8881 + Interview Questions in Chemistry in Class 10 Page 7 InterviewSolution

301.	Which element has two shells, both of which are completely filled with electrons?
Answer» SOLUTION : NE (2,8)

Discussion

302.	Write the name and formula of second member of the carbon compounds having functional group - OH.
Answer» SOLUTION :The SECOND member is ETHANOL . Its MOLECULAR formula is `CH_3CH_2OH(C_2H_5OH)`.

Discussion

303.	What is balanced chemicalreaction ?
Answer» SOLUTION :A balancedchemicalequationis thesimplifiedreprestationof achemicalreactionwhichdescribesthechemicalcomposition, physicalstateof thereactantsand the PRODUCTS, andthereactionconditions.

Discussion

304.	Which metals are mixed with iron to get stainless steel?
Answer» SOLUTION :NICKEL and CHROMIUM

Discussion

305.	Which property of Mn of the alloy spiegel is exploited in the manufacture of steel?
Answer» Solution :(i) Reactivity of Mn with the IMPURITIES. (ii) Kinds of impurities PRESENT in iron obtained from the blast furance. (III) Chemical behaviour of manganese. (iv) Affinity of manganese TOWARDS certain impurities. (V) Formation of slag. (vi) Tpye of bond that can be formed between iron and manganese. (vii) Effect of the formation of the above bonds on the property of steel.

Discussion

306.	What happens when carbon dioxide and water react in the same ratio ?
Answer» Solution :When six molecule carbon dioxide and six MOLECULES of water undergo REACTION, it FORMS glucose with EVOLUTION oxygen gas. `6CO_(2) + 6H_(2)O to underset("Glucose")(C_(6)H_(12)O_(6)) + 6O_(2)`

Discussion

307.	Which one is more active , potassium or aluminium ?
Answer» SOLUTION :POTASSIUM

Discussion

308.	Which of the following metal shows variable valency ?
Answer» LEAD POTASSIUM CALCIUM ALUMINIUM ANSWER :A

Discussion

309.	Which of the following gases can be used for storage of fresh sample of a oil for a long time ?
Answer» Carbon DIOXID or OXYGEN Nitrogen or oxygen Carbon dioxide or helium Helium or nitrogen Solution :Carbon dioxide and oxygen might REACT with the oil. Helium and nitrogen gases do not react.

Discussion

310.	what will happen when solution of sodium hydroxide is added to solution of sodium carbonate ?
Answer» SOLUTION :No REACTION will OCCUR.

Discussion

311.	What are the methods used to prevent corrosion?
Answer» Solution : Corrosion of metals is prevented (i) by COATING with paints(II) by coating with oil and grease (III) by alloying with other metals (iv) by the process of galvanization (v) by ELECTROPLATING (vi) by sacrificial protection

Discussion

312.	What is meant by rancidity ? State any two methods to prevent it.
Answer» Solution :Rancidity is the slow process where the oils and fats PRESENT in food are oxidized when exposed to oxygen, leading to foul smell and a bad TASTE. Different METHODS USED to prevent rancidity are : (a) Adding chemical called ANTIOXIDANTS, which prevent or slow down the oxidation process. (b) Storing foods in airtight containers or in a refrigerator.

Discussion

313.	Which of the following salts can produce only two types of radicals ?
Answer» `NaKCO_(3)` `CaOCl_(2)` `NH_(4)HSO_(4)` `NA(NH_(4))HPO_(4)` Solution :`NaKCO_(3) rarr Na^(+) + K^(+) + CO_(3)^(-2)` `CaOCl_(2) rarr Ca^(+2) + Ocl^(-1) + Cl^(-)` `underset("(two type of RADICALS)")(NH_(4)HSO_(4) rarr NH_(4)^(+)) + HSO_(4)^(-)` `Na(NH_(4)) HPO_(4) rarr Na^(+) + NH_(4)^(+) + HPO_(4)^(-)`

Discussion

314.	Write the equations of chemical reactions
Answer» SOLUTION :`2MG(s) + O_2(g) to2MgO(s)` `MgO(s) + H_2O(l)to Mg(OH)_2 (AQ)` `S(s) + O_2(g) to SO_2(g)` `SO_2(g) + H_2O (l) to H_2SO_3(aq)`

Discussion

315.	While constructing a house ,a builder selects marble flooring and marble table tops for the kitchen where vinegar and juice of lemon, tamarind etc. Are more often used for cooking. Will you agree to this selection and why?
Answer» Solution :No the substance like VINEGAR, TAMARIND etc. contain ACIDS which when accidentally fall on marble will react with the marble causing discolouration.

Discussion

316.	The rocky impurities associated with the ore.
Answer» SOLUTION :GANGUE.

Discussion

317.	Two ores A and B were taken. On heating ore A gives CO_2 whereas, ore B gives SO_2. What steps will you take to convert them into metals?
Answer» SOLUTION :SINCE ore A gives `CO_2` and ore B gives `SO_2`. THEREFORE, ORES are `MCO_3 and MS`. As A is a carbonate ore, it is first subjected to calcination followed by reduction. `MCO_3to^(Calci nation) MO+CO_2` `MO+C to^(Reduction )M+CO` As B is a sulphide ore, it is first subjected to ROASTING followed by reduction. `2MS+3O_2 to^(Roas ti ng)2MO+2SO_2` `MO+C to^(Reduction )M+CO`

Discussion

318.	The structure of two organic compounds are given below: i) CH_3-CH_2-CH_2-CH_2-OH ii) CH_3-CH_2-O-CH_2-CH_3 Which type of isomerism do they exhibit?
Answer» ANSWER :FUNCTIONAL GROUP ISOMERISM

Discussion

319.	Which of the following is not an "element+element to compound" type reaction?
Answer» `C_(s)+O_(2(G))toCO_(2(g))` `2K_((s))+Br_(2(l))to2KBr_((s))` `2CO_((g))+O_(2(g))to2CO_(2(g))` `4Fe_(s)+3O_(2(g))to2Fe_(2)O_(3(s))` Solution :It involves ONE reactant compound i.e., carbon monoxide (CO). `underset("compound")(2CO_((g)))+underset("ELEMENT")(O_(2(g)))tounderset("Compound")(2CO_(2))`

Discussion

320.	Write two harmful effects of using plastic bags on the environment. Suggest alternatives to the usage of plastic bags.
Answer» Solution :Two harmful effects of using plastic BAGS on the ENVIRONMENT are : (i) Since plastic bags are non-biodegradable so they REMAIN in soil for a very long time making it unsuitable for vegetation. (ii) On burning, they release very toxic chemicals in the AIR. (III) Sometimes animals ingest these and may choke to death e.g., cows, fishes etc. Other alternatives for plastic bags can be cloth bags, jute bags or canvas bags.

Discussion

321.	What happens when ethanol is warmed with ethanoic acid in thr presence of few drops of concentrated sulphuric acid ? Give equation of the reaction and the name of the product formed.
Answer» Solution :When ETHANOL REACTS with ethanoic acid on warming with conc. `H_(2)SO_(4)`, sweet smelling ESTER is formed. `CH_(3)COOH + C_(2)H_(5)OH rarr UNDERSET("Ester")(CH_(3)COOC_(2)H_(5))+H_(2)O` The name of the product is ethyl ethanoate.

Discussion

322.	Write the relationship between (i) Atomicity and Molecular mass (ii) Molecular mass and Vapour density.
Answer» Solution :(i) `"Atomicity"=("Molecular MASS")/("ATOMIC mass")` (ii) `"Molecular mass"=2XX"VAPOUR density"`

Discussion

323.	What is the name of the carboxylic acid which is extracted from ants?
Answer» SOLUTION :FORMIC ACID (methanoic acid)

Discussion

324.	Thestandard Temperatureelementis _________.
Answer» SOLUTION :`273.15 K`

Discussion

325.	Two black female mice are crossed with a brown male. Later female I produces 9 black and 7 brown offsprings, female II produced 57 black off springs during first filial generation. Then i) What inference can you make concerning inheritance of black and brown coloured mice? ii) With the help of phenotype given, find out what are the genotypes of parents?
Answer» Solution : i) Inference regarding the INHERITANCE of black and brown COLOUR. Since the black colour genes are dominant over brown .colour genes, only black coloured offsprings appear in the first filial generation. (in case of female 2). ii) Since both black and brown offsprings are obtained when female 1 is crossed with a brown MALE (BB), its genotype would be Bb (heterozygous). Female 2 will have genotype BB (homozygous).

Discussion

326.	Which element has a total of two shells, with three electrons in its valence shell?
Answer» SOLUTION :B (2,3)

Discussion

327.	Which among the following does not undergo hydrolysis ?
Answer» `Na_(2)CO_(3)` `CH_(3)COOH` `CH_(3)COONH_(4)` `K_(2)SO_(4)` Answer :D

Discussion

328.	Which of the following pairs will give displacement reactions? NaCl solution and copper metal (b)MgCl_2 solution and aluminium metal (c ) MgCl_2 solution and aluminium metal (d)AgNO_3 solution and copper metal
Answer» SOLUTION :No displacement reaction will occur between NaCl solution and copper metal, as copper metal is LESS REACTIVE than sodium metal. (b) AL is less reactive than Mg. So, no displacement reaction will take place. (c )Ag is less reactive than FE So, no displacement reaction will take place. (D) Cu(Copper metal) is more reactive than silver (Ag), so the displacement reaction will take place between `AgNO_3` solution and copper metal.

Discussion

329.	Which amongst the following are called Magic numbers ?
Answer» 2,8,8,18 2,8,8,32 2,8,18,32 None of these Answer :C

Discussion

330.	What do you mean by valency?
Answer» SOLUTION :The combining CAPACITY of an ELEMENT is called the VALENCY of that element.

Discussion

331.	When we say the resistors are in parallel ? Write the expression for the resistors in parallel. How many 176 Omega resistors (in parallel) are required to carry on a 220V line ?
Answer» Solution :We can say that resistors are in parallel if same potential difference is APPLIED across them. For three resistors if we connect them in parallel the equivalent resistance is R `(1)/(R) = (1)/(R_(1))+ (1)/(R_(2))+ (1)/(R_(3))` For x number of resistors of resistance 176 the equivalent resistance of the resistors connected in parallel is GIVEN by ohm.s law as V= IR `R+(V)/(I)` Where ,supply voltage, V=220V current I=5A Equivalent resistance of the combination -R given as `(1)/(R) =x xx (1)/(176)` `R= (176)/(x)` `x= (176 xx I)/(V)= (176 xx 5)/(220)` x= 4

Discussion

332.	Which of the following compounds contain a carobxyl group : CH_(3)OH, CH_(3)CHO, CH_(3)COOH, CH_(3)COCH_(3).
Answer» SOLUTION :`CH_(3)COOH`.

Discussion

333.	Who developed the long form of periodic table ?
Answer» NEILS Bohr Mosley Mendeleev Lothar Meyer Answer :B

Discussion

334.	(i)What is the chemical nameand chemical formula of Plaster of paris? (ii) Write a reaction between plaster of paris and water. (iii) Write two uses of washing soda. (iv) What is chlor alkali process? Name two products obtained during this process.
Answer» Solution :(i) Chemical name of Plaster of paris is calcium sulphate hemihydrate. Chemical formula of plaster of paris = `CaSO_4. 1/2 H_2O`. (ii) When it mixed with WATER, crystals of gypsum are produced and set into hard mass. `CaSO_4. 1/2 H_2O+3/2 H_2O to CaSO_4. 2H_2O` Plaster of paris Gypsum (iii) Uses of washing soda: (a) IT is used in softening of hard water. (b) It is used as cleaning AGENT for domestic purposes. (iv) Caustic soda (NaOH) is OBTAINED by the electrolysis of aqueous solution of sodium chloride (called BRINE) and the process is called chlor alkali. Products obtained during this process are chlorine and hydrogen. `2NaCl(aq)+2H_2O(l)to^(El ectric current) 2NaOH(aq)+Cl_2(g)+H_2(g)` (at cathode) (at anode) (at anode)

Discussion

335.	Which of the following molecules has both covalent and ionic bond
Answer» `CH_(3)Cl` `NH_(4)Cl` `HCL` `BeCl_(2)` Answer :B

Discussion

336.	Which elements has A total of two shells, with three electrons in its valence shell ?
Answer» Solution :Boron has three ELECTRONS in its VALENCE SHELL.

Discussion

337.	Which of the following is the symbol of the metal that occurs in liquid form at ordinary temperature?
Answer» Na Sn Pb Hg Solution : MERCURY (Hg) is an element that occurs in LIQUID form at ordinary TEMPERATURE, Na, Sn and Pb all THREE are SOLIDS.

Discussion

338.	What do you understand by periods in the Periodic Table?
Answer» Solution :The horizontal rows in the LONG form of the PERIODIC Table are CALLED periods.

Discussion

339.	Write the chemical name of the coating that forms on silver and copper articles when these are left exposed to moist air.
Answer» SOLUTION :Silver SULPHIDE, copper carbonate coating is FORMED on AG & Cu ARTICLE.

Discussion

340.	Write the next homologue of each of the following : (i) C_(2)H_(4), (ii) C_(4)H_(6)
Answer» ANSWER :(i) `C_(6)H_(6)`, (II) `C_(5)H_(8)`

Discussion

341.	Which among the following is not an anomalous pair in Mendeleev's periodic table?
Answer» (a) `Co, NI` (B) `Te, I ` (c) `Ar, K` (d) `Sc, Ga` Solution :In case of first three pairs, the ATOMIC weights of LATTER elements are greater than the FORMER elements, so, they are called anomalous pairs. The last pair is not an anomalous pair.

Discussion

342.	What property do all elements in the same column of the Periodic Table as fluorine have in common?
Answer» SOLUTION :VALENCY EQUAL to 1

Discussion

343.	What are thermal decomposition reactions?
Answer» Solution :In thermal decomposition reaction ,the reactant is decomposed by APPLYING heat. For EXAMPLE ,on HEATING mercury (II)oxide is decomposed into mercury and oxygen gas.`2HgO_((s))overset(DELTA)to2Hh_((l))+O_(2(g))`

Discussion

344.	Write the equations for the reaction of ethyne with bromine
Answer» SOLUTION :`CH -= CH overest(Br_2) (to) BRHC = CHBR OVERSET(Br_2) Br_2HC - CHBr_2`

Discussion

345.	When the gases sulphur dioxide and hydrogen sulphide mix in the presence of water, the reaction SO_(2) + 2H_(2) S to 2H_(2) O + 3S Here hydrogen sulphide is acting as
Answer» an OXIDISING agent a REDUCING agent a DEHYDRATING agent a catalyst Answer :B

Discussion

346.	The chemical formula of soda ash is
Answer» SOLUTION :Anhydrous SODIUM carbonate ` (Na_(2)CO_(3))`

Discussion

347.	Zinc can displace copper from copper sulphate solution bacause zine is
Answer» more REACTION than copper less REACTIVE than copper more STABLE than copper less stable than copper Answer :A

Discussion

348.	What are the difference between atoms and molecules?
Answer» SOLUTION :

Discussion

349.	Which gas is evolved when a piece of a sodium is a added to ethanol ? Write the equation for the reaction involved.
Answer» SOLUTION :The gas evolved is the HYDROGEN gas. `UNDERSET(" ethanol")(2C_(2)H_(5)OH) + underset("sodium")(2Na) to underset(" Sodium ETHOXIDE")(2C_(2)H_(5)Ona) + underset(" hydrogen")H_(2)`

Discussion

350.	What happens when chlorine is passed over slacked lime at 313k? Write chemical equation of the reaction involved and state two uses of the product obtained.
Answer» Solution :BLEACHING powder is formed. `Ca(OH)_(2)+Cl_(2)overset(313K)toCaOCl_(2)+H_(2)O` i) It is USED as bleaching agent in paper and textile INDUSTRIES. ii) It is used as disinfectant in purification of drinking water.

Discussion

Explore topic-wise InterviewSolutions in .

Which element has two shells, both of which are completely filled with electrons?

Write the name and formula of second member of the carbon compounds having functional group - OH.

What is balanced chemicalreaction ?

Which metals are mixed with iron to get stainless steel?

Which property of Mn of the alloy spiegel is exploited in the manufacture of steel?

What happens when carbon dioxide and water react in the same ratio ?

Which one is more active , potassium or aluminium ?

Which of the following metal shows variable valency ?

Which of the following gases can be used for storage of fresh sample of a oil for a long time ?

what will happen when solution of sodium hydroxide is added to solution of sodium carbonate ?

What are the methods used to prevent corrosion?

What is meant by rancidity ? State any two methods to prevent it.

Which of the following salts can produce only two types of radicals ?

Write the equations of chemical reactions

While constructing a house ,a builder selects marble flooring and marble table tops for the kitchen where vinegar and juice of lemon, tamarind etc. Are more often used for cooking. Will you agree to this selection and why?

The rocky impurities associated with the ore.

Two ores A and B were taken. On heating ore A gives CO_2 whereas, ore B gives SO_2. What steps will you take to convert them into metals?

The structure of two organic compounds are given below: i) CH_3-CH_2-CH_2-CH_2-OH ii) CH_3-CH_2-O-CH_2-CH_3 Which type of isomerism do they exhibit?

Which of the following is not an "element+element to compound" type reaction?

Write two harmful effects of using plastic bags on the environment. Suggest alternatives to the usage of plastic bags.

What happens when ethanol is warmed with ethanoic acid in thr presence of few drops of concentrated sulphuric acid ? Give equation of the reaction and the name of the product formed.

Write the relationship between (i) Atomicity and Molecular mass (ii) Molecular mass and Vapour density.

What is the name of the carboxylic acid which is extracted from ants?

Thestandard Temperatureelementis _________.

Which element has a total of two shells, with three electrons in its valence shell?

Which among the following does not undergo hydrolysis ?

Which of the following pairs will give displacement reactions? NaCl solution and copper metal (b)MgCl_2 solution and aluminium metal (c ) MgCl_2 solution and aluminium metal (d)AgNO_3 solution and copper metal

Which amongst the following are called Magic numbers ?

What do you mean by valency?

When we say the resistors are in parallel ? Write the expression for the resistors in parallel. How many 176 Omega resistors (in parallel) are required to carry on a 220V line ?

Which of the following compounds contain a carobxyl group : CH_(3)OH, CH_(3)CHO, CH_(3)COOH, CH_(3)COCH_(3).

Who developed the long form of periodic table ?

(i)What is the chemical nameand chemical formula of Plaster of paris? (ii) Write a reaction between plaster of paris and water. (iii) Write two uses of washing soda. (iv) What is chlor alkali process? Name two products obtained during this process.

Which of the following molecules has both covalent and ionic bond

Which elements has A total of two shells, with three electrons in its valence shell ?

Which of the following is the symbol of the metal that occurs in liquid form at ordinary temperature?

What do you understand by periods in the Periodic Table?

Write the chemical name of the coating that forms on silver and copper articles when these are left exposed to moist air.

Write the next homologue of each of the following : (i) C_(2)H_(4), (ii) C_(4)H_(6)

Which among the following is not an anomalous pair in Mendeleev's periodic table?

What property do all elements in the same column of the Periodic Table as fluorine have in common?

What are thermal decomposition reactions?

Write the equations for the reaction of ethyne with bromine

When the gases sulphur dioxide and hydrogen sulphide mix in the presence of water, the reaction SO_(2) + 2H_(2) S to 2H_(2) O + 3S Here hydrogen sulphide is acting as

The chemical formula of soda ash is

Zinc can displace copper from copper sulphate solution bacause zine is

What are the difference between atoms and molecules?

Which gas is evolved when a piece of a sodium is a added to ethanol ? Write the equation for the reaction involved.

What happens when chlorine is passed over slacked lime at 313k? Write chemical equation of the reaction involved and state two uses of the product obtained.