

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.
1101. |
A sample of water containing some dissolved table sugar and common salt is passed through organic ion exchange resins. The resulting water will beA. TastelessB. SweetC. SaltyD. None of these |
Answer» Correct Answer - B A sample of water containing some dissolved table sugar and common salt is passed through organs ion exchange resins. The sesulting water will be Sweet. |
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1102. |
Which of the following reaction does not take placeA. `CuSO_(4)+ZnrarrZnSO_(4)+Cu`B. `HeCl_(2)+FerarrFeCl_(2)+Hg`C. `NaH+H_(2)OrarrNaOH+H_(2)`D. `Na_(2)SO_(3)+CO_(2)rarrNa_(2)CO_(3)+SO_(2)` |
Answer» Correct Answer - D More acidic oxide displaced less acidic oxide. |
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1103. |
One mole of magnesium nitride on reaction with an excess of water givesA. one mole of ammoniaB. one mole of nitric acidC. two moles of ammoniaD. two moles of nitric acid. |
Answer» Correct Answer - D `Mg_(3)N_(2)+3H_(2)Oto2NH_(3)+3MgO` |
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1104. |
Which gas is evolved when Mg3N2 (Magnesium nitride) is treated with H2O? Give chemical reaction. |
Answer» NH3 gas is evolved. Mg3N2 + 6H2O → 3Mg(OH)2 + 2NH3 |
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1105. |
When sodium hybride is electrolysed, hydrogen is liberated at which electrode? Give equation. |
Answer» At anode; NaH \(\overset{delectrolysis}{\longrightarrow}\) Na+ + H- at anode 2H– – 2e– → H2(g) |
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1106. |
Heavy water is used in nuclear reactors asA. Source of `alpha`- particlesB. Slowing down the speed of high energy neutronsC. Transporting heat of the reactorD. Heating purposes |
Answer» Correct Answer - B Heavy water act as moderator which can show down speed of neutrons. |
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1107. |
Why does water has a high boiling point and a high melting point as compared to H2S? |
Answer» Water molecules are associated with intermolecular H-bonding whereas H2S is not. |
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1108. |
What is the importance of heavy water with regard to nuclear power generation? |
Answer» It is used as coolant and moderator i.e., to slow down the fast moving neutrons. |
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1109. |
Which isotope of hydrogen is radioactive? |
Answer» Tritium (31H) is radioactive. |
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1110. |
Why does elemental hydrogen react with other substances slowly at room temperature? |
Answer» It is because it has high bond dissociation energy (436 kJ mol-1) |
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1111. |
Which one of the following processes will produce permanent hard water ?A. Addition of `Na_(2)SO_(4)` to waterB. Saturation of water with `CaCO_(3)`C. Saturation of water with `MgCO_(3)`D. Saturation of water with `CaSO_(4)` |
Answer» Correct Answer - D | |
1112. |
What is meant by hard water? |
Answer» Hard water is water containing bicarbonates, sulphates and chlorides of Ca2+ and Mg2+. |
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1113. |
`100 mL` of ozone at `STP` was passed through `100 mL` of `10` volume `H_(2)O_(2)` solution. What is the volume strength of `H_(2)O_(2)` after attraction?A. `9.5`B. `9.0`C. `4.75`D. `4.5` |
Answer» Correct Answer - A `O_(3)toO_(2)+O....(i)` `H_(2)O_(2)toH_(2)O+O....(ii)` `O+OtoO_(2)......(iii)` `1//2 vol ,1//2 vol ,1vol` `100 mL of O_(3)` at `STP` will produce will produce `100 mL` of `O_(2)` as such and `100 mL` of `O_(2)` after reaction with `H_(2)O_(2)`. This new volume of `100 mL` of molecular oxygen after reaction with `H_(2)O_(2)` is contributed equally by `O_(3)` and `H_(2)O_(2)`. thus `50 mL` of oxygen has been contributed by `H_(2)O_(2)`. Again, we know that Volume of `H_(2)O_(2)xx` vol stre ngth of `H_(2)O_(2)` =vol of `O_(2)` at `STP` After utilisation of `50 mL` of `O_(2)`, according to Eq. (iii), the balance `(1000-50)=950 mL` of `O_(2)` at `STP` are still retainable by `100 mL of H_(2)O_(2)`. hence vol strength of `H_(2)O_(2)` after reaction `=("Volume of " O_(2) at STP)/("Volume of "H_(2)O_(2))` `=950/100=9.5 V` `:.` volume strength `=9.5` |
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1114. |
Which of the following act as a stabiliser for the storage of `H_(2)O_(2)`?A. AlkaliB. DustC. UreaD. None of these. |
Answer» Correct Answer - C `H_(2)O_(2)` decomposes slowly on exposure to light. `2H_(2)O_(2(l))to 2H_(2)O_((l))+O_(2(g))` In the presence of metal surfaces or traces of alkali (present in glass containers), the above reaction is catalysed. It is, therefore, stored in wax-lined glass or plastic vessels in dark. Urea can be added as a stabiliser. It is kept away from dust because dus can induce explosive decomposition of the compound. |
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1115. |
Peroxodisulphate, on hydrolysis yieldsA. waterB. dihydrogenC. hydrogen peroxideD. deuterium. |
Answer» Correct Answer - C Peroxodisulphate on hydrolysis yields hydrogen peroxide. `HO_(3)SOOSO_(3)H_((aq))overset("hydrolysis")rarr 2HSO_(4(aq))^(-)+2H_((aq))^(+)+H_(2)O_(2(aq))` |
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1116. |
The temporary hardness of water due to calcium bicarbonate can be removed by addingA. `CaCO_(3)`B. `CaCI_(2)`C. HCID. `Ca(OH)_(2)` |
Answer» Correct Answer - D `Ca(HCO_(3))_(2)+Ca(OH)_(2)to underset("(Insoluble)")(2CaCO_(3))+2H_(2)O` |
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1117. |
In a permutit, the calcium and magnesium ions of hard water are exchanged byA. `CO^(2-)` and `HCO_(3)^(-)` ions of permutitB. `Na^(+)` ions of permutitC. `AI^(3+)` ions of permutitD. `Si^(4+)` ions of permutit. |
Answer» Correct Answer - B `Na_(2)Al_(2)Si_(2)O_(8). xH_(2)O+Ca^(2+)(" or " Mg^(2+))to CaAl_(2)Si_(2)O_(8). XH_(2)O+2Na^(+)` |
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1118. |
A water sample is said to contain permanent hardness if water containsA. sulphates and chlorides of calcium and magnesiumB. carbonates of calcium and magnesiumC. bicarbonates of calcium and magnesiumD. sulphates and chlorides of sodium and potassium. |
Answer» Correct Answer - A Permanent hardness of water is due to sulphates and chlorides of calcium and magnesium. |
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1119. |
Which of the following could act as a propellant for rockets?A. Liquid hydrogen + liquid nitrogenB. Liquid oxygen + liquid argonC. Liquid hydrogen + liquid oxygenD. Liquid nitrogen + liquid oxygen. |
Answer» Correct Answer - C Liquid hydrogen and liquid oxygen act as rocket propellant. |
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1120. |
Which of the following could act as a propellant for rockets ?A. `Liq. H_(2)+Liq. O_(2)`B. `Liq. N_(2)+Liq. O_(2)`C. `Liq. H_(2)+Liq. N_(2)`D. `Liq. O_(2)+Liq. Ar` |
Answer» Correct Answer - a Liq. `H_(2)` because of low atomic mass and high enthalpy of combustion and liq. `O_(2)` is strong supported for combustion. |
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1121. |
In the reaction of `F_2` and `H_2O`, water act as_____. |
Answer» Correct Answer - Reducing agent Reducing agent |
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1122. |
20mL of `H_(2)O_(2)` after acidification with dilute `H_(2)SO_(4)` required 30mL of N/12 `KMnO_(4)` for complete oxidation. Calculate the percentage of `H_(2)O_(2)` in the solution. Equivalent mass of `H_(2)O_(2)=17`. |
Answer» Correct Answer - 0.2125 `30 mL (N)/(12) KMnO_(4) -= 20 mL N_(x) H_(2)O_(2)` Normality of `H_(2)O_(2)`.soln., `Nx = (30)/(12 xx 20) = 1/8` Strength = Normality `xx` Eq. mass `= 1/8 xx 17 = 2.125 gL^(-1)` `% = (2.15)/(1000) xx 100 = 0.2125` |
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1123. |
The hardness of water due to `HCO_3` is `122pm`. Select the correct statement(s).A. The hardness of water in terms of `CaCO_(3)` is `200 p p m`B. The hardness of water in terms of `CaCO_(3)` is `100 p p m`C. The hardness of water in terms of `CaCO_(3)` is `22 p p m`D. The hardness of water in terms of `CaCO_(3)` is `95 p p m` |
Answer» Correct Answer - B::D Since `2` mol of `HCO_(3)^(ɵ)` is present, there should be one mole each of `CaCO_(3), CaCl_(2)` and `MgCl_(2)` to have equal hardness. `:. Mw of HCO_(3)^(ɵ)= 61` `p p m of HCO_(3)^(ɵ)=61xx2=122g` in `10^(6) mL H_(2)O` `[MW of CaCO_(3)=100,MW of CaCl_(2)=111, MW of MgCl_(2)=95 g mol^(-1)]` `1` mol of `CaCO_(3)=100 p p m` `1` mol of `CaCl_(2)=111 p p m` `1` mol of `MgCl_(2)=95 p p m` hence , (b) and (d) are correct option |
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1124. |
Permanent hardness is due to `CI^(ɵ)` and `SO_4^(2-)` of `Mg^(2+)` and `Ca^(2+)` and is removed by adding `Na_2CO_3`. `{:(CaSO_(4)+Na_(2)CO_(3)toCaCO_(3)+Na_(2)SO_(4)),(CaCl_(2)+Na_(2)CO_(3)toCaCO_(3)+2NaCl):}` Which of the following statements is`//`are correct?A. If hardness is `100 p p m CaCO_(3)` the amount of `Na_(2)CO_(3)` required to soften `10 L` of hard water is `10.6 g`B. If hardness is `100 p p m CaCO_(3)`, the amount of `Na_(2)CO_(3)` required to soften `10L` of hard water is `1.06 g`.C. If hardness is `420 p p m MgCO_(3)`, the amount of `Na_(2)CO_(3)`required to soften `10 L` of hard water is `53 g`D. If hardness is `420 p p m MgCO_(3)` is the amount of `Na_(2)CO_(3)` required to soften `10 L` of hard water is `5.3 g` |
Answer» Correct Answer - A::D `MW of CaCO_(3)=40+12+3xx16=100 gmol^(-1)` `MW of Na_(2)CO_(3)=46+12+3xx16=106 gmol^(-1)` `{:(i.,CaSO_(4)+,Na_(2)CO_(3)to,CaCO_(3),+Na_(2)SO_(4),....(i)),(,x mol,xmol,-,-,),(,-,-,x mol,-,),(ii.,CaCl_(2),+Na_(2)CO_(3)to,CaCO_(3),+2NaCl,....(ii)),(,y mol,y mol,-,-,),(,-,-,y mol,-,):}` iii. `100 p p m CaCO_(3) -=100 g CaCO_(3)` in `10^(6) mL` `=100/100 mol `in `10^(6) mL` Moles of `Na_(2)CO_(3)` required =moles of `CaCO_(3)` `=100/100 mol` in `10^(6) mL` ltbRgt `1/(10^(6))xx10xx10^(3)mL (10 L)` `=1xx10^(-2) mol ` in `10 L` Therefore, moles of `Na_(2)CO_(3)` required `=1xx10^(-2) mol ` in `10 L` `=1xx10^(-2)xx106 g//10 L` `=1.06 g` Similarly, for `100 p p m MgCO_(3)`, `MW of MgCO_(3)=24+12+16xx3=84 g mol^(-1)` `{:(iv.,MgSO_(4)+,Na_(2)CO_(3)to,MgCO_(3),+Na_(2)SO_(4),....(i)),(,x mol,xmol,-,-,),(,-,x mol,,,),(v.,MgCl_(2),+Na_(2)CO_(3)to,MgCO_(3),+2NaCl,....(ii)),(,y mol,y mol,-,-,),(,-,-,,y mol,):}` vi. 420 p p m `MgCO_(3)-=420 g MgCO_(3) ` in `10^(6) mL` -=420/84=5 mol in `10^(6) mL` Moles of `Na_(2)CO_(3)` required =`5xx10^(-2) mol//10 L` `=5.3 g //10 L` |
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1125. |
`H_(2)O_(2)` is a powerful oxidising agent. It is an electron acceptor in acidic as well as in alkaline medium. It can also act as reducing agent towards oxidising agents. In alkaline medium, the reducing nature of `H_(2)O_(2)` is even more effective The bleaching properties of `H_(2)O_(2)` are due to its:A. Unstable natureB. Acidic natureC. Reducing natureD. Oxidising nature. |
Answer» (d) Bleaching action of `H_(2)O_(2)` is due to its oxidising nature. | |
1126. |
Dropping of water over calcium carbide produces ______gas. |
Answer» Correct Answer - Acetylene Acetylene |
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1127. |
How many moles of phosphine are produced when one of the calcium phosphides reacts with water? |
Answer» Correct Answer - 2 `Ca_(3)N_(2)+6H_(2)to3Ca(OH)_(2)+2PH_(3)` |
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1128. |
`100mL` of `H_2O_2` is oxidised by `100mL` of `0.01M KMnO_4` in acidic medium `(MnO_4^(ɵ)` reduced to `Mn^(2+)`). `100mL` of the same `H_2O_2` is oxidised by `VmL` of `0.01M KMnO_4` in basic medium. Hence `V` isA. `100/3 mL`B. `500/3 mL`C. `300/5 mL`D. None |
Answer» Correct Answer - B `{:(MnO_(4)^(ɵ)+5e^(ɵ)toMn^(2+),("acidic")),(MnO_(4)^(ɵ)+3e^(ɵ)toMnO_(2),("basic")):}` `100 mL H_(2)O_(2)=100xx5N MnO_(4)^(ɵ)-=Vxx3N MnO_(2)` `N=500/3 mL` |
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1129. |
`x g` of `H_2O_2` requires `100mL` of `M//5 KMnO_4` in a titration in a solution having `pOH = 1.0` Which of the following is`//`are correct?A. The value of `x`is `1.7 g`B. The value of `x` is `0.34 g`C. `MnO_(4)^(ɵ)` change to `MnO_(4)^(ɵ)`D. `H_(2)O_(2)` change to `O_(2)` |
Answer» Correct Answer - B::C::D `POH=1`, strong basic medium `implies MnO_(4)^(ɵ)toMnO_(4)^(ɵ)` (`n`-factor=`1`) `2overset(Theta)(O)H+H_(2)O_(2)toO_(2)+2H_(2)O+2e^(ɵ)` `mEq of H_(2)O_(2)=mEq of MnO_(4)^(ɵ)` `x/(34//2)xx1000=100xx[1/5xx1]` `x=0.34 g` |
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1130. |
A bottle of `H_2O_2` is labelled as `10 vol H_2O_2. 112mL` of this solution of `H_2O_2` is titrated against `0.04M` acidified solution of `KMnO_4`. Calculate the volume of `KMnO_4` in terms of litre. |
Answer» Correct Answer - 1 `5.6 vol of H_(2)O_(2)=1N=` `10 vol of H_(2)O_(2)=10/5.6 N` `mEq of H_(2)O_(2)=mEq of MnO_(4)^(ɵ)` `10/5.6xx112-=0.04xx5` (`n`factor)`xxV` `V-=1000 mL =1L` |
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1131. |
Which of the following acid is formed when `SiF_(4)` reacts with water ?A. `SiF_(4)`B. `H_(2)SiF_(4)`C. `H_(2)SO_(4)`D. `H_(2)SiF_(6)` |
Answer» Correct Answer - B Silicon tetra fluoride on hydrolysis furnish ortho silicic acid and hydrogen silicofluride. `underset(("Silicon tetra Fluoride "))(3SiF_(4))+underset(("Water"))(4H_(2)O) rarrunderset(("Ortho Silicic acid"))(H_(2)SiO_(4))+underset(("Hydrogen Silico Fluoride "))(2H_(2)SiF_(4))` |
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1132. |
In the following questions, a statement of Assertion (A) is given followed by a corresponding statement of Reason (R) just below it. Of the statements, mark the correct answer as –(A) If both assertion and reason are true, and reason is the true explanation of the assertion.(B) If both assertion and reason are true, but reason is not the true explanation of the assertion.(C) If assertion is true, but reason is false.(D) If both assertion and reason are false.Assertion (A). Chlorine reacts more rapidly with H2 than with D2.Reason (R). D – Cl bond is stronger than H – Cl bond. |
Answer» (B) If both assertion and reason are true, but reason is not the true explanation of the assertion. |
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1133. |
Assertion `:` Reaction between protium and chloride is much faster than between deuterium and chlorine. Reason `:` Enthalpy of dissociation of `D_(2)` is less than `H_(2)`. |
Answer» Correct Answer - C `D_(2)-443.35kJ mol^(-) ` and `H_(2)-435.88 Kj mol ^(-1)`. |
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1134. |
Deuteromethane can be prepared if `D_(2)O` reacts withA. `Al_(4)C_(3)`B. `CaC_(2)`C. Both the aboveD. None of the above |
Answer» Correct Answer - A | |
1135. |
Assertion. Chlorine reacts more rapidly with `H_(2)` than with `D_(2)`. Reason. D-Cl bond is stronger than H-Cl bond. |
Answer» Correct Answer - B Correct explanation. Due to isotope effect, rate of reaction of `Cl_(2)` with `D_(2)` is slower than that with `H_(2)`. |
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1136. |
Heavy water `(D_(2)O)` isA. A product of oxygen and hydrogenB. Water of mineral springsC. Water obtained by repeated distillation and condensationD. Ordinary water containing dissolved salts heavy metals. |
Answer» Correct Answer - C | |
1137. |
Which of the following statements are correct regarding `D_(2)O` and `H_(2)O`? I. `D_(2)O` reacts with `Al_(4)C_(3)` at a faster rate than does `H_(2)O`. II. The freezing point of `D_(2)O`is higher than that of `H_(2)O`. III. NaCl is more solution in `D_(2)O` than in `H_(2)O`. IV. lonic product of `D_(2)O` is smaller than that if `H_(2)O`. Select the correct answer using the codes givem below.A. I and IIB. I and IIIC. II and IIID. II and IV |
Answer» Correct Answer - D `D_(2)O` reacts slower than `H_(2)O` due to greater mass, its freezin point is `3.8^(@)C` . NaCl is less soluble in `D_(2)O` as in `H_(2)O` and `D_(2)O` does not dissociate therefore , its ionic prouduct is smaller than `H_(2)O`. |
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1138. |
When dil. `H_(2)SO_(4)` is electrolysed by using platinum electrodes the gas evolved at cathode isA. `O_(2)`B. `SO_(2)`C. `SO_(3)`D. `H_(2)` |
Answer» Correct Answer - D | |
1139. |
A 30% solution of H2O2 is marketed as……… volume. |
Answer» A 30% solution of H2O2 is marketed as 100 volume. |
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1140. |
How is H2O2 manufactured? |
Answer» BaO2.8H2O(s) + H2SO4(aq.)→ BaSO4(s) + H2O2(aq.) + 8H2O. |
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1141. |
Water obtained by purification with organic ion exchange resins isA. Pure waterB. Free from only `Ca^(2+),Mg^(2+)` ionsC. Free from `HCO_(3)^(-),SO_(4)^(2-)` and `Cl^(-)` ions onlyD. None of these |
Answer» Correct Answer - D Ion exchange resins remove all soluble minerals from water. The hard water is first passed through a bed of cation exchanger, which removes the cations like `Na^(+),Mg^(2+),Ca^(2+)` and others by exchanging with `H^(+)` ions. `underset("Resin")2RH+Ca^(2+)rarr(R)_(2)Ca+2H^(+)` The water coming from cation exchanger is acidic on account of free `H^(+)` ions. This water is then passed through another bed containing anion exchanger. This exchanger removes anions like `Cl^(-),SO_(4)^(2-),NO_(3)^(-)` by exchanging with `OH^(-)` ions. `R-underset("Resin")NH_(3)OH+Cl^(-)rarrR-NH_(3)Cl+OH^(-)` |
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1142. |
What are the uses of Heavy Water? |
Answer» (a) Heavy water is used as a coolant and moderator for neutrons in nuclear reactors. (b) Heavy water is used in the preparation of deuterium and deuterated compounds. (c) It is used as a tracer element in metabolic processes. |
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1143. |
The presence of water is avoided in the preparation of `H_(2)O_(2)` from `Na_(2)O_(2)`. Assign reason. |
Answer» `Na_(2)O_(2)` reacts with water to form NaOH. The reaction is exothermic and the last envolved causes the decomposition of hydrogen peroxide. `2Na_(2)O_(2)+H_(2)O to 3NaO+O_(2)` |
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1144. |
Presence of water is avoided during the preparation of H2O2 from Na2O2 Why? |
Answer» Water present during the reaction, reacts with Na2O2 form NaOH which tends to decompose H2O2. Na2O2 + 2H2O → H2O2 + 2NaOH 2H2O2 → 2H2O + O2 |
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1145. |
An oxide which gives H2O2 on treatment with dilute acid isa) PbO2 b)Na2O2 c) MnO2 d)TiO2 |
Answer» b) Na2O2 dilute acid. |
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1146. |
Which of the following equations depicts the oxidizing nature of H2O2?(a) 2MnO-4 + 6H+ + 5H2O2 → 2Mn2+ + 8H2O + 5O2(b) 2Fe3+ + 2H+ + H2O2 → 2Fe2+ + 2H2O + O2(c) 2I- + 2H ++ H2O2 → I2 + 2H2O(d) KIO4 + H2O2 → KIO3 + H2O + O2 |
Answer» (c) 2I- + 2H ++ H2O2 → I2 + 2H2O |
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1147. |
What is perhydrol? |
Answer» Perhydrol is the trade name for H2O2 which is used as an antiseptic for washing wounds, teeth and ears. |
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1148. |
1000 gram aqueous solution of `CaCO_(3)` contains 10 gram of carbonate. Concentration of solution is:A. `10 "ppm"`B. `100 "ppm"`C. `1000 "ppm"`D. `10000 "ppm"` |
Answer» Correct Answer - D Hardness of solution in pmm =`( 10 xx 10^(6))/(1000)= 10^(4) "ppm"` |
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1149. |
The alum used for purifying water isA. Ferric alumB. Chrome alumC. Potash alumD. Ammonium alum |
Answer» Correct Answer - C `K_(2)SO_(4).Al_(2)(SO_(4))_(3).24H_(2)O` Potash alum is generally used for purifying water. |
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1150. |
The alum used for purifying water isA. Ferric alumB. Chrome alumC. Potash alumD. Ammonium alum. |
Answer» Correct Answer - C Potash alum is generally used for purifying water. |
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