draw the diagram showing the sequence of filling up of various atomic orbitals.
4. Draw the diagram showing Bohr’s model of atoms.
5. Draw the diagram showing the Sommerfeld’s elliptical orbits for n = 4.

KINEMATICS

Name: Assignment III Class: X Subject: Physics

KINEMATICS


I. Choose the correct answer.

1. The final velocity of a freely falling body ( )
(a) 0 (b) v = gt (c) v = 2gh (d) None of these
2. The initial velocity of a freely falling body is ( )
(a) 9.8 ms-1 (b)  (c) 9.8 ms-2 (d) 0
3. Maximum height reached by a body thrown up vertically with an initial velocity u is ( )
(a) u2.2 (b) u2 / 2g (c) 2g/u2 (d) u / g
4. The velocity of a body at its maximum height is ( )
(a) 10 ms-1 (b) 15 ms-1 (c) 0 (d) –10 ms-1
5. The time taken by a body to remain in the air which is moving under the influence of gravity is ( )
(a) 2u /g (b) u/g (c) 2h/g (d) 2h/g
6. The time taken by a body thrown up to reach the maximum height h is called its( )
(a) Time of descent (b) Time of flight (c) Time of ascent (d) None
7. The time taken by a freely falling body to reach the ground is called ( )
(a) Time of descent (b) Time of ascent (c) Time of flight (d) None of these
8. Time for which a body remains in the air is called ( )
(a) Time of flight (b) Time of descent (c) Time of ascent (d) Travelling time
9. For a body if the time of ascent is ‘t’ sec then the time of flight is ( )
(a) t sec (b) 2 t sec (c) 3 t sec (d) 4 t sec
10. The acceleration of a particle projected up at the highest point is ( )
(a) 0 (b) 9.8 cm s-2 (c) 980 cm s-1 (d) 9.8 ms-2

II. Fill in the blanks:

1. When a body moves towards the earth, acceleration due to gravity is taken as __________
2. When a body is projected upwards the acceleration due to gravity is taken as ___________
3. The formula top find the time of ascent is __________
4. Time of ascent is directly proportional to _______________
5. The maximum height reached by a body when it is projected upwards is directly proportional to __________
6. When a body os dropped from a height h, the velocity of the body on reaching the earth is _______________
7. For a body moving under the influence of gravity, time of ascent is equal to __________


8. The bodies projected vertically upwards are subjected to ____________________
9. Bodies falling without any force with a uniform acceleration under the influence of gravity are known as _______________
10. The upward velocity at any point in its flight is the __________ as its downward velocity at that point.

III. 1 Mark questions:

1. Write the equations of motion for a freely falling body
A. V = gt; h = 1/2gt2; v2 = 2gh
2. Write the equations of motion for a body thrown upwards.
A. v = u-gt; h = ut-1/2gt2; v2 = u2-2gh (or) v2 – u2 = -2gh
3. Define the terms a) Time of ascent b) Time of descent c) Time of flight.
A. Time of ascent: The time taken by a body to reach the maximum height when it is thrown up is called time of ascent.
Time of descent: The time taken by a freely falling body to reach the ground is called time of descent
Time of flight: The total time for which the body remains in air is called time of flight.

IV. 2 Marks questions:

1. Obtain a formula to find the maximum height reached by a body when it is projected vertically upwards with a velocity u
2. Derive a formula for the velocity on reaching the ground when a body is dropped from a height h.
3. A Stone is thrown vertically up with an initial velocity of 10 m/sec. Find the maximum height reached and the time of ascent. Take g = 10m/s2
4. A ball is thrown up and attains a maximum height of 80m. Find its initial

V. 4 Marks questions:

1. Show that time of ascent is equal to time of descent (or) Derive the formula to find the time of flight.

ELECTROMAGNETIC SPECTRUM

Name: Assignment - V Class: X Subject: Physics

ELECTROMAGNETIC SPECTRUM


I Choose the correct answer

1. Velocity of electromagnetic radiations is ( )
(a) 3 x1010ms-1 (b) 3 x 108ms-1 (c) 3 x 1010kms-1 (d) 3 x 108cms-1
2. The properties of different electromagnetic radiations are characterised by ( )
(a) Their Colour (b) Their Velocity (c) Their Frequency
(d) Their frequencies and wavelengths.
3. Which of the following has shortest wavelength ( )
(a) - Rays (b) Radio waves (c) Visible spectrum (d) Microwaves
4. Which of the following has shortest wavelength ( )
(a) Visible spectrum (b)  - rays (c) Radio waves (d) x – rays
5. Electromagnetic waves transport ( )
(a) Charge (b) Frequency (c) Wave length (d) Energy

II Fill in the Blanks

1. A _______________ is a group of wavelengths or frequencies.
2. ______________ glass absorbs infrared radiation.
3. Infra red radiations are nothing but a form of _____________
4. ______________ radiations are used to take photographs of objects in darkness.
5. ______________ rays are emitted in radioactivity

III 1 Mark questions

1. What is a spectrum?
A. A group of wavelengths or frequencies is called a spectrum.
2. What are electro magnetic radiations?
A. Electromagnetic radiations are characterised by oscillating electric and magnetic fields.
3. What are the various types of electromagnetic radiations?
A. The various types of electromagnetic radiations are
i) Visible spectrum ii) Infrared spectrum iii) Microwaves iv) Radio waves
v) Ultra Violet spectrum vi) x-rays and vii) - rays





IV 2 Marks questions

1. What are the common features among all the electromagnetic radiations?
2. Draw the diagram of electromagnetic wave

V 4 Marks questions

1. Discuss different types of electromagnetic radiations briefly?

ALKALINE EARTH METALS

Name: Assignment - IV Class: X Subject: Chemistry

ALKALINE EARTH METALS


I Choose the correct answer

1. [Ne] 3s2 is the electronic configuration of ( )
(a) Be (b) Mg (c) Ca (d) Sr
2. Valence electronic configuration of alkaline earth elements is ( )
(a) ns2 (b) ns2np6 (c) ns2np3 (d) ns1
3. Which of the following property increases from Be to Ra? ( )
(a) EN (b) IE (c) Atomic size (d) EA
4. Which of the following metal gives peroxide in addition to oxide? ( )
(a) Ba (b) Mg (c) Ca (d) Sr
5. Which of the following metal has highest EN? ( )
(a) Be (b) Mg (c) Ca (d) Ba
6. The MP of IIA group elements from top to bottom ( )
(a) Remains same (b) Increases (c) Decreases (d) Does not show any regular trend
7. The BP of IIA group elements from top to bottom ( )
(a) Remains same (b) Show regular trend (c) Decreases (d) Remains same
8. During electrolytic extraction of Mg, the cathode used is ( )
(a) Iron pot (b) Graphite (c) KCl and NaCl (d) Porcelein tube
9. During electrolytic extraction of Mg, the gas released at anode is ( )
(a) H2 (b) O2 (c) Cl2 (d) No gas is released

II Fill in the blanks

1. The chemical formula of magnesite is ___________________
2. The radioactive element of IIA group elements is _____________________
3. In IIA group elements, the atomic radius from top to bottom ____________________
4. In IIA group, the IE from top to bottom ___________________
5. In IIA group elements the electropositive character from top to bottom _____________
6. In IIA group elements the EN from top to bottom __________________
7. In IIA group elements the variation of MP and BP from top to bottom shows __________________ trend.
8. If IIA group elements are made to react with water (or) HCl (or) H2SO4 _______ gas is released




9. The general chemical formula for the hydrides of alkaline earth elements is _________
10. In the hydrides of IIA group elements, hydrogen carries _____________ charge.
11. Group IIA metals are extracted by the _______________ from their molten chlorides.
12. LiAlH4 acts as _______________ agent.
13. BeH2 is prepared from BeCl2 by using _____________________
14. All the alkaline earth chlorides are ionic except ___________________
15. ______________ gas is released at anode during the extraction of Mg by electrolysis.
16. The _______________ is used as cathode during the extraction of Mg by electrolysis.
17. __________________ and _______________ are added to reduce the MP and MgCl2 during electrolysis.
18. The % purity of Mg obtained by electrolysis is _______________
19. __________________ metal burns with dazzling white light when ignited.
20. Mg3N2 is dissolved in water, it releases ______________ gas.


III 1 Mark questions

1. Why does IE of group IIA elements decrease from Be to Ra?
2. Name three ores of magnesium.
3. Why KCl and Nacl are added to MgCl2 during Mg extraction?
4. Which metals are present in dolomite?
5. How many water molecules are present in Epsom salt?

IV 2 Marks questions

1. What are the electrodes used in the magnesium extraction?
2. Why the MP and BP show irregular trend from Be to Ra?
3. Why alkaline earth metals displace hydrogen form H2O?
4. Write about the method of preparation of BeH2?
5. Write reactions at electrodes during extraction of magnesium.

V 4 Marks questions

1. Write the reactions of group IIA elements with
(i) Oxygen (ii) Hydrogen (iii) Chlorine
2. Describe the method of extraction of Mg from its ore.

VI 5 Marks questions

1. Draw the chart showing the extraction of Mg from its ore

PERIODIC CLASSIFICATION OF ELEMENTS

Name: Assignment - III Class: X Subject: Chemistry

PERIODIC CLASSIFICATION OF ELEMENTS


I Choose the correct answer

1. In Dobereiner triad, the atomic weight of middle element is ( )
(a) The sum of atomic weights of first and third elements.
(b) The product of the atomic weight of first and third elements.
(c) The ratio of the atomic weights of first and third elements.
(d) The mean of the atomic weights of first and third elements.
2. The first classification of elements is attempted by ( )
(a) Bohr (b) Mosley (c) Mendeleef (d) Dobereiner.
3. The number of columns present in modern periodic table. ( )
(a) 15 (b) 16 (c) 17 (d) 18
4. Mendeleef’s periodic table is based on ( )
(a) Atomic volume (b) Atomic radius (c) Atomic weight (d) Atomic number
5. Mosley’s periodic table is based on ( )
(a) Atomic volume (b) Atomic radius (c) Atomic weight (d) Atomic number
6. The number of elements present in the first period are ( )
(a) 8 (b) 2 (c) 18 (d) 36
7. The incomplete period is ( )
(a) 7 (b) 6 (c) 1 (d) 2
8. The ionization potential in a group from top to bottom ( )
(a) Decreases (b) Increases (c) Remains same (d) Shows irregular trend
9. The atomic radius is measured in ( )
(a) eV (b) kJ/mole (c) kcal/mole (d) Angstrom

II Fill in the blanks

1. The earliest classification of elements is due to _____________________ in 1817.
2. Law of octaves was proposed by _____________________
3. Lother Meyer, proposed the periodic law based on the _______________ of elements.
4. Mendeleef arranged the elements in the increasing order of their _________________
5. The periodic table proposed by Mosley is known as _______________________
6. Mosley’s periodic law states that ‘the properties of the elements are the periodic function of their _____________________.





7. The chemical similarity of elements in a group is due to their similar _____________ electronic configuration.
8. Each period starts with ________________ and ends with ______________ elements.
9. Inert gases are the elements having _________________ electronic configuration.
10. Elements of s-block and p-block put together are known as ____________________
11. All types of elements, viz., metals, metalloids, non metals are placed in ________________
12. In a group the atomic radius ______________ from top to bottom.
13. In a group the EN __________________ from top to bottom.
14. EN of inert gases is __________________
15. The oxidizing power in a group _______________ and in a period _______________
16. The reducing power in a group _______________ and in a period________________

III 1 Mark questions

1. What is a triad?
A. A set of three elements arranged in the increasing order of their atomic weights is called a triad.
2. Give examples of three Dobereiner triads.
A. Cl, Br, I; S, Se, Te,; Li, Na, K; Fe, Co, Ni are the different triads arranged by Dobereiner.
3. What is Newland’s concept of octaves?
A. According to law of octaves, if the elements are arranged in the increasing order of their atomic weights, the properties of eight elements is a kind of repetition of the first one like the 8th note of an octave in music.
4. State Mendeleef’s periodic law.
A. Mendeleef’s periodic law states that ‘the properties of the elements are the periodic function of their atomic weights’.
5. Name the inert gases.
A. He, Ne, Ar, Kr, Xe, Rn are the inert gas elements.
6. Write the general electronic configuration of inert gases.
A. ns2, np6 is the general electronic configuration of inert gases.
7. What are inner transition elements?
A. Lanthanides and actinides (f-block elements) are called inner transition elements.
8. Define atomic radius.
A. The distance between the centre of the nucleus and the outermost oribital is defined as atomic radius (or) atomic size.






9. Define second ionization energy.
A. The minimum energy required to remove an electron from the outermost orbital of unipositive ion is defined as second ionization energy.
10. Define electronegativity
A. The tendency of a bonded atom in a molecule to attract the electron density of the shared pair of electrons is called as electronegativity
11. Define electropositive character
A. The tendency (or ability) of an atom to lose the valence electrons and become +vely charged ion is called electropositive character (or) metallic character.
12. Which group of the elements have highest electropositive character?
A. IA group elements have highest electropositive character.
13. Define oxidation and reduction.
A. Oxidation: Addition of oxygen to a given compound (or) removal of hydrogen from a given compound is called oxidation.
Reduction: Addition of hydrogen to a given compound (or) removal of oxygen from a given compound is defined as reduction.
14. Which group of elements can be used as oxidizing and reducing agents?
A. Oxidizing agents: VII A group-elements can be used as oxidizing agents.
Reducing agents: IA and IIA group elements can be used as reducing agents.

IV 4 Marks questions

1. How does the atomic radius vary in a period and in a group?
2. Explain the variation of ionization energy in a group?
3. Write about the salient features and draw backs of Mendeleef’s periodic table.
4. What re the features of long form of periodic table? (or) what are the salient features of Mosley’s periodic table?

CHEMICAL BOND

Name: Assignment - II Class: X Subject: Chemistry

CHEMICAL BOND


I Choose the correct answer

1. Octet configuration means ( )
(a) Having 6 valence electrons (b) Having 4 valence electrons
(c) Having 8 valence electrons (d) Having 2 valence electrons
2. At critical inter nuclear distance, the potential energy of the combining atoms is ( )
(a) Minimum (b) Maximum (c) It does not change
(d) Some times it is minimum and some times it is maximum.
3. Complete transfer of electrons from one atom to another leads to the formation of ( )
(a) Covalent bond (b) Polar covalent bond (c) Ionic Bond (d) None
4. Polar covalent bond is present in ( )
(a) Cl2 (b) H2 (c) F2 (d) HCl
5. Sharing of electrons lead to the formation of ( )
(a) Ionic bond (b) Covalent bond (c) Hydrogen bond (d) Metallic bond
6. If two pairs of electrons are shared between two atoms, that bond is called ( )
(a) Ionic bond (b) Co-ordinate covalent bond (c) Double bond
(d) Triple bond
7. If both the shared pair of electrons are contributed by only one atom it is called ( )
(a) Ionic bond (b) Covalent bond (c) Polar covalent bond (d) Co-ordinate covalent bond
8. Shape of H2O is ( )
(a) ‘V’ Shape (b) Pyramidal (c) Linear (d) Tetrahedral
9. Shape NH3 is ( )
(a) Linear (b) ‘V’ Shape (c) Tetrahedral (d) Pyramidal
10. Shape of PCl2 is ( )
(a) Linear (b) Trigonal bipyramidal (c) Tetrahedral (d) Pyramidal
11. Shape of BeCl2 is ( )
(a) Tetrahedral (b) Pyramidal (c) Linear (d) ‘V’ Shape
12. s-p overlap is present in ( )
(a) HCl (b) O2 (c) Cl2 (d) H2
13. p-p overlap is present in ( )
(a) HCl (b) Cl2 (c) BeCl2 (d) NH2
14. Triple bond is present in ( )
(a) Cl2 (b) H2 (c) CaCl2 (d) CaC2




15. The essential condition for the overlap of orbitals is that ( )
(a) They must be completely filled orbitals
(b) They must be only ‘s’ orbitals
(c) They must be half filled valence orbitals
(d) They must be only ‘p’ orbitals.

II Fill in the blanks

1. s-s overlap always leads to the formation of __________________ bond
2. End – on – end overlap of two orbitals always leads to the formation of ___________ bond
3. Side – on – side overlap of orbitals leads to the formation of _________________ bond
4.  - bond can exist ___________________
5.  - bond can’t exist ____________________
6. C2H2 has ___________________ bonds and __________________ bonds
7. N2 has _____________________ and _____________________ bonds
8. Oxygen has __________________ lone pairs of electrons in H2O molecule.
9. Nitrogen has __________________ lone pair of electrons in NH3 molecule.
10. ________________ atom is donor in (H3O)+
11. ________________ is acceptor in NH3.BF3

III 1 Mark questions

1. Name a molecule having s-s overlap.
A. Hydrogen
2. Name molecules having s-p overlap
A. HCl, H2O, NH3, HBr, HI, H2S
3. Name three molecules having p-p overlap
A. Cl2, O2, N2, Br2
4. Which orbitals can form ‘’ bond?
A. Side – on – side overlap of p-p orbitals can form  bond. [s orbitals are never involved in the formation of  bond]
5. Which orbitals can form  bond?
A. Overlap of s-s orbitals, end-on-end overlap of s-p, or p-p orbitals can form  bond.
6. Name the molecules that are linear in shape.
A. CO2, BeCl2 and HCN molecules have linear shape.
7. Name the molecules that have pyramidal shape.
A. Ammonia (NH3), Phosphorus trichloride (PCl3) and phosphine (PH3) have pyramidal shape.



8. Which molecules have triple bonds?
A. Acetylene (C2H2), Nitrogen (N2), Calcium Carbide (CaC2), Hydrogen Cyanide (HCN) have triple bonds.
9. Which molecules have double bonds in them?
A. Carbon dioxide (CO2), Oxygen (O2) and Ethylene (C2H4) have double bonds.
10. Which molecules have co-ordinate covalent bond?
A. Ammonia boron trifluoride (NH3BF3), Ammonium ion (NH4+), Hydronium ion (H3O+), Hexa hydrate iron (II) ion [Fe(H2O)6+2], Hexahydrate copper (II) ion [Cu(H2O)6]+2

IV 2 Marks questions

1. Explain how covalent bond is formed?
2. Explain the formation of HCl molecule by overlapping of orbitals?
3. Explain the formation of HCl molecule by electron dot formula?

V 4 Marks questions

1. Discuss the types of overlaps that are possible with s and p orbitals?
2. Explain the formation of a double bond.
3. Explain the formation of a triple bond.
4. Explain the formation of co-ordinate covalent bond.

VI 5 marks questions

1. Draw the neat diagrams how sigma and pi bonds are formed.
2. Draw the shapes of H2O, NH3 and PCl5