PODCAST
Physical Science 10th Special
1. Heat
1. Which of the following is a warming process ____.
a) Evaporation b) Condensation
c) Boiling d) All the above
2. The temperature of a steel rod is 330K. Its temperature ºC is ____.
a) 45ºc b) 57ºc
c) 59ºC d) 63ºc
3. Specific heat S = ____.
a) b) QDt c) d)
4. ____ is a cooling process.
a) Boiling b) Evaporation
c) Condensation d) All the above
5. ____ is used as a coolant.
a) Benzene b) Kerosene
c) Grease d) Water
6. 1 Calorie = ____ joule
a) 4.186 b) 0.45
c) 41.86 d) 0.0418
7. Which one has highest specific heat?
a) Benzene b) Lead
c) Water d) Kerosene
8. Which of the following is surface phenomenon?
a) Evaporation b) Condensation
c) Freezing d) Melting
9. Rate of evaporation depends on
a) Surface Area
b) Humidity c) Temperature
d) All the above
10. The phase changes from gas to liquid is called
a) Boiling b) Evaporation
c) Condensation d) Humidity
Answers
1) b; 2) b; 3) c; 4) b; 5) d;
6) a; 7) c; 8) a; 9) d; 10) c.
Important Questions
1 Mark
1. Convert 30ºC into Kelven Scale?
A. K = C+273; T = 30+273=303k
2. What is latent heat of vapourization?
A. The heat energy required to change 1 gm of liquid to gas at constant temperature is called latent heat of vapourization.
3. Why do we sweat while doing a work?
A. When we work our bodies produce heat. As a result the temperature of the skin becomes higher and water in the sweat glands start evaporating. This evaporation cools the body.
4. What is humidity?
A. The amount of water vapour present in air is called humidity.
5. What are the factors affecting rate of evaporation?
A. Surface area, temperature and amount of water vapour already present in the surrounding air.
6. A desert is very hot in the day and very cool at night why?
A. Because low specific heat capacity air above earth heated up quickly in the day and cooled quickly at night.
7. Why does ice floats on water?
A. When water converts into ice its volume increases so density decreases. Hence density of ice is less than water so ice floats on water.
8. What is the effect of pressure on melting point of ice?
A. With increase in pressure the melting point of ice reduces.
9. What is the major difference between boiling and evaporation?
A. Evaporation is the surface phenomenon while boiling is a bulk phenomenon.
10. What is the value of latent heat of fusion of ice?
A. 80 cal/gm
2 Marks
1. Explain why dogs pant during hot summerdays using the concept of evaporation?
2. Why do we get dew on the surface of a cold soft drink bottle kept in open air?
3. Write the differences between evaporation and boiling?
4. What happens to the water when wet clothes dry?
5. What happens, when water is kept in a refrigerator?
4 Marks
1. Your teacher made an experiment that shows the information of dew and frost. Explain how you show they effect on the rate of evaporation?
2. Define evaporation. Explain what are the affecting factors of evaporation and how they effect on the rate of evaporation?
3. Determine the specific heat of solid experimentally?
4. How do you appreciate the role of the higher specific heat of water in stabilizing atmospheric temperature during winter and summer seasons?
2. Chemical Reactions and Equations
1. Fe2O3+2Al ®Al2O3+Fe
The above reaction is an example of
a) Combination reaction
b) Decomposition Reaction
c) Displacement reaction
d) Double decomposition reaction
2. The chemical equation
BaCl2+Na2SO4®BaSO4+2NaCl
represents following type of chemical reaction
a) Displacement b) Combination
c) Decomposition
d) Double decomposition
3. To decompose a compound as need.
a) Heat b) Sunlight
c) Electricity d) Anyone
4. In the equation CuO+H2®Cu+H2O reducing agent is
a) CuO b) H2
c) Cu d) H2O
5. Corrosion is an ____ reaction
a) oxidation b) Reduction
c) Redox d) None
6. Rancidity is an ____ Reaction
a) Reduction b) oxidation
c) Redox d) All
7. Rancidity is prevented by
a) Antioxidants
b) Painting
c) Keeping food in air tight container
d) a & c
8. Precipitate in a reaction is indicated by which arrow mark
a) b) ®
c) ¯ d) ¬
9. CuO+H2®Cu+H2O is ____ reaction.
a) Oxidation b) Combustion
c) Redox d) Substitution
10. Formula of slaked lime
a) CaO b) CaCO3
c) Ca(OH) 2 d) CaSO4
Answers
1) c; 2) d; 3) d; 4) b; 5) a; 6) b; 7) d; 8) c; 9) c; 10) c.
Important Questions
1 Mark
1. State important uses of decomposition reaction?
A. Extract metals from their compounds & digestion of food.
2. What happens when silver chloride exposed to sunlight?
A. 2 AgCl ®2Ag+Cl2
3. Why photosynthesis reaction considered as endothermic reaction?
A. During photosynthesis plants absorb heat from sunlight so photosynthesis reaction is example for endothermic reaction.
4. What is antioxidant?
A. The substance which is used to prevent oxidation are called antioxidants.
5. Why do we apply paint on iron articles?
A. To prevent corrosion.
6. Give any two examples of double displacement reactions?
A. (i) BaCl2+Na2SO4®2NaCl+BaSO4
(ii) 2KI+Pb(NO3)2® PbI2+2KNO3
7. Which metal is used in the manufacture of Diwali crackers?
A. Magnesium.
8. Which gas is used in the chips like Lays and Kurkure’s?
A. Nitrogen gas
9. Write the formula of rust?
A. Fe2O3.XH2O
10. Which type of reaction involved when silver bromide is exposed to sunlight?
A. Photo chemical reaction.
2 Marks
1. What do you mean by corrosion? How can you prevent it?
2. Why does respiration reaction considered as exothermic reaction? Explain?
3. A shiny brown coloured ‘X’ on heating in air becomes black colour. Can u predict the element ‘X’ and the black colour substance formed? How do you support your predictions?
4. What is meant by precipitation reaction? Give example?
4 Marks
1.Take two beakers and prepare lead nitrate aqueous solution and Potassium iodide aqueous solutions. What are the colours of solutions. Now mix them in another beaker. What happens? What type of chemical reaction it is? What are products obtained?
2.Latha take some quantity of powder of a substance in a test tube. Heated it with spirit lamp. A gas was liberated. She send the gas into another test tube. The colour of solution in the second test tube turned into milk white?
1) Which substance was heated
2) Which gas is liberated
3) What was the solution taken in second test tube
4) Which type of chemical reactions involved the experiment
3. Balance the following chemical equations including the physical states?
a) C6H12O6 ®C2H5OH + CO2
b) Fe+O2 ®Fe2O3
c) NH3+Cl2®N2H4+NH4Cl
d) Na+H2O®NaOH+H2
3. Reflection of Light by different surfaces
1. Magnification m = ____
a) v/u b) u/v
c) h0/h1 d) h1/h0
2. The distance between pole and centre of curvature is
a) radius of curvature b) pole
c) focal length d) none
3. The equation of mirror formula is
a) b)
c) d)
4. Radius of curvature = …… x focal length.
a) 3 b) 2 c) 4 d) ½
5. The mirror used by ENT specialist is
a) plane mirror b) convex mirror
c) concave mirror d) None
6. For a concave mirror, the focal length is
a) Positive b) negative
c) zero d) None
Answers
1) d; 2) a; 3) b; 4) b; 5) c;
6) b.
Important Questions
1 Mark
1. State Fermat’s principle?
A. It states that the light selects the path which takes the least time to travel. It is also applicable to reflection of light.
2. Which objects at your home act as spherical mirrors?
A. Cooking vessels, sink, spoons.
3. Which type of mirrors are used in head light of vehicles?
A. Concave mirrors are used in the head lights of vehicles.
4. Why does our image appear thin or bulged?
A. Due to converging (or) diverging of light rays from the mirror.
5. Write the mirror formula?
A. ƒ: focal length, u : object
distance, v = image distance
6. Which mirrors are used in saloons and sweets shops?
A. Plane mirrors
7. Which principle involved in the working of periscope?
A. Principle of reflection of light.
8. Which mirrors are used by dentists and ENT specialist?
A. Concave mirrors
9. Preetham saw his face in the cars mirror and found that his image is small. Which type of mirror is that?
A. Convex mirror.
10. Which principle is used in the law of reflection?
A. Fermat principle.
2 Marks
1. How do you find the focal length of a concave mirror?
2. Write the rules for sign convention of spherical mirrors?
3. Explain the process of making a solar cooker/heater (or) Make a solar heater/ cooker and explain the process of making.
4. How do you appreciate the role of spherical mirrors in daily life? (or) What are the applications of spherical mirrors in daily life?
5. Write any two uses of convex and concave mirrors in our daily life?
6. Why does an image suffer lateral inversion?
4 Marks
1. How do you support your answer to “When light gets reflected from a surface, it selects the path that takes the least time”?
2. What is magnification? Derive the formula for magnification of spherical mirrors?
3. Write the experimental method in verification laws of reflection in plane mirrors?
4. Write the experimental method to measures the distances of object and image using concave mirror? And write the table for observations?
4. Acids, Bases and Salts
1. The colour of methyl orange indicator in acidic medium is
a) Yellow b) Orange
c) Red d) Green
2. The colour of phenolphthalein indicator in basic solution is
a) Pink b) Yellow
c) Blue d) Red
3. Colour of Methyl orange in alkali conditions
a) Orange b) Yellow
c) Blue d) Red
4. Which one of the following types of medicines is used for treating indigestion
a) Antibiotic b) Antacid
c) Antiseptic d) Analgesic
5. Water soluble bases are known as
a) Neutral b) base
c) acid d) alkali
6. Acid substances contains ……ions.
a) OH- b) H+
c) Na+ d) Cl-
7. The acid form in stomach is
a) HCl b) H2SO4
c) HNO3 d) CH3COOH
8. PH was introduced by
a) Sorensen b) Lewis
c) Pauling d) Perkin
9. Formula of plastic of Paris
a) CaSO42H2O b) CaSO4½H2O
c) CaSO4 d) Ca(NO3) 2
10. ____ gas is evolved when metal carbonates react with acids
a) H2 b) O2 c) CO2 d) NO2
Answers
1) c; 2) a; 3) b; 4) b; 5) d;
6) b; 7) a; 8) a; 9) b; 10) c.
Important Questions
1 Mark
1. Why does distilled water not conduct electricity.
A. Distilled water does not conduct electricity due to no ions present in distilled water.
2. Give two examples of neutralization reaction.
A. NaOH+HCl ®NaCl+H2O
NaOH+CH3COOH ®CH3COONa+H2O
3. What is acid rain?
A. When pH of rain water is less than 5.6, it is called acid rain.
4. Plaster of Paris should be stored in a moisture proof container. Explain.
A. The Plastic of Paris should be stored in the moisture proof container as it absorbs wa-ter from moisture and turns in to Gypsum.
5. What are Amphoteric oxides.
A. Oxides capable of showing properties for both acids & bases.
6. Which substance is used for making chalks and fire proof material.
A. Plaster of Paris.
7. Give any two examples of olfactory indicatiors.
A. Vanilla essence & clove oil.
8. Write the formula of baking soda & washing soda.
A. Baking soda : NaHCO3
Washing Soda : Na2CO3.10H2O
9. Which acid derived from lemon and turn blue litmus in Red.
A. Citric acid.
10. Define universal pH indicator.
A. A mixture of several indicator is called universal pH indicator.
11. Define alkalis.
A. Bases which are soluble in water are called alkalis.
12. Which substance used to control the stomach pain causes due to indigestion.
A. Antacid.
2 Marks
1. What happens when an acid or base is mixed with water?
2. Why does distilled water not conduct electricity where rain water does?
3. Plaster of paris should be stored in a moisture proof container explain why?
4. Fresh milk has a pH of 6. How does the pH change as it turns to curd? Explain your answer?
5. What is baking powder? How does it make the cake soft and spongy?
4 Marks
1. Write the formulae for the following salts. (a) Sodium sulphate (b) Ammonium chloride. Identify the acids and bases for which the above salts are obtained also write chemical equations for the reactions between such acids and bases which type of chemical reactions they are?
2. Compounds such as alcohols and glucose contain hydrogen but are not categorized as acids. Describe an activity to prove it.
3. Acids produce ions only in aqueous solution? Justify your answer with an activity.
4. Write any 4 uses of (a) Washing soda
(b) Baking soda.
5. refraction of light
at plane surfaces
1. Speed of light of a medium depends upon ____ of the medium
a) Medium b) Optical Density
c) Material d) volume
2. Speed of light in vacuum is nearly equal to
a) 2´108 m/sec b) 0.3´108 m/sec
c) 3´108 m/sec d) 4´108 m/sec
3. The critical angle of diamond is
a) 24.8º b) 24.4º
c) 23.4º d) 22.4º
4. The angle of refraction for critical angle is
a) 60º b) 90º
c) 80º d) 45º
5. In a glass slab, refraction takes place ____ times
a) 5 b) 2 c) 3 d) 4
6. The brilliance of diamond is due to
a) refraction b) reflection
c) interference
d) total internal reflection
7. Refractive index of a medium depends on
a) Nature of material
b) Wavelength of light used
c) a and b d) None
8. When light ray travels from denser to rarer medium, the relation between r and i is ____
a) r = i b) r > i
c) r < i d) r ³ i
9. A lemon kept in a glass of water appears to be
a) Bigger b) Smaller
c) Same size
d) Some times bigger some times smaller
10. is called
a) Snell’s law b) Boyle’s law
c) Pascal’s law d) Grahem’s law
Answers
1) b; 2) c; 3) b; 4) b; 5) b;
6) d; 7) c; 8) b; 9) a; 10) a.
Important Questions
1 Mark
1. What is optically denser medium?
A. The medium in which speed of light is less is called optically denser medium.
2. Determine the refractive index of benzene if the critical angle of it is 42º?
A. Critical angle of benzene (C) = 42º
3. What is lateral shift?
A. Side wise shift when a ray of light is incident obliquely on a parallel sided glass slab.
4. Name the colour of light for which critical angle is minimum?
A. Violet.
5. What are applications of total internal reflection?
A. Formation of mirages, brilliance of diamond, working of optical fibre.
6. Find the critical angle for a material of refractive index Ö2?
A.
7. When is angle of incidence is equal to the angle of refraction?
A. When light travels perpendicular to surface it will not undergo any refraction. So angle of incidence is equal to angle of refraction.
8. What is the principle involved in the optical fibre?
A. Total internal reflection.
9. Define shift?
A. The perpendicular distance between the emergent and incident rays which are parallel is called shift.
10. Is the refractive index for a given pair of medium depend on the angle of incidence?
A. No. It is independent of the angle of incidence.
2 Marks
1. Why is it difficult to shoot a fish swimming in water?
2. Take a bright metal ball and make it black with soot in a candle flame. Immerse it in water. How does it appear and why?
3. How do you appreciate the role of Fermat principle in drawing ray diagrams.
4. What is the angle of deviation produced by a glass slab? Explain with ray diagram?
4 Marks
1. Derive the Snell’s formula from Fermat principle? (or) Derive the formula in relation with angle of incidence and angle of refraction?
2. What is meant by Total internal reflection and derive the relation between critical angle and total internal reflection?
3. Explain the experiment that showing the relation between angle of incidence and angle of refraction through the figure?
4. Explain the experiment that showing the determination of position and nature of image formed by a glass slab through the figure?
6. Refraction of light at curved surfaces
1. S.I unit of the power of a lens is
a) cm b) metre
c) Dioptre d) Decibel
2. The power of a concave lens is
a) Positive b) Negative
c) a (or) b d) None
3. When a refracted ray is distracted from its original path this displacement is called
a) reflection b) refraction
c) dispersion d) lateral
4. The power of a convex lens is
a) Positive b) Negative
c) Neutral d) None
5. Which of the following lens act as converging lens.
a) biconvex b) Plano convex
c) concave convex d) All
Answers
1) c; 2) b; 3) d; 4) a; 5) d.
Important Questions
1 Mark
1. Define focal point?
A. The rays coming from the sun parallel to the principal axis of concave mirror converge to a point. This point is called Focus or focal point.
2. Give two uses of a convex lens?
A. (i) used in projectors
(ii) Cameras
3. Do only convex lens converge?
A. No, a concave mirror also converge.
4. What is positive lens?
A. Convex lens.
5. Define principal axis?
A. The line joining the centre of curvature and the pole is called principal axis.
6. Write the lens formula?
7. Write the lens makers formula?
A.
8. Which lens will form both real and virtual images?
A. Plane mirror.
9. What is negative lens?
A. Concave lens.
10. Draw the plane-concave mirror?
2 Marks
1. Preethi tells Sushant that the double convex lens behaves like a convergent lens. But Sushant knows that Preethi assertion is wrong and corrected Preethi by asking some questions. What are the questions asked by Sushant?
2. Draw a ray diagram for the following positions and explain the nature and position of image i) Object is placed at C2
ii) Object is placed between F2 and optic centre P?
3. A plane convex lens whose n=1.5 has a curved surface of radius 15cm what is its focal length? Why do you see a diminished image? How could this happen?
4.Write the steps involved in sign convention used in lenses?
4 Marks
1. Derive the formula of image formation in refraction at curved surfaces?
2. Derive the lens formula?
3. Derive the lens maker’s formula?
4. Write the experimental method and apparatus required in finding out the image formation using convex lens?
7. Human eye and
colourful world
1. The value of least distance of distinct vision is about?
a) 2.5cm b) 25cm
c) 100cm d) 2.277cm
2. The distance between the eye lens and retina is about
a) 2.5cm b) 25cm
c) 2.27cm d) 2cm
3. Change in the focal length of the eye lens is due to
a) iris b) cornea
c) ciliary muscles d) cones
4. Myopia can be corrected by using ____ lens.
a) Bi convex b) Bi concave
c) Plano convex d) Plano concave
5. Hypermetropia can be corrected by using ____ lens.
a) Bi convex b) Bi concave
c) Plano convex d) Plano concave
6. The splitting of white light into different colours is called
a) deviation b) dispersion
c) scattering d) refraction
7. The process of reemission of absorbed light in all directions with different intensities by atom or molecule is called ____ of light?
a) Scattering b) Dispersion
c) Reflection d) Refraction
8. ____ is the essential part of the eye act as a sensitive screen?
a) Cornea b) pupil
c) iris d) retina
9. ____ can relax and contract, there by adjusting the size of an aperture
a) iris b) pupil
c) yellow spot d) blind spot
10. The reason for the blue colour of sky is due to the molecules of ____ and ____.
a) H2O, CO2 b) N2, O2
c) O2, CO2 d) H2, O2
Answers
1) b; 2) a; 3) c; 4) b; 5) a; 6) b; 7) a; 8) d; 9) b; 10) b.
Important Questions
1 Mark
1. What are rods?
A. Rods are the receptors which identify the colour.
2. What is retina?
A. The retina is delicate membrane, which acts as a screen, the eye lens formula a real and inverted image of an object on the retina.
3. What are cones?
A. Cones are the receptors identify the intensity of light.
4. Which colour is best for school buses?
A. Yellow (or) Orange.
5. What is an optic nerve?
A. Optic nerve is nerve which transmit the light signals to the brain.
6. What type of lens used to correct myopia?
A. Bi concave.
7. State the role of ciliary muscles in accommodation?
A. It can adjust the focal length of the eye lens.
8. What is the function of pupil in human eye?
A. It allows the light falling on iris.
9. Write the formula of refractive index of the prism?
10. Name the molecules responsible for blue sky?
A. Nitrogen & oxygen molecules.
2 Marks
1. How do you appreciate the working of “iris”?
2. Have you seen a rainbow in the sky after rain? How is it formed?
3. Why the red signal is used for danger signals?
4. Why does the sky sometimes appear white?
5. Glass is known to be transparent material but ground glass is opaque and white in colour why?
6. A person is viewing an extended objects if a converging lens is placed in front of his eye, will he feel that the size of object has increased. Why?
4 Marks
1. Derive the formula for refractive index of a prism?
2. Write the different characteristics of red colour and violet colours in dispersion of light?
3. Explain briefly the reasons for the blue of the sky?
4. Write the experimental procedure of finding the refractive index of a prism?
5. Explain the formation of rainbow with the help of water drop diagram?
8. Structure of atom
1. Shape of s-orbital is
a) Spherical b) Dumbell
c) Square d) Double dumbell
2. Shape of p-orbital is
a) Double dumbell b) Dumbell
c) Spherical d) Circle
3. Shape of d-orbital is
a) Spherical
b) Dumbell c) Double dumbell
d) Square
4. In VIBGYOR which colour having higher wavelength or lower frequency?
a) Red b) Violet
c) Indigo d) Orange
5. Which of the following is not correct?
a) 2p6 b) 3s1
c) 2d3 d) 4f12
6. Stable elements
a) alkali b) alkalimetals
c) inert d) none
7. The subshell of the orbital for l = 1 is
a) s b) p c) d d) f
8. Short rotation of electron configuration is
a) nl x b) nl n c) ln x d) xn l
9. Splitting of spectral lines in the presence of electric field is called
a) Zeeman effect b) Stark effect
c) Dispersion d) Limen effect
10. What is ‘n’ value for L shell
a) 1 b) 2 c) 3 d) 4
Answers
1) a; 2) b; 3) c; 4) a; 5) c; 6) c; 7) b; 8) a; 9) b; 10) b.
Important Questions
1 Mark
1. Give the relation between c, u and l?
A. c = ul
2. Write the four quantum numbers for the differentiating electron of sodium (Na)?
A. n = 3, l = 0, m = 0, s = +½.or -½
3. What is the value of planks constant?
A. 6.625×10-27 erg sec (or) 6.625×10-34 Js
4. What is spectrum?
A. A group of frequencies (or) wave length is called spectrum.
5. Define Pauli exclusion principle?
A. No two electrons can have same four quantum numbers.
6. Draw the shape of s-orbital?
A. (Spherical)
7. Who proposed principle quantum number?
A. Niel’s Bohr.
8. What is Zeeman effect?
A. Splitting of spectral lines in presence of magnetic field is called Zeeman effect.
9. Write the electronic configuration of chromium?
A. 1s22s22p63s23p64s13d5
10. What is the shape of d-orbital?
A. Double dumbell.
2 Marks
1.Rainbow is an example for continuous spectrum explain? or Define continuous spectrum? Explain with one example?
2.How many elliptical orbits are added by sommerfeld in third bohr’s orbit? What was the purpose of adding these elliptical orbits?
3.Which rule is violated in the electronic configuration 1S0 2s2 2p4? (or) The following electronic configuration does not support the Aufbau principle Why 1S0 2s2 2p4?
4.write the four quantum numbers for the differentiating electrons of sodium atom? (or) Write the four quantum for the valence electron of sodium (Na) atom?
5.Write the four quantum numbers for 1S1 electron. (or) Write the four quantum numbers for hydrogen atom?
4 Marks
1. What are the postulates of Bohr atomic model? Write the defects on it?
2. In an atom the number of electrons in N. Shell is equal to the number of electrons in K and L and M shells. Answer the following questions?
(i) Which is the outer most shell?
(ii) How many electrons are there in its outermost shell.
(iii) What is the atomic number.
(iv) Write the electronic configuration of the elements.
3. How many elliptical orbits are added by sommerfeld in third Bohr’s orbit?
What was the purpose of adding these elliptical orbits?
4. Explain the significance of three quantum numbers in predicting the positions of an electron in an atom?
9. Classification of
elements –
The periodic table
1. Who proposed law of Octaves.
a) Dobereiner b) New Land
c) Bhor’s d) Mendeleeff
2. According Mendeleev physical and chemical properties of elements periodic functions of their ____ .
a) Atomic volume
b) Atomic weight
c) Atomic number
d) Electronic configuration
3. Predicted properties of Eka-Silicon is close to the observed property of
a) germanium b) Scandium
c) Gallium d) Sodium
4. 101th element was named as in honour of a scientist
a) Mendelevium b) Eisteinium
c) Rutherfordium d) Bohr
5. How many groups are present in long form of periodic table
a) 15 b) 16 c) 17 d) 18
6. General electronic configuration of Noble gases
a) ns1 b) ns2np5
c) ns2np6 d) ns2np6,nd5
7. Which period is in complete
a) 4 b) 7 c) 5 d) 6
8. 5f elements are called
a) Rare gases b) Actinides
c) Lanthanides d) None
9. 1 Pm =
a) 10-8m b) 10-10m
c) 10-12m d) 10-14m
10. The element with highest electronegativity is
a) F b) Cl c) Ca d) Ar
Answers
1) b; 2) b; 3) a; 4) a; 5) d; 6) c; 7) b; 8) b; 9) c; 10) a.
Important Questions
1 Mark
1. What are lanthanoids?
A. Elements from 58Ce to 71Lu are called Lanthanoids.
2. Write the name of the element family of 16 group?
A. Chalcogen family.
3. State Mendeleeff's periodic law?
A. The physical and chemical properties of the elements are the periodic functions of the their atomic weights.
4. What is the unit of ionization energy?
A. ev (or) K cal / mole (or) KJ/mole.
5. What are actinoids?
A. Elements from 90Th to 103Lr are called Actinoids.
6. Write the formula proposal by Milliken to measure electronegativity?
7.Give any two examples of Dobereiner’s traids?
A.Li, Na, K S, Se,Te
8.Write the electronic configuration of Transition elements?
A.ns2np6(n-1)d1-10
9.Write the Nobel gas elements?
A.He, Ne, Ar, Kr, Xe, Rn
10.Who is the father of periodic table?
A. Mendeleeff.
2 Marks
1.Name two elements that you would expect to have chemical properties similar to Mg. What is the basis for your choice?
2.An element has atomic number 19. Where would you expect this element in the periodic table and why?
3.Explain New Lands concept of octaves?
4.Second ionization energy of an element is higher than its first ionization energy why?
5. All alkali metals are solids but hydrogen is a gas with di atomic molecules. Do you justify the inclusion of Hydrogen in first group with alkali metals?
6. Why Mendeleeff had to leave certain blank spaces in his periodic table? What is your explanation for this?
4 Marks
1.Explain how the elements are classified into s, p, d, f in the Periodic
table and give the advantage of this kind of classifications?
2.What is a periodic property? How do the following properties change in a group and period? Explain?
(a) Atomic radius
(b) Ionization energy
(c) Electron affinity
(d) Electronegativity
3. What is Ionization energy? Explain the factors affect the ionization energy?
4. What are the limitations of Mendeleeff’s periodic table. How could the modern periodic table over come the limitations of Mendeleev’s table.
10. Chemical Bonding
1. Which of the following elements is electronegative?
a) sodium b) oxygen
c) magnesium d) calcium
2. An element forms an ionic compound with another element Y. then the charge on the ion formed by X- is
a) +1 b) +2 c) -1 d) -2
3. An element A forms chloride ACl4. The no. of electrons in the valence shell of A.
a) 1 b) 2 c) 3 d) 4
4. Bond angle in methane is
a) 170° b) 104.5
c) 109.281 d) 180º
5. Shape of ammonia molecule
a) Linear b) Angular
c) Pyramidal d) Tetra hydral
Answers
1) b; 2) a; 3) d; 4) c; 5) c.
Important Questions
1 Mark
1. General electronic configuration of noble gases?
A. ns2np6
2. What is the shape of Ammonia?
A. Pyramidal.
3. Give example for double bonded molecule?
A. O2, C2H4
4. Bond angle present in H2O molecule?
A. 104º. 311
5. Who proposed valance bond theory?
A. Linus Pauling.
6. Expand VSEPRT?
A. Valence – shell- electron – pair-repulsion-Theory.
7. Examples of non-pair solvents?
A. CCl4, C6H6, CS2
8. Write the Lewis dot structure of Ar?
A.
9. Examples of triple bond molecules?
A. N2, C2H2, HCN
10. Example of FCC molecule?
A. NaCl
2 Marks
1.Predict the reasons for low melting point of covalent compounds when compared with ionic compound?
2.Draw simple diagrams to show how electrons are arranged in the following covalent molecules?
a) Calcium oxide [CaO]
b) Water [H2O]
c) Chlorine [Cl2]
3.Draw the simple diagrams to show how electrons are arranged in the following covalent molecules?
a) Ammonia (NH3)
b) Methane (CH4)
4.Represent the lewis dot structure for the following?
He, Kr, Ne, Xe, Ar, Rn.
5.Represent each of the following atoms using lewis notation?
a) Berylium
b) Calcium c) Lithium
4 Marks
1.Explain what type bond is formed in AlCl3?
2.Explain VSEPRT theory?
3.What is hybridization? Explain the formation of the following molecules using hybridization?
(a) BeCl2 (b)BF3
4.Explain Lew’s approach to chemical bonding?
11. Electric Current
1.The magnitude of electric charge is ____ C
a) 1.602´10-19 b) 1.206´10-19
c) 1.062´10-19 d) None
2.The S.I unit of electric current
a) ampere b) coulomb
c) volts d) ohms
3.In the battery chemical energy is converted in to ____ Energy.
a) mechanical b) electrical
c) magnetic d) heat
4.The material which offers resistance to motion of electrons is called.
a) insulator b) conductor
c) resistor d) semi conductor
5.The S.I unit of resistance is ____ .
a) volt b) ohm
c) ampere d) joule
6.The S.I unit of Specific resistance (or) resistivity is ____.
a) ohm/metre b) ohm-metre
c) ohm d) ohm-metire
7.Specific resistance depends upon ____.
a) temperature
b) nature of material
c) length of material
d) a & b
8.Semi-conductors are used to make the following devices.
a) diodes b) transistors
c) integrated circuits
d) all of these
9.The obstruction to the flow of current is called ____.
a) current b) voltage
c) resistance d) none
10.The S.I unit of power ____.
a) volt b) ampere
c) watt d) kw
11.A thick wire has ____ resistance than a wire.
a) more b) less
c) equal d) none
12.The reciprocal of resistivity is called as…. a) Conductivity b) resistance
c) current d) voltage
Answers
1) a; 2) a; 3) b; 4) b; 5) b; 6) b; 7) d; 8) d; 9) c; 10) c; 11) b; 12) b.
Important Questions
1 Mark
1. What are the examples of non-ohmic conductors?
A. LED, Semiconductors.
2. Which material act as the best conductor?
A. Silver
3. How is power related to current and voltage?
A. P = V´I
4. A battery of 6v is applied across a resistance of 15W. Find the current flowing through the circuit?
A. 5. What do you mean by short circuit?
A. A sudden flow of a very large circuit due to direct current of live and neutral wire is called short circuit.
6. What is the shape of V-I shape for a metallic wire?
A. A straight line passing through origin.
7. Draw the symbol of Resistor?
A. 8. Define Resistivity?
A. Resistivity of the material is the resistance per unit length of a unit cross section of the material.
9. Define ohmic conductors?
A. The materials which obeys ohm’s law are called ohmic conductors.
10. Write the ohm’s law?
A. V=IR
2 Marks
1.What do you mean by electric shock? Explain how it takes place?
2.Why do we use fuses in household circuits?
3.Why should we connect the electric appliances in parallel to household circuit?
4. Explain the working of multimeter?
5. Define ohmic and non- ohmic conductors with examples?
4 Marks
1.State Ohm’s law. Suggest an experiment to verify it and explain the procedure?
2.What are the factors one which the resistance of conductor depends? Give the corresponding relation?
3.Derive the equation for resultant resistance of resistors in series combination?
4.Three resistors connect as shown in figure derive the equation for resultant resistance?
12. Electromagnetism
1.What converts electrical energy into mechanical energy
a) motor b) battery
c) generator d) switch
2. Which converts mechanical energy into electrical energy
a) motor b) battery
c) generator d) switch
3. The S.I unit of magnetic field induction is
a) Weber b) Weber/m2
c) Coulomb d) N/mt
4. Magnetic field is produced by the flow phenomenon was discovered by
a) coulomb b) oersted
c) faraday d) maxwell
5. Which of the following instruments works by electromagnetic induction?
a) dynamo
b) moving coil galvanometer
c) telephone receiver
d) simple motor
6. For making strong electromagnet, the material of the core should be
a) Brass b) laminated steel strips
c) soft iron d) steel
7. A device for producing electri
Wohler Friedrich.. German chemist who was a student of Berzelius. In attempting to prepare ammonium cyanate from silver cyanide and ammonium chloride, he accidentally synthesized urea in 1828. This was the first organic synthesis, and shattered the vitalism theory.
Electronic Configuration
Sodium (11) : 1s22s22p63s1
Potassium (19) : 1s22s22p63s23p64s1
Calcium (20) : 1s22s22p63s23p64s2
Iron (26) : 1s22s22p63s23p64s23d6
Chromium (24) : 1s22s22p63s23p64s13d5
Copper (29) : 1s22s22p63s23p64s13d10
Phosphrous (15) : 1s22s22p63s23p3
Nickel (28) : 1s22s22p63s23p64s23d8
Sulphur (16) : 1s22s22p63s23p4
Zinc (30) : 1s22s22p63s23p64s23d10
Physical Constants – Values
Specific heat of lead : 0.031Cal/g-Cº;130 J/Kg - k
Specific heat of Mercury : 0.033Cal/g-Cº; 139 J/Kg – k
Latent heat of fusion : 80 Cal / gm
Latent heat of Vaporization : 540 Cal / gm
Refractive Index of Diamond : 2.42
Refractive Index of Benzene : 1.50
Refractive Index of Quartz : 1.46
Scientists
Faraday : Laws of electrolysis.
Maxwell : Electron magnetic theory
J.J. Thomson : Watermelon model.
Rutherford : Planetory Model
Einstein : Laws of mass equivalence
Sommerfeld : Elliptical orbit model
Schrodinger : Wave equation
Maxplank : Quantum theory
Neils Bohr : Principle Quantum number
Ulenbeck & Goudsmith : Spin Quantum number
Dobereiner : Triad Theory
Sorensen : pH Scale
Newlands : Octave theory
Sumio Lijima : Nanotubes
Uses
Calorimeter : Determination of specific heat of substance.
Thermometer : Determination of Temperature
Prism : Observation of Angle of Dispersion.
pH paper : Observation of Acid – Base Strength.
Bleaching powder : Used as decolorizing agent, oxidant, used in preparation of chloroform, used in chlorination process.
Baking Soda : Manufacture of cakes, preparation of Antacid, preparation of Anti septic.
Washing Soda : Used in Glass, soap, paper industry preparation of borax, used to removal of hardness of water.
Galvanometer : Determination of electric current.
Electric motor : Convert the electric energy to mechanical energy.
Dynamo : Convert the mechanical energy to electric energy
Blast furnace : used to smelting process.
Voltmeter : Determine the potential difference.
Periodic Properties of Elements
Atomic Property In groups In period
(from top (from Left –
to bottom) Right)
Atomic size Increases Decreases
Ionization Potential Decreases Increases
Electron affinity Decreases Increases
Electro negativity Decreases Increases
Electro Positivity Increases Decreases
Oxidation Decreases Increases
Reduction Increases Decreases
Units
Specific heat : cal/g.cº (or) J/Kg-k.
Latent heat of fusion : Cal /gm (or) J/k.g
Power of lens : dioptres
Electric current : Ampere
Specific resistivity : Ohm-mt
Electric energy : KWH
Atomic Radius : Angstrom Unit (Aº)
Ionization potential : Electron Volt.
Chemical
Substances–Formulas
Substance : Formula
Bauxite : Al2O32H2O
Epsum salt : MgSO47H2O
Sinnabar : Hgs
Magnetite : Fe3O4
Galena : PbS
Carnalite : KClMgCl26H2O
Gypsum : CaSO4 2H2O
Pyrotusite : MnO2
Hypo : Na2S2O32H2O
Bleaching powder : CaOCl2
Plaster of Paris : CaSO4½H2O
Ethanol : C2H5OH
Ethyl Acetate : CH3COOC2H5
Soap : C17H35COONa
Zincite : ZnO
Lime stone : CaCO3
Horn silver : AgCl
Zinc Blende : ZnS
Rock Salt : NaCl
Hematite : Fe2O3
Different Solutions pH Values
Solution pH value
HCl 1
NaOH 13-14
Distilled water 7
Lemonjuice 2.5
Coffee 5
Carrot Juice 4
Soda Water 6
Tomato Juice 4.1
Saliva (before meal) 7.4
Saliva (after meal) 5.8
