8881 + Interview Questions in Chemistry in Class 10 Page 134 InterviewSolution

6651.	Define electronegativity .
Answer» SOLUTION :Electronegativity of an element is the measureof the TENDENCY of its atoms to attract the SHARED pairof ELECTRONS towardsitselfin a covalent bond .

Discussion

6652.	Define Electron affinity.
Answer» SOLUTION : Electron AFFINITY is the amount of energy RELEASED when a gaseous atom gains an electron to form its anion.It is also measured in KJ / mol

Discussion

6653.	Define electron affinity .
Answer» Solution :ELECTRON affinity is the amount of energyreleasedwhen a gaseousatom gainsan electron to FORM its ANION . `A_((g))+E^(-)to A_((g))^(+) +`ENERGY `Cl_((g))+e^(-) to Cl_((g))^(-)+`energy

Discussion

6654.	What is the achievement of Doberiner's law of triads ?
Answer» Solution :It states “whenelements are placedinorder of the ascending order of ATOMIC masses,groups of three ELEMENTS havingsimilar properties are obtained.The atomic MASS of the middle element of the triad is EQUAL to the mean of the atomic masses of the other TWO elements of the traid”

Discussion

6655.	Define -Displacement reaction.Give example.
Answer» Solution :The reaction in which a more reactive ELEMENT diplaces a less reactive element from its compound is CALLED DISPLACEMENT reaction. `Pb+CuCl_(2)toPbCl_(2)+Cudarr` Lead displaces copper from copper CHLORIDE solution.

Discussion

6656.	Define discharge potential. Draw a comparison with the standard reduction potential (SRP) value of elements in the electrochemical series.
Answer» Solution :The ACTUAL POTENTIAL required for the discharge of ion at the electrode is called discharge potential. In case of positive IONS, higher SRP value INDICATES lower discharge potential as positive ions get discharged at the electrode by gaining electrons (reduction) In case of negative ions, higher standard oxidation potential value (lower SrP value) indicates lower discharge potential as negative ions get discharged at the electrode by LOSING electrons (oxidation)

Discussion

6657.	Definedisplacement reaction
Answer» SOLUTION :A reaction in which more REACTIVE metal displaces LESS reactive metal from its compound in solution or in MOLTEN FORM is known as displacement reaction.

Discussion

6658.	Define dilution.
Answer» SOLUTION :Mixing an acid or base with water results in decrease in the CONCENTRATION of IONS per unit volume. Such a process is CALLED DILUTING and the acid or the base is said to be dilutioned.

Discussion

6659.	Define covalentradius .
Answer» Solution :Covalentradius is defined as halfthe distancebetween THENUCLEI of TWO covalently bonded ATOMS of the same element in a MOLECULE .

Discussion

6660.	Define : Covalent bond
Answer» Solution :A CHEMICAL bond FORMED between two or more atoms by mutual sharing of valence electrons is KNOWN as a COVALENT bond.

Discussion

6661.	DefineCorrosion
Answer» Solution :Metal gets RUSTED, when it is exposed to water, air and moisture for LONG TIME. This process of rusting is KNOWN as metal corrosion.

Discussion

6662.	Definecorrosion .
Answer» Solution :(i) It is the gradual destrution of metals by chemical or electrochemical reaction with the environment . (II) It is a natural processwhich converts a METAL into its oxide , hydroxide or sulphideso that it loses its metalliccharacteristics .

Discussion

6663.	Define : Combustion reaction
Answer» Solution :CARBON (or most of the organic compounds), in all its allotropic forms, burns in air to give carbon DIOXIDE along with the release of heat and light. This is CALLED COMBUSTION REACTION.

Discussion

6664.	Define combination reaction.Give one example for an exothermic combination reaction.
Answer» Solution :A CHEMICAL reaction in which 2 or more reactants combine to form a single product ,the reaction is KNOWN as combination reaction.Most of the combination reaction are exothermic because `H_(2(g))+Cl_(2(g))to2HCl_((g)),SiO_(2)+CaO_((s))toCaSiO_(3(s))`

Discussion

6665.	Define : Catenation
Answer» Solution :Carbon has the unique ability to form bonds with other atoms of carbon, GIVING RISE to a large number of molecules. This PROPERTY of carbon is CALLED catenation.

Discussion

6666.	Define catalyst.
Answer» Solution : A substance which ALTERS the RATE of reaction withour undersgoing any change in MASS and composition is known as CATALYST.

Discussion

6667.	Define calcination and write its purpose.
Answer» Solution :Heating of an ORE of a metal in the absence of air is CALLED CALCINATION. It is employed to CONVERT a CARBONATE ore of a metal into its oxide.

Discussion

6668.	DefineCalcination
Answer» SOLUTION :The process of STRONGLY heating carbonate ores in limited air, so that the volatile impurities are REMOVED CONVERTING ores into oxides is called calcination.

Discussion

6669.	Define Avogadro number.
Answer» Solution :The ACTUAL NUMBER of atoms in 12 G of carbon-12 is called Avogadro number. It is equal to `6.023xx10^(23)(N_(A))`.

Discussion

6670.	Defineaverageatomicmass (AAM ).
Answer» SOLUTION :The AVERAGE ATOMICMASS of an ELEMENTIS theweighted averageof massesof itsnaturallyoccurringisotopes .

Discussion

6671.	Define Atomicity.
Answer» SOLUTION :The NUMBER of ATOMS present in the molecule is called its .ATOMICITY..

Discussion

6672.	Define : Atomic radius
Answer» SOLUTION :The distance between the CENTRE of the nucleus and the outermost shell of an isolated ATOM is CALLED atomic RADIUS.

Discussion

6673.	Define atomic radius.
Answer» Solution :Atomicradiusof an tom is DEFINED as the DISTANCE between the CENTREOF its nucleusand the OUTERMOST shell containingthe valenceelectron .

Discussion

6674.	Defineatomicmassunit(amu ).
Answer» SOLUTION :Oneatomicmass unitdefinedas `(1)/(12^(TH))`partofthe MASSOF oneatomofcarbon .

Discussion

6675.	Define atomic mass unit u.
Answer» SOLUTION :Atomicmassunitis ONE- Twelfthof massofcarbon- 12atom , anisotopeof CARBON , whichcontains6protonsand6neutrons.

Discussion

6676.	Define atomic mass unit.
Answer» SOLUTION :ATOMIC mass unit is one-twelfth of the mass of CARBON-12 atom, as an isotope of carbon which CONTAINS 6 protons and 6 NEUTRONS. It is amu.

Discussion

6677.	Define anode-mud
Answer» Solution : In ELECTROLYTIC refining, INSOLUBLE impurities such as gold, silver, platinum are SETTLED at the bottom of the anode are KNOWN as an anode-mud.

Discussion

6678.	Define and show in a diagram, the following terms relating to concave mirrors. i) Aperture ii) Radius of curvature List any four uses of concave mirror.
Answer» SOLUTION :i) The diameter of the reflecting surface of the mirror is called aperature . ii) The radius of the SPHERE of which reflecting surface of the spherical mirror forms a part is called the radius of curvature of the spherical mirror. Uses of concave mirror are : `` SHAVING mirror `` Reflectors in automobile head light and TORCHES `` By dentists to see back side of tooth. `` Reflector of solar furnaces.

Discussion

6679.	Define an alloy. How are alloys prepared ? How do the properties of iron change when : (i) small quantity of carbon is mixed ? (ii) nickel and chromium are mixed with it ?
Answer» SOLUTION :Alloy is a homogeneous mixture of two or more metals and non-metals. It is PREPARED by first melting the primary metal and then dissolving the other elements in it definite proportion. It is then cooled at ROOM temperature. (i) On mixing carbons, it BECOMES hard and strong. (ii) On mixing Ni and Cr, it becomes hard and does not rust.

Discussion

6680.	Define an acid in terms of ions.
Answer» SOLUTION :An ACID GIVES `H^(+)` ION

Discussion

6681.	Define amphoteric oxides. Give two examples of such oxides.
Answer» Solution :Amphoteric OXIDES : Oxides which SHOW both ACIDIC and basic behaviour and oxides that REACT with both acids as well as bases to produce salts and water. Example : `Al_(2)O_(3)` and ZnO.

Discussion

6682.	Define alloys. List the properties of alloys that make them useful over pure metals ? Explain this fact with suitable examples.
Answer» Solution :ALLOYS are homogeneous mixture of TWO or more metals or a metal and a non-metal that cannot be separated into their components by physical methods. The properties that make them useful over metal are (i) The electrical conductivity (ii) Melting point of an ALLOY is LESS than that of a pure metal. e.g. Brass and Bronze are not good conductors of electricity whereas copper is used in MAKING electrical circuit. e.g., Solder has a low melting point.

Discussion

6683.	Define alloy
Answer» SOLUTION :The HOMOGENOUS MIXTURE of two or more metals, or a metal and a non-metal is called an ALLOY

Discussion

6684.	Define : Addition reaction
Answer» Solution :The REACTION in which unsaturated HYDROCARBONS add hydrogen in the PRESENCE of catalysts such as palladium or NICKEL to form saturated hydrocarbons is CALLED an addition reaction.

Discussion

6685.	Define accommodation of an eye ?
Answer» SOLUTION :The ABILITY of the eye to focus both near and DISTANT objects by adjusting the FOCAL LENGTH is callod accommodation of the eye.

Discussion

6686.	Define a universal indicator. Mention its one use.
Answer» SOLUTION :A UNIVERSAL indicator is a mixture of several indicators. It shows different COLOURS at different CONCENTRATIONS of `H^+` ION concentrations.

Discussion

6687.	Define a period of the modern periodic table of elements.
Answer» SOLUTION :PERIOD is a horizontal row of ELEMENTS STARTING with an alkali metal and ending with a noble gas.

Discussion

6688.	MIXTURE
Answer» Solution :A MIXTURE is formed from ELEMENTS and/or COMPOUNDS mixed in any proportion. It MAY be homgogenous or heterogeneous.

Discussion

6689.	Define a homologous series of carbon compounds, List any two characteristics of a homologous series.
Answer» SOLUTION : A homologous series is a series of compounds with the same functional GROUP and similar CHEMICAL properties in which each successive member differs by `CH_2`. This can be ALONG the length of a carbon chain. The characteristics of any homologous series are: a] Their members have similar chemical properties as they have same functional group. b] Their members have the same GENERAL formula.

Discussion

6690.	Define a combination reaction. Give one example of a combination reaction which is exothermic.
Answer» Solution :Reaction where two or more REACTANTS combine TOGETHER to yield a single PRODUCT. `CaO(s)+H_(2)O(l)toCa(OH)_(2)(s)"Energy"`.

Discussion

6691.	Define a chemical reaction. Which observation help you to determine whether a chemical reaction has taken place ?
Answer» SOLUTION :CHEMICAL REACTION

Discussion

6692.	Define a chemical reaction . State four observations which help us to determine that a chemical reaction has taken place. Write one example of each observation with a balanced chemical equation.
Answer» Solution :Process in which new substances with new properties are formed by the rearrangement of atoms is known as CHEMICAL reaction. (i) Evolution of gas : The chemical reaction between zinc and DILUTE `H_(2)SO_(4)` `Zn(S)+H_(2)SO_(4) (aq) RARR ZnSO_(4)(aq)+H_(2)(g)` (II) Change in colour : thechemical reaction between potassium iodide solution and lead nitrate solution. ` underset (("Colourless"))(Pb(NO_(3))_(2)(aq))+2Klrarr2KNO_(3)(aq)+ underset (("Yellow"))(PbI_(2)(s))` (iii) FORMATION of precipitate : The chemical reaction between sulphuric and barium chloride solution. `BaCl_(2)(aq)+H_(2)SO_(4)(aq)rarr2HCl(aq)+underset(("White precipitate"))(BaSO_(4)(S))` (iv) Change in temperature : The chemical reaction between quick lime and water . `underset (("Quicklime"))CaO(S)+H_(2)O(l)rarrCa(OH)_(2)(aq)+"Heat"`

Discussion

6693.	Define a chemical equation.
Answer» SOLUTION :A chemical EQUATION is a symbolic representation of a chemical REACTION written using chemical symbols for reactants, products, and also indicating the conditions required for the reaction to take PLACE.

Discussion

6694.	Defect is caused due to
Answer» REGULAR arrangement Irregular arrangement Cations have regular WHEREAS ANIONS have irregular All of the above Answer :B

Discussion

6695.	Deduce the maximum electron capacity of the shells K, L and M?
Answer» SOLUTION :K -2 `(2n^2 = 2 xx 1^2 = 2)` L -8 `(2n^2 = 2 xx 2^2 = 2 xx 4 = 8)` M -18 `(2n^2 = 2 xx 3^2 = 2 xx 9 = 18)`

Discussion

6696.	Decomposition reactions are used to extract some metals from their oxides.
Answer» ANSWER :T

Discussion

6697.	Decomposition reactions require energy either in the form of heat or light or electricity for breaking down the reactants. Write one equation each for decomposition reactions where energy is supplied in the form heat, light and electricity.
Answer» Solution :Decomposition of FERROUS sulphate `underset("Ferrous sulphate")(2FeSO_(4))(s)overset("Heat")(to)underset("Ferric oxide")(Fe_(2)O_(3))(s)+SO_(2)(g)+SO_(3)(g)` Energy supplied in the form of light : Decomposition of silver CHLORIDE `2AgCl(s)overset("Sunlight")(to)2AG(s)+Cl_(2)(g)` Energy supplied in the form of electricity : ELECTROLYSIS of water `2H_(2)O overset("Electricity")(to)2H_(2)(g)+O_(2)(g)`

Discussion

6698.	Decomposition reaction requires energy in the form of heat or light or electricity for breaking the reactants. Write one example for each with equation.
Answer» SOLUTION :Decomposition of calcium CARBONATE by heating : `CaCO_(3)(g)overset("heat")(to)CaO(s)+CO_(2)(g)` Decomposition of silver BROMIDE by the USE of sunlight : `2AgBr(s)overset("sunlight")(to)2Ag(s)+Br_(2)(g)` Decomposition of water by ELECTRICITY : `2H_(2)O(l)overset("electrolysis")(to)2H_(2)(s)+O_(2)(g)`

Discussion

6699.	Decompositionreactionis theoppositeof _______ reaction .
Answer» SOLUTION :COMBINATION

Discussion

6700.	Decomposition of water takes place by
Answer» HEATING by SUNLIGHT MELTING by ELECTRICITY ANSWER :D

Discussion

Explore topic-wise InterviewSolutions in .

Define electronegativity .

Define Electron affinity.

Define electron affinity .

What is the achievement of Doberiner's law of triads ?

Define -Displacement reaction.Give example.

Define discharge potential. Draw a comparison with the standard reduction potential (SRP) value of elements in the electrochemical series.

Definedisplacement reaction

Define dilution.

Define covalentradius .

Define : Covalent bond

DefineCorrosion

Definecorrosion .

Define : Combustion reaction

Define combination reaction.Give one example for an exothermic combination reaction.

Define : Catenation

Define catalyst.

Define calcination and write its purpose.

DefineCalcination

Define Avogadro number.

Defineaverageatomicmass (AAM ).

Define Atomicity.

Define : Atomic radius

Define atomic radius.

Defineatomicmassunit(amu ).

Define atomic mass unit u.

Define atomic mass unit.

Define anode-mud

Define and show in a diagram, the following terms relating to concave mirrors. i) Aperture ii) Radius of curvature List any four uses of concave mirror.

Define an alloy. How are alloys prepared ? How do the properties of iron change when : (i) small quantity of carbon is mixed ? (ii) nickel and chromium are mixed with it ?

Define an acid in terms of ions.

Define amphoteric oxides. Give two examples of such oxides.

Define alloys. List the properties of alloys that make them useful over pure metals ? Explain this fact with suitable examples.

Define alloy

Define : Addition reaction

Define accommodation of an eye ?

Define a universal indicator. Mention its one use.

Define a period of the modern periodic table of elements.

MIXTURE

Define a homologous series of carbon compounds, List any two characteristics of a homologous series.

Define a combination reaction. Give one example of a combination reaction which is exothermic.

Define a chemical reaction. Which observation help you to determine whether a chemical reaction has taken place ?

Define a chemical reaction . State four observations which help us to determine that a chemical reaction has taken place. Write one example of each observation with a balanced chemical equation.

Define a chemical equation.

Defect is caused due to

Deduce the maximum electron capacity of the shells K, L and M?

Decomposition reactions are used to extract some metals from their oxides.

Decomposition reactions require energy either in the form of heat or light or electricity for breaking down the reactants. Write one equation each for decomposition reactions where energy is supplied in the form heat, light and electricity.

Decomposition reaction requires energy in the form of heat or light or electricity for breaking the reactants. Write one example for each with equation.

Decompositionreactionis theoppositeof _______ reaction .

Decomposition of water takes place by