atomic structure

1.) Nernst glower is used to produce
A)	U-V-rays
B)	Microwaves
C)	Radio waves
D)	Far I.R rays
2.) Radius of 3rd bohr orbit is
A)	o‘>6.259Ao
B)	o‘>2.116Ao
C)	o‘>4.761Ao
D)	o‘>8.464Ao
3.) The nuclues of tritium consists of
A)	1 proton + 1 meutron
B)	1 proton + 3 neutrons
C)	1 proton + 0 neutons
D)	1 proton + 2 neutrons
4.) The elctronic state in which the hydrogen atom can absorb a photon but cannot emit a photon is
A)	2p
B)	3s
C)	1s
D)	4p
5.) Energy value which is equal to mass of one electron is—- ergs
A)	-7‘>8.2×10-7
B)	-8‘>9.2×10-8
C)	-10‘>8.2×10-10
D)	-8‘>4.1×10-8
6.) The source of ultraviolet radiations is
A)	Nernst glower
B)	oC’>Silicon carbide heated to 1500oC
C)	High pressure hydrogen discharge tube
D)	Tugsten filament bulb
7.) The charge of an electron is 1.6 x 10-19 coulombs. What will be the value of charge om Na+ ion
A)	-19 C’>1.6×10-19 C
B)	-19 C’>3.2×10-19 C
C)	-19 C’>2.4×10-19 C
D)	-19 C’>11×1.6×10-19 C
8.) The metal best used in photoelectric cells is
A)	Na
B)	Mg
C)	Al
D)	Cs
9.) Line spectrum is charecteristic of
A)	Atoms
B)	Molecules
C)	Any substance in solid state
D)	Any substance in liquid state`
10.) If the velocity of an electron in the second orbit of hydrogen atom is x, the velocity in fourth orbit will be
A)	x/16
B)	16x
C)	x/4
D)	x/2
11.) The value of rydberg constant is
A)	-1‘>109677 cm-1
B)	-1 s-1‘>109700 cm-1 s-1
C)	-1‘>10968 cm-1
D)	10970 m
12.) An oxide of nitrogen has a molecular weight of 30. Total number of electrons in one molecule of the compound is
A)	15
B)	30
C)	45
D)	60
13.) Which of the following is not a fundamental particle?
A)	Proton
B)	Neutron
C)	Alpha particle
D)	Electron
14.) The frequency associated with photon of radiation having a wavelength of 6000A0 is/
A)	14 Hz’>5×1014 Hz
B)	10 Hz’>5×1010 Hz
C)	14 Hz’>2×1014 Hz
D)	15 Hz’>5×1015 Hz
15.) Which of the following is not an electromagnetic radiation?
A)	Gamma rays
B)	Alpha rays
C)	Radio waves
D)	X-rays
16.) The isotopes of neutral atoms of an element differ in
A)	Atomic numbers
B)	Mass number
C)	Number of electrons
D)	Chemical properties
17.) The value of e/m for an electron is?
A)	8 c/g’>1.78 X 108 c/g
B)	-24 c/g’>1.6724 X 10-24 c/g
C)	0.005486 c/g
D)	1.00866 c/g
18.) The number of neutrons present in the radioactive isotope of hydrogen is?
A)	0
B)	1
C)	2
D)	3
19.) The first use of quantum theory to explain the structure of atom was made by
A)	Planck
B)	Einstein
C)	Bohr
D)	Heiseberg
20.) The spectrum obtained from incandescent solids is
A)	Continuous
B)	Line
C)	Band
D)	None of these
21.) The radiation with highest wave number
A)	Microwaves
B)	X-rays
C)	I.R_rays
D)	Radiowaves
22.) The radius of the first orbit of hydrogen is 0.53Ao. The radius of second orbit of He+ would be
A)	o‘>0.265Ao
B)
C)	o‘>2.12Ao
D)	o‘>0.53Ao
23.) The modern atomic mass unit is based on the mass of
A)	12‘>C12
B)	14‘>C14
C)	1‘>H1
D)	14‘>N14
24.) The mass of one mole of electron is
A)	1.008g
B)	0.55mg
C)	0.184mg
D)	1.673 mg
25.) The ratio of the radii of the first three orbits in an atom of hydrogen is
A)	1:4:9
B)	9:4:1
C)	1:2:3
D)	3:2:1

periodic classification

1.) The period in which only single block elements are present by definition
A)	6
B)	2
C)	3
D)	1
2.) The 4f-subshell is successively filled for
A)	Rare earths
B)	Rare gases
C)	Transition metals
D)	Alkaline earth metals
3.) Which of the following has the largest atomic radius
A)	AI
B)	oC’>Silicon carbide heated to 1500oC
C)	CI
D)	Na
4.) The atomic number of the element which is not included in the main body of the period table
A)	43
B)	57
C)	68
D)	80
5.) Largest atom among the following is
A)	F
B)	Br
C)	I
D)	I
6.) The general electronic configuration of elements of carbon family
A)	2 np4‘>ns2 np4
B)	2 np3‘>ns2 np3
C)	2 np1‘>ns2 np1
D)	2 np2‘>ns2 np2
7.) Which of the following has both members from the same group of the periodic table
A)	Mg, Cs
B)	Mg, Sr
C)	Mg, Ci
D)	Na, Ci
8.) Inert gas element which has a different valence shell configuaration
A)	Xe
B)	Ne
C)	Kr
D)	He
9.) The period in which s-block, p-block and d-block elements are presents
A)	1
B)	6
C)	7
D)	3
10.) Atoms of the following group possess the highest ionisation energies
A)	IA
B)	IIA
C)	VA
D)	Zero
11.) Which of the following is not a periodic property
A)	Valency
B)	Specific heat
C)	Lonisation portential
D)	Atomic size
12.) Set of continuous atomic numbers of the elements present in the same group as well as same period
A)	3, 11, 19
B)	60, 61, 62
C)	30, 31, 32
D)	88, 89, 90
13.) In the periodic table, the elements are arranged in the periods following the
A)	Hand’s rule of maximum multiplicity
B)	Pauli’s exclusion principle
C)	Aufbau principle
D)	Both (1) and (2)
14.) Metal used as catalyst in the hydrogenation of vegetable oils
A)	Iron
B)	Molybdenum
C)	Nickel
D)	Sodium
15.) The most electropositiveelement is
A)	I
B)	Mg
C)	Cs
D)	Li
16.) Atomic numbers of actinides
A)	57 to 71
B)	80 to 103
C)	58 to 71
D)	90 to 103
17.) Mendeleef’s periodic law is based on
A)	Atomic weight
B)	Atomic number
C)	Number of neutrons
D)	Specific heat
18.) Eka silicon is now known as
A)	Scandium
B)	Gallium
C)	Germanium
D)	Boron
19.) Which of the following is an alloy of non- transition elements
A)	Elektron
B)	Brass
C)	Bronze
D)	German silver
20.) The number of elements present in 2nd, 3rd, 4th, and 5th periods of modern periodic table respectively are
A)	2,8,8&18
B)	8,8,18&32
C)	8,8,18&18
D)	8,18,18&32
21.) Which of the following is an element present in the d-block, but not a transition element
A)	Cd
B)	Cu
C)	Ca
D)	None of these
22.) The following ion is colourless in aqueous solution
A)	2+‘>Ca2+
B)	3+‘>Sc3+
C)	2+‘>Zn2+
D)	All the above
23.) Atoms of the following group possess the lowest ionisation energies
A)	IA
B)	IIA
C)	VA
D)	Zero
24.) In the periodic table transition elements begin with
A)	Scandium
B)	Zinc
C)	Copper
D)	Mercury
25.) The longest and shortest periods are
A)	1 & 6
B)	2 & 6
C)	6 & 1
D)	1 & 7

physics [simple facts in physics]

1. Mechanics
2. 1. Weight (force of gravity) decreases as you move away from the earth by distance squared.
   2. Mass and inertia are the same thing.
   3. Constant velocity and zero velocity means the net force is zero and acceleration is zero.
   4. Weight (in newtons) is mass x acceleration (w = mg). Mass is not weight!
   5. Velocity, displacement [s], momentum, force and acceleration are vectors.
   6. Speed, distance [d], time, and energy (joules) are scalar quantities.
   7. The slope of the velocity-time graph is acceleration.
   8. At zero (0) degrees two vectors have a resultant equal to their sum. At 180 degrees two vectors have a resultant equal to their difference. From the difference to the sum is the total range of possible resultants.
   9. Centripetal force and centripetal acceleration vectors are toward the center of the circle- while the velocity vector is tangent to the circle.
   10. An unbalanced force (object not in equilibrium) must produce acceleration.
   11. The slope of the distance-tine graph is velocity.
   12. The equilibrant force is equal in magnitude but opposite in direction to the resultant vector.
   13. Momentum is conserved in all collision systems.
   14. Magnitude is a term use to state how large a vector quantity is.
3. 1. Energy
4. 1. 
      
   2. Mechanical energy is the sum of the potential and kinetic energy.
   3. Units: a = [m/sec²], F = [kg?m/sec²] (newton), work = pe= ke = [kg?m²/sec²] (joule)
   4. An ev is an energy unit equal to 1.6 x 10^-19 joules
   5. Gravitational potential energy increases as height increases.
   6. Kinetic energy changes only if velocity changes.
   7. Mechanical energy (pe + ke) does not change for a free falling mass or a swinging pendulum. (when ignoring air friction)
   8. The units for power are [joules/sec] or the rate of change of energy.
5. 1. Electricity
6. 1. 
      
   2. A coulomb is charge, an amp is current [coulomb/sec] and a volt is potential difference [joule/coulomb].
   3. Short fat cold wires make the best conductors.
   4. Electrons and protons have equal amounts of charge (1.6 x 10^-19 coulombs each).
   5. Adding a resistor in parallel decreases the total resistance of a circuit.
   6. Adding a resistor in series increases the total resistance of a circuit.
   7. All resistors in series have equal current (I).
   8. All resistors in parallel have equal voltage (V).
   9. If two charged spheres touch each other add the charges and divide by two to find the final charge on each sphere.
   10. Insulators contain no free electrons.
   11. Ionized gases conduct electric current using positive ions, negative ions and electrons.
   12. Electric fields all point in the direction of the force on a positive test charge.
   13. Electric fields between two parallel plates are uniform in strength except at the edges.
   14. Millikan determined the charge on a single electron using his famous oil-drop experiment.
   15. All charge changes result from the movement of electrons not protons (an object becomes positive by losing electrons)
7. 1. Magnetism
8. 1. 
      
   2. The direction of a magnetic field is defined by the direction a compass needle points.
   3. Magnetic fields point from the north to the south outside the magnet and south to north inside the magnet.
   4. Magnetic flux is measured in webers.
   5. Left hands are for negative charges and right hands are for positive charges.
   6. The first hand rule deals with the B-field around a current bearing wire, the third hand rule looks at the force on charges moving in a B-field, and the second hand rule is redundant.
   7. Solenoids are stronger with more current or more wire turns or adding a soft iron core.
9. 1. Wave Phenomena
10. 1. 
       
    2. Sound waves are longitudinal and mechanical.
    3. Light slows down, bends toward the normal and has a shorter wavelength when it enters a higher (n) value medium.
    4. All angles in wave theory problems are measured to the normal.
    5. Blue light has more energy. A shorter wavelength and a higher frequency than red light (remember- ROYGBIV).
    6. The electromagnetic spectrum (radio, infrared, visible. Ultraviolet x-ray and gamma) are listed lowest energy to highest.
    7. A prism produces a rainbow from white light by dispersion (red bends the least because it slows the least).
    8. Light wave are transverse (they can be polarized).
    9. The speed of all types of electromagnetic waves is 3.0 x 10⁸ m/sec in a vacuum.
    10. The amplitude of a sound wave determines its energy.
    11. Constructive interference occurs when two waves are zero (0) degrees out of phase or a whole number of wavelengths (360 degrees.) out of phase.
    12. At the critical angle a wave will be refracted to 90 degrees.
    13. According to the Doppler effect a wave source moving toward you will generate waves with a shorter wavelength and higher frequency.
    14. Double slit diffraction works because of diffraction and interference.
    15. Single slit diffraction produces a much wider central maximum than double slit.
    16. Diffuse reflection occurs from dull surfaces while regular reflection occurs from mirror type surfaces.
    17. As the frequency of a wave increases its energy increases and its wavelength decreases.
    18. Transverse wave particles vibrate back and forth perpendicular to the wave direction.
    19. Wave behavior is proven by diffraction, interference and the polarization of light.
    20. Shorter waves with higher frequencies have shorter periods.
    21. Radiowaves are electromagnetic and travel at the speed of light (c).
    22. Monochromatic light has one frequency.
    23. Coherent light waves are all in phase.
11. 1. Geometric Optics
12. 1. 
       
    2. Real images are always inverted.
    3. Virtual images are always upright.
    4. Diverging lens (concave) produce only small virtual images.
    5. Light rays bend away from the normal as they gain speed and a longer wavelength by entering a slower (n) medium {frequency remains constant}.
    6. The focal length of a converging lens (convex) is shorter with a higher (n) value lens or if blue light replaces red.
13. 1. Modern Physics
14. 1. 
       
    2. The particle behavior of light is proven by the photoelectric effect.
    3. A photon is a particle of light {wave packet}.
    4. Large objects have very short wavelengths when moving and thus can not be observed behaving as a wave. (DeBroglie Waves)
    5. All electromagnetic waves originate from accelerating charged particles.
    6. The frequency of a light wave determines its energy (E = hf).
    7. The lowest energy state of a atom is called the ground state.
    8. Increasing light frequency increases the kinetic energy of the emitted photo-electrons.
    9. As the threshold frequency increase for a photo-cell (photo emissive material) the work function also increases.
    10. Increasing light intensity increases the number of emitted photo-electrons but not their KE.
15. 1. Internal Energy
16. 1. 
       
    2. Internal energy is the sum of temperature (ke) and phase (pe) conditions.
    3. Steam and liquid water molecules at 100 degrees have equal kinetic energies.
    4. Degrees Kelvin (absolute temp.) Is equal to zero (0) degrees Celsius.
    5. Temperature measures the average kinetic energy of the molecules.
    6. Phase changes are due to potential energy changes.
    7. Internal energy always flows from an object at higher temperature to one of lower temperature.
17. 1. Nuclear Physics
18. 1. 
       
    2. Alpha particles are the same as helium nuclei and have the symbol .
    3. The atomic number is equal to the number of protons (2 for alpha)
    4. Deuterium () is an isotope of hydrogen ()
    5. The number of nucleons is equal to protons + neutrons (4 for alpha)
    6. Only charged particles can be accelerated in a particle accelerator such as a cyclotron or Van Der Graaf generator.
    7. Natural radiation is alpha (), beta () and gamma (high energy x-rays)
    8. A loss of a beta particle results in an increase in atomic number.
    9. All nuclei weigh less than their parts. This mass defect is converted into binding energy. (E=mc²)
    10. Isotopes have different neutron numbers and atomic masses but the same number of protons (atomic numbers).
    11. Geiger counters, photographic plates, cloud and bubble chambers are all used to detect or observe radiation.
    12. Rutherford discovered the positive nucleus using his famous gold-foil experiment.
    13. Fusion requires that hydrogen be combined to make helium.
    14. Fission requires that a neutron causes uranium to be split into middle size atoms and produce extra neutrons.
    15. Radioactive half-lives can not be changed by heat or pressure.
    16. One AMU of mass is equal to 931 meV of energy (E = mc²).
    17. Nuclear forces are strong and short ranged.
19. 1. General
20. 1. 
       
    2. The most important formulas in the physics regents are:
       
    3. Physics is fun. (Honest!)