8881 + Interview Questions in Chemistry in Class 10 Page 97 InterviewSolution

4801.	In the long form of periodic table the total number of groups are
Answer» 15 18 12 8 Solution :There are 18 VERTICAL COLUMNS in the periodic table called GROUPS Group `1TO` ALKALI metals Group `17to` halogens Group `18to` noble gases

Discussion

4802.	In the hydrocarbon HC -= C -H,the covalency of carbon is
Answer» one two three four Solution :`H - C -= C - H`, ach carbon ATOM has formed from COVALENT bond, hence, covalency of each C atom is 4.

Discussion

4803.	In the Hall's process , cathode used is ………… .
Answer» Iron tank GRAPHITE Pure ALUMINA Iron tank linked with graphite ANSWER :D

Discussion

4804.	In the given figure of Cotyledon the parts labelled as A and B respectively are
Answer» fruit, shoot PRIMARY shoot, primary root secondary root, primary shoot bud, leaf. Solution :LN the given FIGURE of cotyledon the parts LABELLED as A and 8 respectivdy are : (B) primary shoot, primary root

Discussion

4805.	In thefraph given below, identify the states of solution atthevarious points A, B, C and E.If thesolution is cooled from point 'A' at which temperature, precipitation normally starts ? Also, find out theamount of solute precipitated at 40^(@)C at A and the amount of solute in thesolution at point 'E'. What would be themaximum amount of solute that can be precipitated in the process?
Answer» Solution :Thecurve indicates that thesolubility of thesolute at `100^(@)C` is 250 g. However, the given solution contains only 150 g of solute. THESOLUTION atpoint 'A' is an unsaturated solution. Therefore, no precipitation takes place up topoint 'B' at `60^(@) C`, where thesolution becomes saturated, withjust 150 gas SOLUBILITY. Point 'B'indicates saturated solution andhence, precipitations normally starts at `60^(@)C`. With the fall intemperature, solubility decreases andthe extra amount should get precipitated: Point 'C' at `40^(@)C` indicates that the solution still contained 150 g of solute, whichis a supersaturated solution. THATMEANS, it is possible to cool a solution from `60^(@)C" to" 40^(@)C` without any crystallisation by creating conditions such as absence ofdust particles. At `40^(@)C`, when crystallisation starts, thesolution ULTIMATELY becomes saturated , and this is represented by point D.At pointD (`40^(@)C`), thesolubility is 100 g . That means, 50 g of solute would havebeen precipitated. At 'E' also thesolution remains saturated by precipitating 25 g more ofsolute leaving behing 75 g of solute in the solution. At `0^(@)C`, when water starts to solidify, thesolution still contains 5 g ofsolute without precipitation. That means, 125 g of solute can be precipitated.

Discussion

4806.	In the formation of the compound XY, atoms of X lost one electrons each while atoms of Y gained one electron each. What is the nature of bond in XY? Predict the two properties of XY.
Answer» Solution :The atoms of X lose electrons whereas the atoms of Y GAIN electrons. Thus, there is TRANSFER of electrons from atoms of X to atoms of Y. The bond formed by the transfer of electrons is CALLED ionic bond. THEREFORE, the nature of bond in the compound XY is ionic. Properties of ionic compound XY: (i) The compound will be soluble in water. (ii) The compound will CONDUCT electricity when dissolved in water or in molten state.

Discussion

4807.	In the formation of nitrogen molecule.
Answer» ONE PAIR of ELECTRONS are SHARED two PAIRS of electrons are shared. three pairs of electrons are shared. four pairs of electrons are shared Solution :`N::N`, Three pairs of electrons are shared.

Discussion

4808.	In the formation of a compound XY_2, atom X donates one electron to each Y atom. Show theelectron dot structure of X and Y and the formation of XY_2 . What is the nature of bond in XY, ? Write any three properties of compound XY_2 . The electronic configurations of the elements X and Y are as follows:X-2,8,2Y-2,7
Answer» Solution : The nature of bonds in `XY_2`is ionic. Properties : (i) Ionic compounds have high MELTING and boiling points. (ii) Ionic compounds are generally soluble in WATER and insoluble in KEROSENE and petrol. (III) Solutions of ionic compounds conduct electricity. Molten STATE of such compounds also conductelectricity.

Discussion

4809.	In the following table, the positions of six elements A, B, C, D, E and F are given as they are in the Modern Periodic Table: On the basis of the above table, answer the following questions:(i) Name the element which forms only covalent compounds. (ii) Name the element which is a metal with valency three. (iii) Name the element which is a non-metal with valency three. (iv) Out of B and C, whose atomic radius is bigger and why? (v) Write the common name for the family to which the elements D and F belong.
Answer» Solution : (i) E(II) B(iii) C (IV) B, because atomic radius decreases from left to right due to INCREASE in the nuclear charge.(v) Noble gases

Discussion

4810.	In the following table, the positions of six elements A, B, C, D, E and F are given as they are in the Modern Periodic Table : On the basis of the above table, answer the following questions : (i) Name the element which forms only covalent compounds. (ii) Name the element which is a metal with valency three. (iii) Name the element which is a non-metal with valency three. (iv) Out of B and C, whose atomic radius is bigger and why? (v) Write the common name for the family to which the elements D and F belong.
Answer» Solution :(i) E (II) B (iii) C (iv) B, because ATOMIC RADIUS decreases from left to right DUE to increase in the nuclear charge. (V) Noble gases.

Discussion

4811.	In the following table, six elements A, B, C, D, E and F of the modern periodic table with atomic numbers 3 to 18 are given: (a) Which of these is (i) Noble gas (ii) halogen? (b) Which of these is the most active metal in 3rd period? (c) Identify the most electronegative element in the third period. (d) In the compound between B and F what type of bond will be formed? (e) What would be the nature of oxide formed by C?
Answer» Solution :(a) NOBLE GAS - GHalogen - F (b)Most active metal – B (c) Most electronegative in 3rd period - F (d) Ionic bond (e) Oxide formed by C would be BASIC.

Discussion

4812.	In the following schematic diagram for the preparation of hydrogen gas as shown in figure, what would happens if the following changes are made? (a) In place of zinc granules. Same amount of zinc dust is taken in the test tube. (b) Instead of dilute sulphuric acid, dilute hydrochloric acid is taken. (C) In place of zinc, copper turnings are taken. (D) Sodium hydroxide is taken in place of dilute sulphuric acid and the test tube is heated.
Answer» Solution :(a)Rate of reaction will be faster as surface AREA increases. (b) No net effect will be there as both are the strong acids. (c ) No reactions will TAKE place as copper is less reactive than hydrogen. (d) Zinc can also react with NAOH to GIVE hydrogen GAS. `2NaOH+Zn to ^(Delta) Na_2ZnO_2+H_2`

Discussion

4813.	In the following reaction , xAl(OH)_3 rarr Al_2O_3 + yH_2O : x and y are
Answer» 2,3 3,4 1,2 2,2 Answer :A

Discussion

4814.	In the following reaction : x Mg + O_2 rarr 2 MgO Determine x.
Answer» 1 2 3 4 Answer :B

Discussion

4815.	In the following reaction, while reactants undergo oxidation and which reactants undergo reduction ? ZnO+C to Zn+CO
Answer» SOLUTION :`ZNO` UNDERGOES REDUCTION. C undergoes OXIDATION.

Discussion

4816.	In the following reaction the substance which is reduced is PbS+4H_(2)O_(2)toPbSO_(4)+4H_(2)O
Answer» `H_(2)O_(2)` `PBS` `H_(2)O` `PbSO_(4)` ANSWER :A

Discussion

4817.	In the following reaction : CH_4 + 2O_2 rarr CO_2 + x H_2O Determine x.
Answer» 1 3 2 4 Answer :C

Discussion

4818.	In the following pairs , identify the pair having a different (n+l) value
Answer» 4s'3p 3d,4p 4s,3d 4d,5p Answer :C

Discussion

4819.	In the following equationsNa_2CO_3 + xHCl to 2NaCl + CO_2 + H_2Othe value of x is
Answer» 1 2 3 4 Solution :`N_2CO_3 + 2HCL to 2NaCl + H_2O + CO_2 ` ` X= 2`

Discussion

4820.	In the following equation, doesthe abbreviations used represent the correct physical states of the reactants and products ? 2H_(2)(g) +O_(2)(1) to 2H_(2)O(1)
Answer» Solution :No. `O_(2) and H_(2)O`are also in the gaseous state. So, the correct FORM of the EQUATION should be `2H_(2)(g) +O_(2)(g) to 2H_(2)O(g)`

Discussion

4821.	In the following equations Na_(2) CO_(3) + x HC1 to 2NaC1 + CO_(2) + H_(2) O the value of x is
Answer» 1 2 3 4 Answer :B

Discussion

4822.	In the following chemical reaction ''zinc oxide reacts with carbon to produce zinc metal and carbon monoxide.'' ZnO+CrarrZn+CO (i) Identify the substance getting oxidised and the one getting reduced. (ii) State the reason for choosing the substances in (i) . (iii) Name the type of reaction and give another example of similar type of reaction .
Answer» Solution :(i) C is getting OXIDIZED to CO, ZNO is getting reduced to Zn . (ii) As carbon is gatting oxygen and ZnO is LOSING oxygen . (iii) It is a redox REACTION or oxidation and reduction reaction . `CuO+H_(2)rarrCu+H_(2)O`

Discussion

4823.	In the following chemical reaction, ''zinc oxide reacts with carbon to produce zinc metal and carbon monoxide.'' ZnO+C to Zn+CO (a) Identify the substance getting oxidized and the one getting reduced. (b) State the reason for choosing the substances in (a). (c) Name the type of reaction and give another example of similar type of reaction.
Answer» Solution :(a) `ZnO` is getting reduced and C is getting oxidized. (b) `ZnO` is LOSING OXYGEN and C is GAINING oxygen. (c) Redox reaction. `Fe_(2)O_(3)+3CO to 2Fe+3CO_(2),` in this reaction iron (III) oxide undergoes REDUCTION,as it is losing oxygen and `CO` gents oxidized as it is gaining oxygen.

Discussion

4824.	In the extration of iron, the most preferred ores are
Answer» HEMATITE and limonite COPPER PYRITES and siderite magnetite and IRON pyrites limonite and copper pyrites Answer :A

Discussion

4825.	In the extraction of aluminium from bauxite ______ is added to lower the melting point of bauxite.
Answer» ANSWER :CRYOLITE

Discussion

4826.	In the equation NaOH + HNO_3toNaNO_3 +H_2Onitric acid is acting as
Answer» an OXIDISING agent an acid a NITRATING agent a DEHYDRATING agent Solution :a nitrating agent

Discussion

4827.	In the environment, materials causing biomagnification
Answer» get recycled quickly decompose only in soil remain as PERMANENT residues are STORED in less amount in trophic levels Solution : remain as permanent residues

Discussion

4828.	In the eletroplating of an objectwith silver , _______ is selected as electrolyte .
Answer» SOLUTION :SODIUM argentocyanide

Discussion

4829.	In the electroplating of iron by nickel, nickel sulphate solution is taken as an electrolyte. What is the acid that is added to the electrolyte during the process ?
Answer» HCl HCN `HNO_(3)` `H_(2)SO_(4)` Answer :D

Discussion

4830.	In the electron-dot structure, the valence-shell electrons are represented by crosses or dots. (a) The atomic number of chlorine is 17. Write its electronic configuration . (b) Draw the electron-dot structure of a chlorine molecule.
Answer» Solution :a] Chlorine: CL [17] - ELECTRONIC CONFIGURATION is 2,8,7. b] `:underset(ddot)OVERSET(ddot)(Cl):underset(ddot)overset(ddot)(Cl)` Chlorine molecule.

Discussion

4831.	In the electrolytic refining of copper , copper is
Answer» DEPOSITED at the ANODE deposited at the cathode deposited below the cathode as cathode mud left behind in solution as copper ions ANSWER :B

Discussion

4832.	In the electrolytic refining of a metal M, What would you take as an anode, the cathode and the electrolyte?
Answer» Solution : In the electrolytic refining, IMPURE metal (M) is TAKEN as an ANODE and THIN strip of pure metal (M) is taken as a CATHODE and solution of soluble salt of metal (M) is taken as an electrolyte.

Discussion

4833.	In the electrolytic refining a metal M, what would you take as the anode, the cathode and the electrolyte ?
Answer» SOLUTION :During the ELECTROREFINING of metal, the impure metal is made as anode, a THIN STRIP of pure metal M is made as CATHODE. The electrolyte used a soluble salt of metal M, to be refined.

Discussion

4834.	In the electrolytic reduction of alumina, the electrolyte is covered with coke powder because it
Answer» PREVENTS oxidation of aluminium formed REACTS with aluminium forming aluminium carbide prevents heat LOSS from the ELECTROLYTE NONE of the above Answer :C

Discussion

4835.	In the electrolyte refining of a meal M, what would take the anode, the cathode and the electrolyte ?
Answer» Solution :Anode `rarr` IMPURE metal Cathode `rarr` PURE metal Electrolyte `rarr` Metal.s salt solution

Discussion

4836.	In the electrolysis refining of blister copper , a thin strip of pure copper is used as _______.
Answer» SOLUTION :CATHODE

Discussion

4837.	In the electrolysis of water : Why are few drops of dil. H_(2)SO_(4) added to the water ?
Answer» Solution :PURE water does not conduct electricity. A few drops of DIL . `H_(2)SO_(4)` are added to make water CONDUCTING.

Discussion

4838.	In the electrolysis of water : Why is the volume of gas collected at one electrode is double of the other ?
Answer» SOLUTION :`H:O=2:1`

Discussion

4839.	In the electrolysis of water : Name the gas collected at the cathode and the anode.
Answer» SOLUTION :The FOLLOWING GASES are collected : At Cathode : Hydrogen At Anode : Oxygen

Discussion

4840.	In the electrolysis of water: (i) Name the gas collected at the cathode and anode respectively . (ii) Why is the volume of one gas collected at oneelectrode is double than that at the other ? Name this gas . (iii) How will you test the evolved gases?
Answer» Solution :(i) At Cathode : hydrogen gas `(H_(2))` At Anode: oxygen gas `(O_(2))` (II) Since, `2H_(2)O overset ("Electric current ")rarr 2H_(2)+O_(2)` 2 MOLECULES of `H_(2)O`, so the volume of `H_(2)` liberated is double that of `O_(2)` (iii) When a burning SPLINTER is brought near the mouth of the liberated gases, the burning splinter extinguishes near the `H_(2)` gas while the burning splinter keeps burning more near the `O_(2)` gas.

Discussion

4841.	In the electrochemical series, ions are arranged in an increasing order of discharge potentials
Answer» ANSWER :TRUE

Discussion

4842.	In the double displacement reaction between aqueous potassium iodide and aqueous lead nitrate, a yellow precipitate of lead iodide is formed. While performing the activity if lead nitrate is not available, which of the following can be used in place of lead nitrate?
Answer» LEAD sulphate (INSOLUBLE) Lead acetate Ammonium NITRATE POTASSIUM sulphate Answer :B

Discussion

4843.	In the double displacement reaction aqueous potassium iodide and aqueous lead nitrate, a yellow precipitate of lead iodide is formed. While performing th activity if lead nitrate is not available, which of the following can be used in place of lead nitrate ?
Answer» Lead sulphute (insoluble) Lead acetate Ammonium nitrate POTASSIUM sulphate SOLUTION :Lead sulphate being insoluble will not dissociate to GIVE lead ions. Hence PRECIPITATION of lead iodide will not be POSSIBLE with lead sulphate.

Discussion

4844.	In the decomposition , 2N_(2)O_(5) hArr 4NO_(2) + O_(2) oxygen gas is produced at the average rate of 9.1 xx 10^(-4) mol L^(-1) s^(-1) . Over the same period what is the average rate of production of NO_(2) and loss of N_(2)O_(5)
Answer» Solution :(i) Rate of reactionrespective to each REACTANT and product (ii) EQUATING RATES of reactions with each other on the basis of stoichiometric coefficients (iii) `3.6xx10^(-3)` mol K`L^(-1) s^(-1), 1.8xx10^(-3)` mol `L^(-1) s^(-1)`.

Discussion

4845.	In the d-block elements as we move along a period the atomic radius decreases in the beginning, reaches minimum and then increases towards the end of the series. Explain with appropriate reasons.
Answer» Solution :In a particular series of d-block elements, electron filling TAKES place in the penultimate shell. HENCE their atomic size decreascs up to the `7^(th)` group and reaches minimum and then again increases because with the pairing of electrons, repulsive FORCE also increases. The repulsion among the added electrons exceeds the increased force of attraction (due to the increase of nuclear charge) after the `8^(th)` group. Hence, atomic radius increases slightly.

Discussion

4846.	In the chemical equation, 2Mg + O_2to2MgO, O_2represents
Answer» ATOMS of OXYGEN joined together in a MOLECULE molecules of oxygen grams of oxygen moles of oxygen Solution :atoms of oxygen joined together in a molecule

Discussion

4847.	In the brass alloy , which is solvent ?
Answer» Zn Co AG Cu Answer :D

Discussion

4848.	In the blast furnace/the flux is
Answer» ACIDIC BASIC AMPHOTERIC not matter Answer :B

Discussion

4849.	In the alumino thermic process the role of Al is ……….
Answer» OXIDIZING AGENT REDUCING agent hydrogenating agent sulphurising agent ANSWER :B

Discussion

4850.	In test-tubes Aand B , zinc sulphate solution and silver nitrate solution are taken respectively .Copper trunings are added to both test-tubes . In which of the two test-tubes do you observe the reaction. Justify your answer with scientific reason.
Answer» SOLUTION :Test-tube B CONTAINING SILVER NITRATE solution .Because silver from silver nitrate solution.

Discussion

Explore topic-wise InterviewSolutions in .

In the long form of periodic table the total number of groups are

In the hydrocarbon HC -= C -H,the covalency of carbon is

In the Hall's process , cathode used is ………… .

In the given figure of Cotyledon the parts labelled as A and B respectively are

In the formation of the compound XY, atoms of X lost one electrons each while atoms of Y gained one electron each. What is the nature of bond in XY? Predict the two properties of XY.

In the formation of nitrogen molecule.

In the following reaction , xAl(OH)_3 rarr Al_2O_3 + yH_2O : x and y are

In the following reaction : x Mg + O_2 rarr 2 MgO Determine x.

In the following reaction, while reactants undergo oxidation and which reactants undergo reduction ? ZnO+C to Zn+CO

In the following reaction the substance which is reduced is PbS+4H_(2)O_(2)toPbSO_(4)+4H_(2)O

In the following reaction : CH_4 + 2O_2 rarr CO_2 + x H_2O Determine x.

In the following pairs , identify the pair having a different (n+l) value

In the following equationsNa_2CO_3 + xHCl to 2NaCl + CO_2 + H_2Othe value of x is

In the following equation, doesthe abbreviations used represent the correct physical states of the reactants and products ? 2H_(2)(g) +O_(2)(1) to 2H_(2)O(1)

In the following equations Na_(2) CO_(3) + x HC1 to 2NaC1 + CO_(2) + H_(2) O the value of x is

In the extration of iron, the most preferred ores are

In the extraction of aluminium from bauxite ______ is added to lower the melting point of bauxite.

In the equation NaOH + HNO_3toNaNO_3 +H_2Onitric acid is acting as

In the environment, materials causing biomagnification

In the eletroplating of an objectwith silver , _______ is selected as electrolyte .

In the electroplating of iron by nickel, nickel sulphate solution is taken as an electrolyte. What is the acid that is added to the electrolyte during the process ?

In the electron-dot structure, the valence-shell electrons are represented by crosses or dots. (a) The atomic number of chlorine is 17. Write its electronic configuration . (b) Draw the electron-dot structure of a chlorine molecule.

In the electrolytic refining of copper , copper is

In the electrolytic refining of a metal M, What would you take as an anode, the cathode and the electrolyte?

In the electrolytic refining a metal M, what would you take as the anode, the cathode and the electrolyte ?

In the electrolytic reduction of alumina, the electrolyte is covered with coke powder because it

In the electrolyte refining of a meal M, what would take the anode, the cathode and the electrolyte ?

In the electrolysis refining of blister copper , a thin strip of pure copper is used as _______.

In the electrolysis of water : Why are few drops of dil. H_(2)SO_(4) added to the water ?

In the electrolysis of water : Why is the volume of gas collected at one electrode is double of the other ?

In the electrolysis of water : Name the gas collected at the cathode and the anode.

In the electrolysis of water: (i) Name the gas collected at the cathode and anode respectively . (ii) Why is the volume of one gas collected at oneelectrode is double than that at the other ? Name this gas . (iii) How will you test the evolved gases?

In the electrochemical series, ions are arranged in an increasing order of discharge potentials

In the double displacement reaction between aqueous potassium iodide and aqueous lead nitrate, a yellow precipitate of lead iodide is formed. While performing the activity if lead nitrate is not available, which of the following can be used in place of lead nitrate?

In the double displacement reaction aqueous potassium iodide and aqueous lead nitrate, a yellow precipitate of lead iodide is formed. While performing th activity if lead nitrate is not available, which of the following can be used in place of lead nitrate ?

In the decomposition , 2N_(2)O_(5) hArr 4NO_(2) + O_(2) oxygen gas is produced at the average rate of 9.1 xx 10^(-4) mol L^(-1) s^(-1) . Over the same period what is the average rate of production of NO_(2) and loss of N_(2)O_(5)

In the d-block elements as we move along a period the atomic radius decreases in the beginning, reaches minimum and then increases towards the end of the series. Explain with appropriate reasons.

In the chemical equation, 2Mg + O_2to2MgO, O_2represents

In the brass alloy , which is solvent ?

In the blast furnace/the flux is

In the alumino thermic process the role of Al is ……….

In test-tubes Aand B , zinc sulphate solution and silver nitrate solution are taken respectively .Copper trunings are added to both test-tubes . In which of the two test-tubes do you observe the reaction. Justify your answer with scientific reason.