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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.
| 51. |
Which of the following compounds are water soluble ?A. `MgCI_(2)`B. `CaCI_(2)`C. `SrCI_(2)`D. All of these |
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Answer» Correct Answer - D The chlorides, bromides, and iodides of Mg, Ca, Sr, and Ba are ionic, have much lower lattice enthalpies and, hence, lower meltiing points than the fluorides, and are readily soluble in water. The solubility decreases somewhat with increasing atomic number. |
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| 52. |
Which of the following compounds is highly soluble in water ?A. `CaF_(2)`B. `MgF_(2)`C. `BeF_(2)`D. `BaF_(2)` |
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Answer» Correct Answer - C Owing to the high hydration energy of `Be^(2+)` `(-2494kJmol^(-1))` in forming `[Be(H_(2)O)_(4)]^(2+)` beryllium fluoride is very soluble in water. All the other fluorides, `MF_(2)` which are ionic are almost insoluble in water as their as their hydration enthalpies are not able to outweigh their lattice enthalpies. Howerver, The solubility increases slightly with increase in cation size due to the decrease of charge density. |
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| 53. |
Which of the following electronic configuration in the outermost two shells is characteristic of the alkaline earth metals?A. `(n-1)s^(2)p^(6),ns^(2)underline((n-1)s^(2)p^(6))underline(ns^(2))`B. `(n-1)s^(2)p^(6)d^(10),ns^(2) underline((n-1)s^(2)p^(6)d)underline(ns^(2))`C. `(n-1)s^(2)p^(6),ns^(2)np^(1)underline((n-1)s^(2)p^(6)ns^(2)np^(1))`D. `(n-1)s^(2)p^(6),ns^(2)np^(2)underline((n-1)s^(2)p^(6)ns^(2)np^(2))`. |
| Answer» Correct Answer - A | |
| 54. |
The increasing order of basic character of oxides `MgO,SrO,K_(2)O and Cs_(2)O` isA. `MgO lt SrO lt K_(2)O lt Cs_(2)O`B. `CrO lt MgO lt Cs_(2)O lt K_(2)O`C. `Cs_(2)O lt K_(2)O lt SrO lt MgO`D. `K_(2)O lt Cs_(2)O lt SrO lt MgO` |
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Answer» Correct Answer - A Basic character of oxides increases down the group while decreases in a period. |
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| 55. |
Which of the following compounds are soluble in water?A. `Na_(3)PO_(4)`B. `AgF`C. `KCl`D. All of these |
| Answer» Correct Answer - D | |
| 56. |
Alkali earth metals in liq. `NH_(3)` produce a blue coloured solution, due toA. Polarisability of `NH_(3)`B. Charge transferC. `dto d` transitionD. Ammoniated electrons |
| Answer» Correct Answer - D | |
| 57. |
Which of the following is correct regarding the reaction of alkali metals with halogens ?A. Alkali metals react vigorously with halogens to form ionic halides `M^(+)X^(-)`,B. The reactivity of alkali metals towards a particular halogen increases as we move down the group from Li to Cs.C. The reactivity of halogens towards a particular alkali metal decreases from `F_(2) "to" I_(2)`D. All of these. |
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Answer» Correct Answer - D `2M(s)+X_(2)to2M^(+)X^(-)` Reactivity of alkali metals increases down the group because of decrease of ionization enthalpy. |
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| 58. |
Which of the following in incorrect for the hydroxides of alkali metals ?A. They are white crystalline solids.B. These caustic alkalies are the strongest bases known in aqueous solution.C. They readily dissolve in water with the evolution much heat. The solubility in water decreases as move down the group.D. The basis strength of hydroxides increases on moveing down the group. |
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Answer» Correct Answer - C As we move down the group, the solubility of the hydroxides increases because the decrease of lattice energy is more than the decrease of lattice energy is more than the decrease of hydration energy. The hydroxides of Na, K, Rb, and Cs are very soluble in water (more than 100 g per 100 g `H_(2)O " at " 25^(@)C`), but LiOH is much less soluble `(13.0 g//100 g H_(2)O " at " 25^(@)C)`. The evolution of much heat is on account of intense hydration. As we move down the group, the ability of M to release electrons towards O in `M to OH` increases due to the increase of electropositive character. As a result, the M-O bond in MOH can easily break giving `M^(+) "and" OH^(-)` ions. |
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| 59. |
The elements of group II are known as alkaline earth metals. The electronic configuration of these elements . The electronic configuration of these elements is `ns^(2)` and oxidation state is `+2`. They have higher ionization energy than alkali metals in their respective period due to their small size and completely filled s-orbital. These elements give characteristic colour to bunsen flame. magnesium is used in the preparation of Grignard agent (RMgX) which is used in organic chemistry for preparation of sevaral organic compounds like alcohols. acids, hydrocarbons. Q. Brick red colour of flame test is gives byA. SrB. BaC. CaD. Mg |
| Answer» Correct Answer - C | |
| 60. |
The elements of group II are known as alkaline earth metals. The electronic configuration of these elements . The electronic configuration of these elements is `ns^(2)` and oxidation state is `+2`. They have higher ionization energy than alkali metals in their respective period due to their small size and completely filled s-orbital. These elements give characteristic colour to bunsen flame. magnesium is used in the preparation of Grignard agent (RMgX) which is used in organic chemistry for preparation of sevaral organic compounds like alcohols. acids, hydrocarbons. Q. The correct order of 1st ionization energy isA. `Na lt Mg lt Al`B. `Na lt Al lt Mg`C. `Al lt Mg lt Na`D. `Ag lt Na lt Mg` |
| Answer» Correct Answer - B | |
| 61. |
Which of the following is arranged according to increasing basic strength?A. `CaO lt MgO lt lt SrO lt BaO lt BeO`B. `BaO ltSrO lt CaO lt MgO lt BeO`C. `BeO lt MgO lt CaO lt BaO lt SrO`D. `BeO lt MgO lt CaO lt SrO lt BaO` |
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Answer» Correct Answer - D Basic strength of oxides increases down the group. |
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| 62. |
Which of the following compounds are not arranged in correct order as indicated?A. `SrCL_(2) lt CaCl_(2) lt MgCl_(2) lt BeCl_(2)` (increasing of hydrolysis)B. `SrCl_(2)lt CaCl_(2) lt MgCl_(2) lt BeCl_(2) ` (increasing lattice energy)C. `CaSO_(4) lt MgSO_(4) lt BeSO_(4)` (increasing stability)D. `Be(OH)_(2) lt Mg(OH)_(2) lt Ca(OH)_(2)` (increasing solubility) |
| Answer» Correct Answer - C | |
| 63. |
Which of the following is incorrect regarding the solutions of alkali in liquid `NH_(3)` ?A. As the concentration increases above 3 M, the color of solution changes from dark blue to copper-bronze.B. Blue colored solutions as well as bronze-colored solutions are paramagnetic.C. These solutions conduct electricity better than any salt in any liquid and the conductivity is similar to that of pure metals.D. These solutions act as powerful reducing agents for the elements of groups 14, 15, and 16 for many compounds and coordination complexes. They even reduce an aromatic ring. |
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Answer» Correct Answer - B Blue colored dilute solutions are paramagnetic due to the presence of a large number of unpaired ammoniated electrons buit copper-bronze colored solutions are diamagnetic due to the formation of electron clusters in which ammoniated electrons with opposite spins join together `2e^(-)(NH_(3))to[uarr e^(-) (NH_(3))_(x)][darr e^(-) (NH_(3))_(y)]` |
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| 64. |
Which of the following is incorrect regarding the reaction of alkali metals with hydrogen ?A. All the alkali metals react with dihydrogen on heating to form colorless crystalline ionic hydrides `M^(+)H^(-)`.B. The order of reactivity of the alkali metals towards dihydrogen increases as we go down the group.C. The ionic character of the hydrides decreases from Li to Cs.D. The stability of these hydrides decreases from LiH to CsH. |
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Answer» Correct Answer - B The reactivity of alkali metals towards dihydrogen decreases as we move down the group due to decrease of lattice enthalpy with increase of the size of metal ion. Since hydride ion `(H^(-))` is quite small, `Li^(+)` ion on account of smaller size is able to provide high lattice enthalpy. (1) Lithium reacts with dihydrogen at 1073 K while other alkali metals react with dihydrogen at 673 K to form ionic or salt-like hydrides : `2M+H_(2)overset(Delta)to 2M^(+)H^(-)` (3) Cation polarizes the anion and leads to covalent character. As the size of the cation increases, the smaller hydride anion can polarize the cation more easily. consequently, the covalent character increases while the ionic character decreases. (4) Due to the decrease of lattice enthalpy, the stability of the hydrides decreases from LiH to CsH while the reducing power increases. |
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| 65. |
Which of the following statements is correct regarding alkaline earth metals?A. Alkaline earth meals are weaker reducing agents than alkali metalsB. Alkaline earth metal salts are paramagnetic in natureC. Alkaline earth metal salts are more soluble than corresponding alkali meal salts.D. solubility of sulphates of alkaline earth metals increases from top to bottom in the group |
| Answer» Correct Answer - A | |
| 66. |
Which of the following are arranged in correct increasing order of solubilities ?A. `CaCO_(3) lt KHCO_(3) lt NaHCO_(3)`B. `NaHCO_(3) ltKHCO_(3) lt CaCO_(3)`C. `KHCO_(3) lt NaHCO_(3) lt CaCO_(3)`D. `CaCO_(3) lt NaHCO_(3) lt KHCO_(3)` |
| Answer» Correct Answer - D | |
| 67. |
Assertion: Alkaline earth metal oxides are quite stable to heat. Reason: Enthalpies of formation of alkaline earth metal oxides are quite high.A. If both assertion and reason are true and reason is the correct explanation of assertionB. If both assertion and reason are true but reason is not the correct explanation of assertionC. If assertion is true but reason is false.D. If both assertion and reason are false. |
| Answer» Correct Answer - A | |
| 68. |
Which of the following is incorrect regarding s-block elements ?A. They do not occur in the free state.B. They are scarcely distributed in nature in the combined state.C. Alkali metals mostly occur as halides, oxides, silicates, borates, and nitrates.D. Alkaline earth metals mainly occur as silicates, carbonates, sulphates, and phosphates. |
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Answer» Correct Answer - B Both alkali and alkaline earth metals are highly reactive and, hence, do not occur in the free state but are widely distributed in nature in the combined state. |
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| 69. |
How many `s`-block elements are known ?A. 14B. 13C. 12D. 11 |
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Answer» Correct Answer - C There are 6 elements each in group I and 2. Although H having `ns^(1)` configuration and He having `ns^(2)` configuration may be regarded as s-block elements but they are discussed separately because of their properties. |
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| 70. |
What are `s-`block elements? |
| Answer» s-Block elements are those is which the last elestron enters the outermost s-orbital. | |
| 71. |
How alkali metal halides can be prepared? |
| Answer» Alkali metal halides can be prepared by the reaction of the appropriate oxide, hydroxide or carbonate of alkali metals with aqueous hydrohalic acid. | |
| 72. |
The alkali metal halides (MX) are all high melting, colorless crystalline solids which can be conveniently prepared by the reaction of the appropriate ____ with aqueous hydrohalic acids (HX).A. oxideB. hydroxideC. carbonateD. all of these |
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Answer» Correct Answer - D `M_(2)O+2HX to 2MX+H_(2)O` `MOH +HX to MX+H_(2)O` `M_(2)CO_(3)+2HXto 2MX+CO_(2)+H_(2)O` where M is `Li to Cs " and " X is F to I`. Moreover, alkali metals combine directly with halogens under suitable conditions forming corresponding halides. |
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| 73. |
Bone is not an inert and unchanging substance but is continuously being solubilized and redeposited to the extent of ___ mg per day.A. 400B. 350C. 450D. 300 |
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Answer» Correct Answer - A In normal adults, this exchange is in balance, but in elderly people, especially women, there is sometimes a net loss of bone calcium leading to the disease called osteoporosis. All this Ca passes through plasma. |
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| 74. |
Moar conductivites of `Li^(+),Na^(+),K^(+) "and" Rb^(+)` ions in aqueous solutions are in the following order.A. `Rb^(+) gt K^(+) gt Na^(+) gt Li^(+)`B. `Li^(+) gt Rb^(+) gt K^(+) gt Na^(+)`C. `Li^(+) gt Na^(+) gt K^(+)=Rb^(+)`D. `Li^(+) gt Na^(+)=K^(+) lt Rb^(+)` |
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Answer» Correct Answer - A The molar conducity of ions in aqueous solution is inversely related to the dgree of hydration which decreases on moving down the group on accound of the decreases of charge density. |
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| 75. |
The calcium concentration in plasma is regulated at about ___ `mg L^(-1)`.A. 50B. 70C. 100D. 90 |
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Answer» Correct Answer - C It is maintained by two harmones: calcitonin and parathyrod. |
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| 76. |
What is the biological important of `Na^(+) and K^(+)` ions in cell fluids like blood plasma?A. They participate in transmission of nerve signals.B. They regulate the number of red and white blood corpuscles in the cellC. They ca be presence in any amount in the blood since they are absorbed by the cells.D. They regulate the viscosity and colour of the blood |
| Answer» Correct Answer - A | |
| 77. |
Name two important raw materials for the manufacture of cement. |
| Answer» Correct Answer - Clay and lime. | |
| 78. |
Match the column I with column II and mark the appropriate choice. A. `Atoi,Btoii,Ctoiii,Dtoiv`B. `Atoiii,Btoii,Ctoi,Dtoiv`C. `Atoi,Btoiii,Ctoiv,Dtoii`D. `Atoiv,Btoiii,Ctoii,Dtoi` |
| Answer» Correct Answer - D | |
| 79. |
Match the column I with column II and mark the appropriate choice. A. `Atoi,Btoii,Ctoiii,Dtoiv`B. `Atoii,Btoiv,Ctoi,Dtoiii`C. `Atoiv,Btoiii,Ctoii,Dtoi`D. `Atoiv,Btoiii,Ctoii,Dtoi` |
| Answer» Correct Answer - B | |
| 80. |
Match the column I with column II and mark the appropriate choice. A. `Atoi,Btoiv,Ctoii,Dtoiii`B. `Atoiv,Btoi,Ctoiii,Dtoii`C. `Atoii,Btoiii,Ctoi,Dtoiv`D. `Atoiii,Btoii,Ctoiv,Dtoi` |
| Answer» Correct Answer - B | |
| 81. |
Match the column I with column II and mark the appropriate choice. A. `Atoiv,Btoi,Ctoii,Dtoiii`B. `Atoiv,Btoi,Ctoiii,Dtoii`C. `Atoii,Btoiii,Ctoiv,Dtoi`D. `Atoiii,Btoi,Ctoiv,Dtoii` |
| Answer» Correct Answer - D | |
| 82. |
Which of the following is not present in portland cement?A. `Ca_(3)Al_(2)O_(6)`B. `Ca_(3)SiO_(5)`C. `Ca_(2)SiO_(4)`D. `Ca_(3)(PO_(4))_(2)` |
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Answer» Correct Answer - D Phosphate is not a part off composition of portland cement. |
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| 83. |
Match the column I with column II and mark the appropriate choice. A. `Atoiv,Btoi,Ctoiii,Dtoii`B. `Atoi,Btoiii,Ctoii,Dtoiv`C. `Atoiii,Btoii,Ctoi,Dtoiv`D. `Atoiv,Btoi,Ctoii,Dtoiii` |
| Answer» Correct Answer - D | |
| 84. |
The metal ion which plays an important role in muscle contraction isA. `Be^(2+)`B. `Mg^(2+)`C. `Ca^(2+)`D. `Ba^(2+)` |
| Answer» Correct Answer - C | |
| 85. |
The average composition of portland cement isA. `CaO:40-50%,SiO_(2):30-40%,Al_(2)O_(3),Fe_(2)O_(3):10-20%`B. `CaO:50-60%,SiO_(2):20-25%,Al_(2)O_(3):5-10%,MgO:2-3%,Fe_(2)O_(3):1-2% and SO_(3):1-2%`C. `SiO_(2):40-50%,CaO:30-40%,Al_(2)O_(3):10-20%`D. `CaO:50%,SiO_(2):50%` |
| Answer» Correct Answer - B | |
| 86. |
Which nitrate will decompose to give `NO_(2)` on heating?A. `NaNO_(3)`B. `KNO_(3)`C. `RbNO_(3)`D. `LiNO_(3)` |
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Answer» Correct Answer - D Only `LiNO_(3)` gives `NO_(2)` on heating. All other nitrates given oxygen. ,brgt `4LiNO_(3)overset(Delta)to 2Li_(2)O+4NO_(2)+O_(2)` `2NaNO_(3)+ overset(Delta)to 2NaNO_(2)+O_(2)` |
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| 87. |
Lithium salts are mostly hydrated like `LiCl*2H_(2)O` due toA. maximum ionisation enthalpyB. maximum degree of hydration of `Li^(+)`C. maximum hygroscopic natureD. maximum chemical reactivity. |
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Answer» Correct Answer - B `Li^(+)` has maximum degree of hydration due to smallest size in the grou phence its salts are mostly hydrated. |
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| 88. |
Which decomposes on heating-A. NaOHB. KOHC. LiOHD. RbOH |
| Answer» Correct Answer - C | |
| 89. |
Which cell is used for manufacture of sodium hydroxide. |
| Answer» Castner-kellner cell | |
| 90. |
Solvay process is used for the manufacture ofA. Sodium metalB. Washing sodaC. Bleaching powderD. Quick lime |
| Answer» Correct Answer - B | |
| 91. |
Which of the following is widely used for treating ice on roads, particularly in very cold countries?A. `BaCl_(2)`B. `CaCl_(2)`C. `MgCl_(2)`D. `SrCl_(2)` |
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Answer» Correct Answer - B Because as 30% eutectic mixture of `CaCl_(2)//H_(2)O` freezes at `-55^(@)C` compared with `NaCl//H_(2)O` at `-18^(@)C,CaCl_(2)` is also used to make concrete set more quickly and to improve its strenght and as brine in refrigeration plants. A minor use is in laboratories as a desiccant (dryign agent). Anhydrous `MgCl_(2)` is important in the electrolytic method for extracting Mg. |
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| 92. |
In the manufacture of sodium hydroxide by product obtained isA. `O_(2)`B. `Cl_(2)`C. `Na_(2)CO_(3)`D. `NaCl` |
| Answer» Correct Answer - B | |
| 93. |
The hydroxide of ____is obtained by treating the metal with cold water.A. CaB. SrC. BaD. all of these |
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Answer» Correct Answer - D The hydroxides of strongly electropositive group 2 elements Ca, Sr, and Ba are obtained either by treating the metal with cold water or by reacting the corresposing oxides with water `M+2H_(2)OtoM(OH)_(2)+H_(2)` `MO+H_(2)OtoM(OH)_(2)` `M=Ca,S and Ba` `Be(OH)_(2)` and `Mg(OH)_(2)` being isoluble are obtained from water soluble compounds by reaction with alkalies `MSO_(4)+2NaOHtoM(OH)_(2)+Na_(2)SO_(4)(aq.)` `M=Be and Mg` |
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| 94. |
Which of the following hydroxides is the most soluble in water ?A. `Mg(OH)_(2)`B. `Ba(OH)_(2)`C. `Ca(OH)_(2)`D. `Sr(OH)_(2)` |
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Answer» Correct Answer - B Both lattice enthalpy and hydration enthalpy decrease on moving down the group due to increase in the size of the cation but the lattice enthalpy decreases more rapidly than the hydration enthalpy and, hence, the solubility of group 2 hydroxides in water increases on moving down the group However, group 2 hydroxides are less soluble in water as compared to the alkali metal hydroxides. `Mg(OH)_(2)` is weakly basic and is used to treat acid indigestion. the other hydroxides are strong bease. `Ca(OH)_(2)` is called slaked time. |
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| 95. |
Magnesium can be obtanied byA. reducing MgO with cokeB. reducing Mg salt solution with FeC. electrolysis of fused mg saltD. electrolysis of `Mg(NO_(3))_(2)` solution. |
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Answer» Correct Answer - C It is usually extracted by the elctrolysis of fused oxide or fused anhydrous chloride: At cathode `Mg^(2+)+2e^(-)rarrMg` |
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| 96. |
The alkali metals are soft due to- |
| Answer» Because they have weak metallic bond. | |
| 97. |
Why lithium carbonate is not stable to heat? |
| Answer» Lithium being small in size polarises a large `CO_(3)^(2-)` ion leading to the formation of more stable `Li_(2)O` and `CO_(2)` on heating, due to this tendency of lithium, lithium carbonate is not stable. | |
| 98. |
Which of the following oxides react exothermically with water forming hydroxides ?A. CaOB. SrOC. BaOD. All of these |
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Answer» Correct Answer - D All these oxides except BeO (covalent) are basic in nature and react with water to form hydroxides. CaO, SrO, and BaO react exothermicaly with water forming hydroxides: `MO+H_(2)OtoM(OH)_(2)` |
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| 99. |
On heating below 373 K, washing soda loses ____molecules of water of crystallization.A. nineB. eightC. tenD. seven |
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Answer» Correct Answer - A Thus, monohydrate is formed `Na_(2)CO_(3).10H_(2)Ooverset("below "373K)toNa_(2)CO_(3).H_(2)O+9H_(2)O` above 373 K the monohydrate becomes completely anhydrous and changes to a white powder called soda ash, which dows not decompose further: `Na_(2)CO_(3).H_(2)Ooverset("above "373K)toNa_(2)CO_(3)+H_(2)O` |
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| 100. |
sodium carbonate commonly known as washing soda is manufactured byA. ammonia-soda processB. Solvay-ammonia processC. Solvay processD. all of these |
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Answer» Correct Answer - D These are different names of the same method. |
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