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InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 1001. |
Which of the following has the largest number of particles? |
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Answer» `"8 g of "CH_(4)` `=6.023xx10^(23)" particles."` Others are less. |
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| 1002. |
Write the balanced chemical equation for thereactions : Barium chloride + Potassium sulphate to Barium sulphate + Potassium chloride |
| Answer» Solution :`underset("BARIUM chloride")(BaCl_(2)(aq))+ underset("POTASSIUM sulphate")(K_(2)SO_(4) (aq)) to underset("Barium sulphate")(BaSO_(4))+ underset("Potassium chloride")(2KCL(aq))` | |
| 1003. |
What is meant by sustainable management ? The environmentalist are insisting upon "Sustainable natural resource management" State its four advantages. |
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Answer» Solution :Sustainable management is the management of natural resources which requires a long term prespective so that it lasts for generation to come and should not be exploited for short term gains. its four advantages are : * Resources LAST for a longer duration *It PROVIDES STEADY ECONOMIC growth *It helps in ecological conservation *It reduces POLLUTION. |
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| 1004. |
When hydrogen gas is passed over heated copper (II) oxide, copper and steam are formed. Write the balanced chemical equation for this reaction and state (i) the substance oxidised and (ii) the substance reduced in the reaction. |
Answer» Solution :BALANCED equation:  (i) SUBSTANCE oxidised `=H_(2)` (II) Substance REDUCED =`CuO`. |
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| 1005. |
Which of the followingare combination reactions? 2KClO_3to2KCl+3O_2 MgO+H_2OtoMg(OH)_2 4Al+3O_2to2Al_2O_3 Zn+FeSO_4toZnSO_4+Fe |
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Answer» a and d |
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| 1006. |
Which one of the following is an example for aqueous solution? |
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Answer» Sugar in water |
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| 1007. |
Which of the statements about the reaction below are incorrect ? 2PbO(s)+C(s)to2Pb(s)+CO_(2)(g) Carbon dioxide is getting oxidised. |
| Answer» Solution :Carbon DIOXIDE is GETTING oxidised is INCORRECT ANSWER. | |
| 1008. |
Which of the following is an amphoteric oxide ? |
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Answer» calcium oxide |
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| 1009. |
Which of the following pairs can be the successive members of a homologous series? |
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Answer» `C_(3)H_(8)andC_(4)H_(10)` `C_(3)H_(8)OVERSET(+CH_(2))rarrC_(4)H_(10)` |
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| 1010. |
Vineet's father has got two more rooms constructed in their existing house. The rooms are almost complete but only the wood polish remains to be done on the doors and windows of the new room. Vineet's father had brought two litres of alcohol containing some additive which is specifically used for doingwood polish. The bottle containing this alcohol was handed over to the painters nad kept in the new room. SinceVineet's father wanted work to be finished as soon as possible, therefore, two painters were working till late at night. Before going to sleep, Vineet wanted to check how much wood polishing work the painters had done. As soon as Vineet entered one of the two new rooms, the was shocked to see that one of the painters had put some alcohol into a glas and was about to drink it. Vineet snatched the glas containing this alcohol from painter's hand before he could drink it. He then told the painter that it was not pure alcohol. Actually, it was the alcohol to which some additive had been added to make it unfit for drinking. It was to be used only for wood polish. Vineet also told the painters about the extremely harmful effects of drinking such an impure alcohol. The painter said sorry to Vineet and promised not to drink it in future. (a) What substance is most commonly added to ethyl alcohol to make it unfit for drinking? (b)Why does the addition of above substance make ethyl alcohol unfit for drinking? (c) What is alcohol called after the addition of above substance? (d) Why should alcohol be made unfit for drinking by mixing additive such as above? (e) What could have happened if the painter had consumed this particular alcohol at Vineet's house? (f) What values are displayed by Vineet this episode? |
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Answer» Solution :(a) METHYL alcohol (or methanol). (b) Methyl alcohol is a poisonous substance. So, the addition of some methyl alcohol to ethyl alcohol makes ethyl alcohol unfit for drinking. (c) Denatured alcohol. (d)A lot of alcohol is used ININDUSTRY for various purposes. So, for industrial uses, alcohol is supplied duty free (without charging production tax) by the Government. This makes the industrial alcohol much cheaper thanit market rate.so to prevent the misuse of industrial alcohol for drinking purpose (or black-marketing), it is made unfit drinking by mixing about10 per cent of a poisonous substances like methyl alcohol. (e) If the painter had consumed denatured alcohol, then the methyl alcohol presen in it could have caused severe poisoning leading to blindness and even death. (f)The values displayed by Vineet in this episode are (i) Sense of responsibility (in keeping an eye on PAINTERS working in the house )(ii) AWARENESS (that denatured alcohol is poisonous and unfit for drinking) (iii) Quick decision making (in snatching glas of denatued alcohol from the painter), and (iv) Saving his FAMILY from possible trouble (resulting from and harm to the painter). |
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| 1011. |
Whichof thefollowingcontainsmaximumnumberofmolecules ? |
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Answer» `1 GOF N_2` |
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| 1012. |
Write the balanced chemical equation for each of the following. On heating green - coloured ferrous sulphate crystals a reddish - brown solid is left and gases having a smell of burning sulphur are released. |
| Answer» SOLUTION :`2FeSO_(4)(s)overset(DELTA)(to)Fe_(2)O_(3)(s)+SO_(2)(G)+SO_(3)(g)`. | |
| 1013. |
Write the formula of the product formed when the element A (atomic number 19) combines with the element B (atomic number 17). Draw its electron-dot structure. What is the nature of the bond formed? |
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Answer» Solution :The electronic configuration of element A with atomic number 19 is 2, 8, 8, 1. It has one VALENCE electron and valency of +1. The electronic configuration of element B is 2, 8, 7. It has 7 valence ELECTRONS and valency of -1. Hence, the formula of the PRODUCT formed is AB. Its electron-dot structure is: 
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| 1014. |
What is the maxiumum number of electron , present in an orbit whose angular momentmum is (2h)/(pi) |
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Answer» 18 |
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| 1015. |
What is dichromater paper ? |
| Answer» Solution :A FILTER paper soaked in acidfied POTASSIUM dichromater solution is CALLED dichromater paper . | |
| 1016. |
What type of chemical reaction takes place when (i) limestone is heated, (ii)a magnesium ribbon is burnt in air? |
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Answer» Solution :(i)When lime stone is HEATED ,the reaction takes place is decomposition reaction. `UNDERSET("limestone")(CaCO_(3))overset(Delta)tounderset("Calcium oxide")(CaO)+underset("CARBONDIOXIDE")(CO_(2))UARR` (ii)When a magnesium ribbon is burnt in air ,it is an oxidation reaction. `underset("Magnesium")(2Mg)+O_(2)overset(Delta)tounderset("Magnesium oxide")(2MgO)` |
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| 1017. |
Which element has: a] two shells, each completely filled with electrons? b]the electron configuration 2, 8, 2? c]three shells, with four electrons in the valence shell? d] two shells, with three electrons in its valence shell? e] twice as many electrons in its second shell as in its first shell? |
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Answer» Solution :USING the fact that the PERIOD NUMBER denotes the number of shells while the number of electrons in the valence shell is given by the group number, we can find the required elements as follows: a) Last noble gas element in the `2^(nd)` period - NEON (Ne). B) `2^(nd)` group element in the 3 period - Magnesium (Mg). c] `3^(rd)` period, `14^(th)`group element - Silicon (Si). d] `2^(nd)` period, `13^(th)` group element - Boron (B). (e ) First shell can contain a maximum of 2 electrons. So, the required element should have an electronic configuration - 2,4. This would be the `2^(nd)` period, `14^(th)`group element - Carbon (C). |
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| 1018. |
Translate the following statements into chemical equations and then balance them. Hydrogen sulphide gas burns in air to give water and sulphur dioxide. |
| Answer» SOLUTION :`2H_2S(G)+3O_2(g)to2H_2O(L)+2SO_2(g)` | |
| 1019. |
Which metal exists as liquid at room temperature ? |
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Answer» MERCURY |
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| 1020. |
Write the general formula of carboxylic acids. |
| Answer» Solution :`C_n H_(2n+1) COOH`, where n = 0, 1, 2, ..... | |
| 1021. |
When Hydrogen gas is passed over heated copper (II) oxide,copper and steam are formed. Write the balanced chemical equation with physical states for this reaction. State what kind of chemical reaction is this? |
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Answer» SOLUTION :`(i) cuO(S)+H_(2)(G) overset ("Heat") RARR Cu(s) +H_(2)O(g)` (ii) Redox REACTION. |
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| 1022. |
Which of the following hydrocarbon undergo addition reactions ? C_(2)H_(6),C_(3)H_(8), C_(3)H_(6), C_(2)H_(2) and CH_(4) |
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Answer» |
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| 1023. |
The Vapour Density of a gaseous element is 5 times that of oxygen under similar conditions. It the molecules is triatomic, what will be its atomic mass? |
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Answer» Solution :`"Molecular mass of oxygen"=32u` `"DENSITY of oxygen"=(32)/(2)=16u` `"Density of gaseous element"=16xx5=80u` `"Molecular mass of gaseous element"=80xx2=160u` Atomicity of the element = 3 `"ATOMIC mass of the element"=("Molecular mass")/("Atomicity")=(160)/(3)=53.33u.` |
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| 1024. |
What is a redox reaction ? |
| Answer» SOLUTION :A CHEMICAL reaction in which oxidation and REDUCTION take PLACE simultaneously. | |
| 1025. |
Write the combustion reactions of ethane |
| Answer» SOLUTION :`C_2H_6(G) + 3.5O_2 (g)to 2CO_2(g) + 3H_2O(L) ` + HEAT | |
| 1026. |
What is meant by water of crystallisation ? How would you show that copper sulphate crystals contain water of crystallisation ? |
| Answer» Solution :Water which is present in the crystals of a COMPOUND is called water of crystallisation. It is DEFINED as the FIXED number of water MOLECULES present in one formula unit of a SALT. Copper sulphate crystals are blue in colour. On heating solid copper sulphate crystals, they lose water of crystallisation and become white. On adding a few drops of water to the white powder, blue colour of copper sulphate is restored. This shows that copper sulphate crystals contain water of crystallisation. | |
| 1027. |
Which property of metal is observed in this activity ? |
| Answer» SOLUTION :METALS can be HAMMERED into THIN SHEETS. | |
| 1028. |
You are provided with the following chemicals: [Cl_(2),H_(2)SO_(4),HCl(aq),Fe,ZnSO_(4),CO_(2),Zn,Na_(2)CO_(3),MgSO_(4),NaOHand"water"] Using suitable chemicals from the given list only, write chemical equations to prepare the following: Iron (II) sulphate |
| Answer» SOLUTION :`Fe+H_(2)SO_(4)toFeSO_(4)+H_(2)` | |
| 1029. |
You are provided with the following chemicals: [Cl_(2),H_(2)SO_(4),HCl(aq),Fe,ZnSO_(4),CO_(2),Zn,Na_(2)CO_(3),MgSO_(4),NaOHand"water"] Using suitable chemicals from the given list only, write chemical equations to prepare the following: Iron (III) chloride |
| Answer» SOLUTION :`2Fe+3Cl_(2)to2FeCl_(3)` | |
| 1030. |
You are provided with the following chemicals: [Cl_(2),H_(2)SO_(4),HCl(aq),Fe,ZnSO_(4),CO_(2),Zn,Na_(2)CO_(3),MgSO_(4),NaOHand"water"] Using suitable chemicals from the given list only, write chemical equations to prepare the following: Sodium zincate |
| Answer» SOLUTION :`Na_(2)CO_(3)+MgSO_(4)toMgCO_(3)+Na_(2)SO_(4)` | |
| 1032. |
Whan a Dobereiner triad is considered, the sum of atomic weights of extreme elements X and Z is 177.6 and difference of Z and Y is five times the number of protons present in a neon atom. Identify X, Y and Z. |
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Answer» SOLUTION :`X + y = 177xx6` `z - y = 5 xx10` `{:(177.6),(50.0),("____"),(127.6),("____"),():}` `((-)(+)-)/(x + y= 127.6)` As X, Y and Z from Dobereiner TRIED `y = (x+ z)/(2)`, where x, y and z are atomic MASSES of X, Y and Z, RESPECTIVELY `y = (177.6)/(2) = 88.8` `x = 127.6 - 88.8 = 38.8` `z = 177.6 - 38.8 = 138.8` `x = 38xx38 = 40` `X = 40 rArrCa` `Y = 88xx80 rArrSr` `Z = 138xx6 rArrBa `. |
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| 1033. |
What would be the effect on lime water, when carbon dioxide gas is passed through it ? |
| Answer» SOLUTION :LIME WATER TURNS MILKY | |
| 1034. |
What are amphoteric oxides? Give two examples of amphoteric oxides. |
| Answer» SOLUTION :Some METAL oxides show both acidic as well as basic character, such oxides are called amphoteric oxides. For EXAMPLE , (i) Aluminium oxide `(Al_2O_3)` (ii) Zinc oxide (ZNO). | |
| 1035. |
Whentwocompounds react . Iftheirionsare interchnged, thenthe reactionis called________. |
| Answer» SOLUTION :Doubledisplacement | |
| 1036. |
What is an armature? |
| Answer» SOLUTION :The SOFT IRON CORE, on which the coil is wound plus the coils is called an armature. | |
| 1037. |
What is meant by decomposition reaction ? Give examples. |
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Answer» Solution :A chemical reaction in which a single compound on heating or in presence of sunlight forms more than one products is called decomposition reaction. Examples : (1) `CaCO_(3) (s) overset("Heat")to underset("Calcium OXIDE")(CaO(s))+CO_(2)(g)` (2) `2FeSO_(4)(s) overset("Heat")to underset("Ferric oxide")(Fe_(2)O_(3)(s))+ SO_(2)(g)+SO_(3)` (3) `underset("Lead nitrate")(2Pb(NO_(3))_(2)(s)) overset("Heat")to underset("Lead oxide")(2PbO(s))+4NO_(2)(g)+SO_(3)` |
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| 1038. |
Write the effect of dilute hydrochloric acid on the colour of the following indicators: Methyl orange |
| Answer» SOLUTION :It will CHANGE to RED COLOUR | |
| 1039. |
Write the type of chemical reaction in the following. reaction between acid and base |
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Answer» SOLUTION :Neutralisatior REACTION Oxidation reaction |
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| 1040. |
When does the breaking and forming of bonds of chemical substances take place ? |
| Answer» SOLUTION : In CHEMICAL REACTION | |
| 1041. |
Which gas is usually liberated when an acid reacts with a metal ? Illustrate with an example . How will you test the presence of this gas ? |
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Answer» Solution :When a metal reacts with an acid , usually hydrogen gas is liberated . For example , zinc reacts with dilute sulphuric acid as follows : `UNDERSET("Zinc")(ZN)+underset("Sulphuric acid")(H_2SO_4)rarrunderset("Zinc sulphate")(ZnSO_4)+underset("Hydrogen")(H_2)` The hydrogen evolved can be TESTED by passing the gas through SOAP solution and then bringing a burningcandle near the soap bubble filled with the gas. The soap bubble BURSTS and the hydrogen gas burns with a pop sound. |
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| 1042. |
What happens when : (i) Dilute hydrochloric acid is added to solidsodium carbonate. Quicklime is treated withwater . (iii) Sodium chloride solution is added to lead nitrate solution . Also write the chemical equation ineach case. |
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Answer» Solution :(i) `Na_(2)CO_(3)(S)+2HCl(aq)rarr2NaCl(aq)+H_(2)O(l)+CO_(2)(G)` (ii) `CaO(S)+H_(2)O(l)rarrCa(OH)_(2)(aq)+"Heat"` (iii) `Pb(NO_(3))_(2)(aq)+NaCl(aq)rarrPbCl_(2)(s)+(2NaCl(aq)` |
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| 1043. |
What are the merits and demerits of Newland 's classification? |
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Answer» Solution :Merits (a) This classification worked well for lighter elements only up to Ca. (b) This classification GAVE us a relation between the properties of elements and their atomic MASSES. (c) It was shown by this· classification for the first time. that there exists a periodicity in the propetties of the elements. Demerits : (a) This classification failed when the heavier elements beyond Ca were arranged ACCORDING to Newlands law of octaves (b) At the time ofthis law, noble gases were unknown. When noble gases, were discovered, neon (NE) was placed between F and Na and argon (Ar) between Cl and K. so these became the ninth elements and not the eighth. which had SIMILAR properties. |
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| 1044. |
Which of the following organic compound is used as a fuel? |
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Answer» `HCOOH` |
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| 1045. |
What is the special feature of the structure of ethyne? |
| Answer» SOLUTION :TRIPLE BOND between C ATOMS, `H-C -=C-H` | |
| 1046. |
The use of natural reasorces should be |
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Answer» PROFITABLE |
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| 1047. |
What is a neutralization reaction ? Give two examples. |
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Answer» SOLUTION :Reaction of an acid with a base is called neutralization reaction. Example : (a) When HYDROCHLORIC acid REACTS with sodium hydroxide (base), it produces sodium CHLORIDE and water because of neutralization reaction. `2HCl + 2NaOH rarr 2NaCl + 2H_(2)O` (b) When sulphuric acid reacts with sodium hydroxide, sodium sulphate and water are formed after neutralization reaction. `2NaOH + H_(2)SO_(4) rarr Na_(2)SO_(4) + 2H_(2)O` |
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| 1048. |
Write the name of chemical used in black and white photography. |
| Answer» SOLUTION :SILVER BROMIDE | |
| 1049. |
What is fertilization? Distinguish between external fertilisation and internal fertilisation. |
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Answer» Solution :FERTILISATION is defined as the fusion of a MALE gamete (Sperm) with a female gamete (an ovum or egg) to form a ZYGOTE during sexual reproduction. External fertilisation : The fusion of male gamete (sperm) and female gamete (ovum) occur outside the body. Both individuals discharge their gametes outside the body. DEVELOPMENT occurs outside the body. Ex : frog. Internal fertilisation : The fusion of gamates occurs inside the body Only the male discharge sperm into female genital tract. Development occurs inside the body. Ex: Humans, cattle ETC. |
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| 1050. |
Write the structural formula of chloroethane |
| Answer» SOLUTION :`CH_(3)CH_(2)CL`or`H-UNDERSET(H) underset(|) overset(H) overset(|)C-underset(H) underset(|) overset(H) overset(|)C-Cl` | |