# Maharashtra Board Class 10 Solutions General Science – Part 1

### Maharashtra Board Class 10 Solutions General Science – Part 1

Maharashtra Board Class 10 Important Question Chapter wise Download at here. Maharashtra Board Class 10 for General Science – Part 1. Maha Board Class 10th Textbook General Science – Part 1.

Maha Board Class 10th General Science – Part 1 Textbook All Questions. Maharashtra State Bureau of Textbook Production and Curriculum Research General Science – Part 1 Book Class 10.

 Book Type Text Book Class 10th Medium English Subjects General Science – Part 1 ### CHAPTER – 1 – Gravitation

(1) Study the entries in the following table and rewrite them putting the connected items in a single row.

 I II III Mass m/s2 Zero at the centre Weight kg Measure of inertia Accelera- tion due to gravity Nm2 /kg2 Same in the entire universe Gravita – tional con- stant N Depends on height

(a) What is the difference between mass and weight of an object. Will the mass and weight of an object on the earth be same as their values on Mars? Why?

(b) What are (i) free fall, (ii) acceleration due to gravity (iii) escape velocity (iv) centripetal force ?

(c) Write the three laws given by Kepler. How did they help Newton to arrive at the inverse square law of gravity?

(d) A stone thrown vertically upwards with initial velocity u reaches a height ‘h’ before coming down. Show that the time taken to go up is same as the time taken to come down.

(e) If the value of g suddenly becomes twice its value, it will become two times more difficult to pull a heavy object along the floor. Why?

(3) Explain why the value of g is zero at the centre of the earth.

(4) Solve the following examples.

(a) An object takes 5 s to reach the grond from a height of 5 m on a planet. What is the value of g on the planet?

(b) The radius of planet A is half the radius of planet B. If the mass of A is MA, what must be the mass of B so that the value of g on B is half that of its value on A?

(c) The mass and weight of an object on earth are 5 kg and 49 N respectively. What will be their values on the moon? Assume that the acceleration due to gravity on the moon is 1/6th of that on the earth.

(d) An object thrown vertically upwards reaches a height of 500 m. What was its initial velocity? How long will the object take to come back to the earth? Assume g = 10 m/s2

(e) A ball falls off a table and reaches the ground in 1 s. Assuming g = 10 m/s2 , calculate its speed on reaching the ground and the height of the table.

(f) The masses of the earth and moon are 6 x 1024 kg and 7.4×1022 kg, respectively. The distance between them is 3.84 x 105 km. Calculate the gravitational force of attraction between the two?

Use G = 6.7 x 10-11 N m2 kg-2

(g) The mass of the earth is 6 x 1024 kg. The distance between the earth and the Sun is 1.5x 1011 m. If the gravitational force between the two is 3.5 x 1022 N, what is the mass of the Sun?

Use G = 6.7 x 10-11 N m2 kg-2

### CHAPTER – 2 – Periodic Classification of Elements

(1) Rearrange the columns 2 and 3 so as to match with the column 1.

 Column 1 Column 2 Column 3 i. Triad ii. Octave iii.Atomic number iv. Period v. Nucleus vi. Electron a. Lightest and negatively charged particle in all the atoms b. Concentrated mass and positive charge c. Average of the first and the third atomic mass d. Properties of the eighth element similar to the first e. Positive charge on the nucleus f. Sequential change in molecular formulae 1. Mendeleev 2. Thomson 3. Newlands 4. Rutherford 5. Dobereiner 6. Moseley

(2) Choose the correct option and rewrite the statement.

(a) The number of electrons in the outermost shell of alkali metals is……

(i) 1 (ii) 2 (iii) 3 (iv) 7

(b) Alkaline earth metals have valency 2. This means that their position in the modern periodic table is in …..

(i) Group 2 (ii) Group16 (iii) Period 2 (iv) d-block

(c) Molecular formula of the chloride of an element X is XCl. This compound is a solid having high melting point. Which of the following elements be present in the same group as X.

(i) Na (ii) Mg (iii) Al (iv) Si

(d) In which block of the modern periodic table are the nonmetals found?

(i) s-block (ii) p-block (iii) d-block (iv) f-block

(3) An element has its electron configuration as 2,8,2. Now answer the following questions.

(a) What is the atomic number of this element?

(b) What is the group of this element?

(c) To which period does this element belong?

(d) With which of the following elements would this element resemble? (Atomic numbers are given in the brackets)

N (7), Be (4) , Ar (18), Cl (17)

(4) Write the name and symbol of the element from the description.

(a) The atom having the smallest size.

(b) The atom having the smallest atomic mass.

(c) The most electronegative atom.

(d) The noble gas with the smallest atomic radius.

(e) The most reactive nonmetal.

(5) Write short notes.

(a) Mendeleev’s periodic law.

(b) Structure of the modern periodic table.

(c) Position of isotopes in the Mendeleev’s and the modern periodic table.

(6) Write scientific reasons.

(a) Atomic radius goes on decreasing while going from left to right in a period.

(b) Metallic character goes on decreasing while going from left to right in a period.

(c) Atomic radius goes on increasing down a group.

(d) Elements belonging to the same group have the same valency.

(e) The third period contains only eight elements even through the electron capacity of the third shell is 18 .

(7) Write the names from the description.

(a) The period with electrons in the shellsK, L and M.

(b) The group with valency zero.

(c) The family of nonmetals having valency one.

(d) The family of metals having valency one.

(e) The family of metals having valency two.

(f) The metalloids in the second and third periods.

(g) Nonmetals in the third period.

(h) Two elements having valency 4.

### CHAPTER – 3 – Chemical Reactions and Equations

(1) Choose the correct option from the bracket and explain the statement giving reason.

(Oxidation, displacement, electrolysis, reduction, zinc, copper, double displacement, decomposition)

(a) To prevent rusting, a layer of …….. metal is applied on iron sheets.

(b) The conversion of ferrous sulphate to ferric sulphate is …….. reaction.

(c) When electric current is passed through acidulated water …….. of water takes place.

(d) Addition of an aqueous solution of ZnSO4 to an aqueous solution of BaCl2 is an example of ……. reaction.

(2) Write answers to the following.

(a) What is the reaction called when oxidation and reduction take place simultaneously? Explain with one example.

(b) How can the rate of the chemical reaction, namely, decomposition of hydrogen peroxide be increased?

(c) Explain the term reactant and product giving examples.

(d) Explain the types of reaction with reference to oxygen and hydrogen. Illustratre with examples.

(e) Explain the similarity and difference in two events, namely adding NaOH to water and adding CaO to water.

(3) Explain the following terms with examples.

(a) Endothermic reaction

(b) Combination reaction

(c) Balanced equation d. Displacement reaction

(4) Give scientific reasons.

(a) When the gas formed on heating limstone is passed through freshly prepared lime water, the lime water turns milky.

(b) It takes time for pieces of Shahabad tile to disappear in HCl, but its powder disappears rapidly.

(c)While preparing dilute sulphuric acid from concentrated sulphuric acid in the laboratory, the concentrated sulphuric acid is added slowly to water with constant stirring.

(d) It is reccommended to use air tight container for storing oil for long time.

### CHAPTER – 4 – Effects of electric current

(1) Tell the odd one out. Give proper explanation.

(a) Fuse wire, bad conductor, rubber gloves, generator.

( b) Voltmeter, Ammeter, galvanometer, thermometer.

(c) Loud speaker, microphone, electric motor, magnet.

(2) Explain the construction and working of the follwoing. Draw a neat diagram and label it.

(a) Electric motor

(b) Electric Generator(AC)

(3) Electromagnetic induction means-

(a) Charging of an electric conductor.

(b) Production of magnetic field due to a current flowing through a coil.

(c) Generation of a current in a coil due to relative motion between the coil and the magnet.

(d) Motion of the coil around the axle in an electric motor.

(4) Explain the difference : AC generator and DC generator.

(5) Which device is used to produce electricity? Describe with a neat diagram.

(a) Electric motor

(b) Galvanometer

(c) Electric Generator (DC) d. Voltmeter

(6) How does the short circuit form? What is its effect?

(7) Give Scientific reasons.

(a) Tungsten metal is used to make a solenoid type coil in an electric bulb.

(b) In the electic equipment producing heat e.g. iron, electric heater, boiler, toaster etc, an alloy such as Nichrome is used, not pure metals.

(c) For electric power transmission, copper or aluminium wire is used.

(d) In practice the unit kWh is used for the measurement of electrical energy, rather than joule.

(8) Which of the statement given below correctly describes the magnetic field near a long, straight current carrying conductor?

(a) The magnetic lines of force are in a plane, perpendicular to the conductor in the form of straight lines.

(b) The magnetic lines of force are parallel to the conductor on all the sides of conductor.

(c) The magnetic lines of force are perpendicular to the conductor going radially outword.

(d) The magnetic lines of force are in concentric circles with the wire as the center, in a plane perpendicular to the conductor.

(9) What is a solenoid? Compare the magnetic field produced by a solenoid with the magnetic field of a bar magnet. Draw neat figures and name various components.

(10) Solve the following example.

(a) Heat energy is being produced in a resistance in a circuit at the rate of 100 W. The current of 3 A is flowing in the circuit. What must be the value of the resistance?

(b) Two tungsten bulbs of wattage 100 W and 60 W power work on 220 V potential difference. If they are connected in parallel, how much current will flow in the main conductor?

(c) Who will spend more electrical energy? 500 W TV Set in 30 mins, or 600 W heater in 20 mins?

(d) An electric iron of 1100 W is operated for 2 hrs daily. What will be the electrical consumption expenses for that in the month of April? (The electric company charges Rs 5 per unit of energy).

### CHAPTER – 5 – Heat

(1) Fill in the blanks and rewrite the sentence.

(a) The amount of water vapor in air is determined in terms of its …………

(b) If objects of equal masses are given equal heat, their final temperature will be different. This is due to difference in their ………………

(c) During transformation of liquid phase to solid phase, the latent heat is ………….

(3) What is meant by specific heat capacity? How will you prove experimentally that different substances have different specific heat capacities?

(4) While deciding the unit for heat, which temperatures interval is chosen? Why?

(5) Explain the following:

(a) What is the role of anomalous behaviour of water in preserving aquatic life in regions of cold climate?

(b) How can you relate the formation of water droplets on the outer surface of a bottle taken out of refrigerator with formation of dew?

(c) In cold regions in winter, the rocks crack due to anomolous expansion of water.

(a) What is meant by latent heat? How will the state of matter transform if latent heat is given off?

(b) Which principle is used to measure the specific heat capacity of a substance?

(c) Explain the role of latent heat in the change of state of a substances? d. On what basis and how will you determine whether air is saturated with vapor or not?

If heat is exchanged between a hot and cold object, the temperature of the cold object goes on increasing due to gain of energy and the temperature of the hot object goes on decreasing due to loss of energy. The change in temperature continues till the temperatures of both the objects attain the same value. In this process, the cold object gains heat energy and the hot object loses heat energy. If the system of both the objects is isolated from the environment by keeping it inside a heat resistant box (meaning that the energy exchange takes place between the two objects only), then no energy can flow from inside the box or come into the box.

(i) Heat is transferred from where to where?

(ii) Which principle do we learn about from this process?

(iii) How will you state the principle briefly? iv. Which property of the substance is measured using this principle?

(8) Solve the following problems:

(a) Equal heat is given to two objects A and B of mass 1 g. Temperature of A increases by 3 o C and B by 5 o C. Which object has more specific heat? And by what factor?

(b) Liquid ammonia is used in ice factory for making ice from water. If water at 20 o C is to be converted into 2 kg ice at 0 o C, how many grams of ammonia are to be evaporated? (Given: The latent heat of vaporization of ammonia= 341 cal/g)

(c) A thermally insulated pot has 150 g ice at temperature 0 oC. How much steam of 100 oC has to be mixed to it, so that water of temperature 50 o C will be obtained? (Given : latent heat of melting of ice = 80 cal/g, latent heat of vaporization of water = 540 cal/g, specific heat of water = 1 cal/g 0C)

(d) A calorimeter has mass 100 g and specific heat 0.1 kcal/ kg oC. It contains 250 gm of liquid at 30 oC having specific heat of 0.4 kcal/kg o C. If we drop a piece of ice of mass 10 g at 0 oC, What will be the temperature of the mixture?

### CHAPTER – 6 – Refraction of light

(1) Fill in the blanks and Explain the completed sentences.

(a ) Refractive index depends on the …………. of light.

(b) The change in ……………. of light rays while going from one medium to another is called refraction.

(2) Prove the following statements.

(a) If the angle of incidence and angle of emergence of a light ray falling on a glass slab are i and e respectively, prove that, i = e.

(b) A raibow is the combined effect of the refraction, dispersion, and total internal reflection of light.

(3) Solve the following examples.

(a) If the speed of light in a medium is 1.5 x 108 m/s, what is the absolute refractive index of the medium?

(b) If the absolute refractive indices of glass and water are 3/2 and 4/3 respectively, what is the refractive index of glass with respect to water?

### CHAPTER – 7 – Lenses

(1) Match the columns in the following table and explain them.

 Column 1 Column 2 Column 3 Farsightdness Nearby object can be seen clearly Bifocal lens Presbyopia Far away object can be seen clearly Concave lens Nearsightness Problem of old age Convex lens

(2)  Draw a figure explaining various terms related to a lens.

(3) At which position will you keep an object in front of a convex lens so as to get a real image of the same size as the object ? Draw a figure.

(4) Give scientific resons:

(a) Simple microscope is used for watch repairs.

(b) One can sense colours only in bright light.

(c) We can not clearly see an object kept at a distance less than 25 cm from the eye.

(5) Explain the working of an astronomical telescope using refraction of light.

(6) Distinguish between:

(a) Farsightedness and Nearsightedness

(b) Concave lens and Convex Lens

(7) What is the function of iris and the muscles connected to the lens in human eye?

(8) Solve the following examples.

(i) Doctor has prescribed a lens having power +1.5 D. What will be the focal length of the lens? What is the type of the lens and what must be the defect of vision?

(ii) 5 cm high object is placed at a distance of 25 cm from a converging lens of focal length of 10 cm. Determine the position, size and type of the image.

(iii) Three lenses having power 2, 2.5 and 1.7 D are kept touching in a row. What is the total power of the lens combination?

(iv) An object kept 60 cm from a lens gives a virtual image 20 cm in front of the lens. What is the focal length of the lens? Is it a converging lens or diverging lens?

### CHAPTER – 8 – Metallurgy

(1) Write names.

(a) Alloy of sodium with mercury.

(b) Molecular formula of the common ore of aluminium.

(c) The oxide that forms salt and water by reacting with both acid and base.

(d) The device used for grinding an ore.

(e) The nonmetal having electrical conductivity.

( f) The reagent that dissolves noble metals.

(2) Explain the terms.

(a) Metallurgy

(b) Ores

(c) Minerals

(d) Gangue.

(3) Write scientific reasons.

(a) Lemon or tamarind is used for cleaning copper vessels turned greenish.

(b) Generally the ionic compounds have high melting points.

(c) Sodium is always kept in kerosene.

(d) Pine oil is used in froth flotation.

(e) Anodes need to be replaced from time to time during the electrolysis of alumina.

(4) When a copper coin is dipped in silver nitrate solution, a glitter appears on the coin after some time. Why does this happen? Write the chemical equation.

(5) The electronic configuration of metal ‘A’ is 2,8,1 and that of metal ‘B’ is 2,8,2. Which of the two metals is more reactive? Write their reaction with dilute hydrochloric acid.

(6) Draw a neat labelled diagram.

(a) Magnetic separation method.

(b) Froth floatation method.

(c) Electrolytic reduction of alumina.

(d)Hydraulic separation method.

(7) Write chemical equation for the following events. a. Aluminium came

(a) Aluminium came in contact with air.

(b) Iron filings are dropped in aqueous solution of copper sulphate.

(c) A reaction was brought about between ferric oxide and aluminium.

(d) Electrolysis of alumina is done. e. Zinc oxide is dissolved in dilute hydrochloric acid

(8) Complete the following statement using every given options. During the extraction of aluminium…………..

(a)Ingredients and gangue in bauxite.

(b)Use of leaching during the concentration of ore.
(c) Chemical reaction of transformation of bauxite into alumina by Hall’s process.

(d)Heating the aluminium ore with concentrated caustic soda.

(9) Divide the metals Cu, Zn, Ca, Mg, Fe, Na, Li into three groups, namely reactive metals, moderately reactive metals and less reactive metals.

### CHAPTER – 9 – Carbon Compounds

(1) Explain the following terms with example.

(a) Structural isomerism

(b) Covalent bond

(c) Hetero atom in a carbon compound

(d) Functional group

(e) Alkane

(f) Unsaturated hydrocarbon

(g) Homopolumer

(h) Monomer

(i) Reduction

(j) Oxydant

(a) What causes the existance of very large number of carbon compound ?

(b) Saturated hydrocarbons are classified into three types. Write these names giving one example each.

(c) Give any four functional groups containing oxygen as the heteroatom in it. Write name and structural formula of one example each.

(d) Give names of three functional groups containing three different hetero atoms. Write name and structural formula of one example each.

(e) Give names of three natural polymers. Write the place of their occurance and names of monomers from which they are formed.

(f) What is meant by vinegar and gashol? What are their uses ?

(g) What is a catalyst ? Write any one reaction which is brought about by use of catalyst ?

### CHAPTER – 10 – Space Missions

(1) Fill in the blanks and explain the statements with reasoning:

(a) If the height of the orbit of a satellite from the earth surface is increased, the tangential velocity of the satellite will …

(b) The initial velocity (during launching) of the Managalyaan, must be greater than …………..of the earth.

(2) State with reasons whether the following sentences are true or false

(a) If a spacecraft has to be sent away from the influence of earth’s gravitational field, its velocity must be less than the escape velocity.

(b) The escape velocity on the moon is less than that on the earth.

(c) A satellite needs a specific velocity to revolve in a specific orbit.

(d) If the height of the orbit of a satellite increases, its velocity must also increase.

(a) What is meant by an artificial satellite? How are the satellites classified based on their functions?

(b) What is meant by the orbit of a satellite? On what basis and how are the orbits of artificial satellites classified?

(c) Why are geostationary satellites not useful for studies of polar regions?

(d) What is meant by satellite launch vehicles? Explain a satellite launch vehicle developed by ISRO with the help of a schematic diagram.

(e) Why it is beneficial to use satellite launch vehicles made of more than one stage?

(4) Solve the following problems.

(a) If mass of a planet is eight times the mass of the earth and its radius is twice the radius of the earth, what will be the escape velocity for that planet?

(b) How much time a satellite in an orbit at height 35780 km above earth’s surface would take, if the mass of the earth would have been four times its original mass?

Updated: February 12, 2019 — 12:57 pm