NCERT Class 11 Chemistry Chapter 10 S Block Elements Very Short Answer Questions

NCERT Solutions For Class 11 Chemistry Chapter 10 S Block Elements Very Short Question And Answers

Question 1. Explain why sodium carbonate is used in fire extinguishers.
Answer: In fire extinguishers, Na₂CO₃ is used as it reacts with dil. H₂SO₄ to produce CO₂

Question 2. Why docs sodium hydrogen carbonate called baking soda?
Answer: NaHCO₃ is an important ingredient in baking powder. Thus, it is also called baking soda.

Question 3. Name a bivalent element whose oxide is soluble in excess NaOH solution.
Answer:  Beryllium; BeO + 2NaOH→ Na₂BeO₂ + H₂O

Question 4. Which of the alkali metals exhibits abnormal behavior?
Answer: Lithium

S-Block Elements Very Short Answer Questions Class 11

Read and Learn More NCERT Class 11 Chemistry Very Short Answer Questions

Question 5. Which alkali metal is most abundant in the earth’s crust?
Answer: Sodium (Na)

Question 6. What type of crystal lattice is formed by the alkali metals?
Answer:  Alkali metals form a body-centered cubic lattice

Question 7. Name an alkali metal that is used in Lassaigne’s test for the detection of nitrogen, sulfur, and halogen in the organic compounds.
Answer: Sodium

Question 8. Write the general electronic configuration of group-2 elements.
Answer: Electronic configuration: [Inert gas] ns²

Question 9. Which element of group 2 shows abnormal behavior?
Answer: Beryllium (Be) shows abnormal behavior

NCERT Class 11 Chemistry Chapter 10 S-Block Elements Very Short Answer Questions

Question 10. Why CaF₂ is considered the most important fluoride salt among all the fluoride salts of alkaline earth metals?
Answer:  CaF₂ is the most important source for the preparation of fluorine

Question 11. Which out of LIF of Lil is more covalent?
Answer:  Lil is more covalent.

Question 12. Which alkali metal carbonate easily liberates CO₂ on heating?
Answer: Li₂CO₃ easily liberates CO₂ on heating.

Question 13. Which alkali metal chloride imparts violet color to the bunsen burner flame?
Answer: Potassium chloride (KCl)

Question 14. Which alkali metal hydride is used as a source of hydrogen for filling up meteorological balloons?
Answer: Lithium hydride (LiH).

Question 15. Name the products formed in the following reaction. Explain Lil + KF→? + ?
Answer: LiF and KI. The larger K⁺ ion stabilizes the larger I^– ion while the smaller Li⁺ ion stabilizes the smaller F- ion.

Question 16.  What is water glass?
Answer: Sodium silicate (NaOSiO₃).

Question 17. Which alkali metal combines with nitrogen to form the corresponding nitride?
Answer: Lithium (Li).

Question 13. What are the raw materials used for the manufacture of sodium carbonate by the Solvay process?
Answer: The raw materials are NaCl, CaCO and NH₃.

Question 18. Which out of the Na₂CO₃ solution & NaHCO₃ solution, changes the color of phenolphthalein into pink?
Answer: Na₂CO₃ solution.

Question 19. What is the main ingredient of baking powder?
Answer: Sodium bicarbonate (NaHCO₃).

Question 20. Which compound is used to treat the flue gases from coal and oil-fired power stations and to remove SO₂ and H₂SO₄ responsible for acid rain?
Answer: Na₂CO₃.

Question 21. What are the ingredients of the fusion mixture that is used in dry tests in inorganic analysis?
Answer: K₂CO₃ and Na₂CO₃

Question 22. Which alkaline earth metal is the most abundant in the earth’s crust?
Answer: Calcium (Ca).

Question 23. Which alkaline earth metal is radioactive?
Answer: Radium (Ra).

Very Short Answer Questions for Class 11 Chemistry S-Block Elements

Question 24. Name the metal of group-2 which is used to prepare Grignard reagent.
Answer: Magnesium (Mg).

Question 25. Name the element of group 2 that resembles lithium in characteristics.
Answer: Magnesium (Mg).

Question 26. Which alkaline earth metals do not impart any color to the flame of a Bunsen burner?
Answer: Be anil Mg.

Question 27. Name an alkaline earth metal compound that can be used as a portable source of hydrogen.
Answer: Calcium hydride (CaH₂).

Question 28. Which Gr-2 metal forms covalent compounds?
Answer: Beryllium (Be).

Question 29. Which Gr-2 metal burns readily when exposed to air?
Answer: Barium (B a).

Question 30. Which alkaline earth metal reacts with alkali to form hydrogen gas?
Answer: Beryllium (Be).

Question 31. What is the composition of the alloy, electron?
Answer: 95% of Mg+ and 5% of Zn.

S-Block Elements Class 11 Very Short Answer Questions

Question 32. Which reagent is used to analyze Ca²⁺ and Mg²⁺ ions quantitatively?
Answer: EDTA (Ethylenediaminetetraacetic acid).

Question 33. What is the medicinal name of the aqueous solution of Mg(OH)₂?
Answer: Milk of magnesia.

Question 34. What is anhydrous?
Answer: Magnesium perchlorate, Mg(ClO₄)₂ is known as anhydrous.

S-Block Elements Chapter 10 Short Answer Solutions Class 11

Question 35. How will you distinguish between BeSO₄ & BaSO₄?
Answer: BeSO₄ is water soluble but BaSO₄ is insoluble in water.

Question 36. Which out of MgCO₃, SrCO_3, and BaCO₄, possesses the highest thermal stability?
Answer: BaCO₄ has the highest thermal stability.

Question 37. Distinguish between Be(OH)₂ and Ba(OH)₂
Answer: Be(OH)₂ is soluble in caustic soda solution while Ba(OH)2 is insoluble in it.

Question 38. Why is BeCl₂ soluble in organic solvents?
Answer: BeCl₂ is covalent.

Question 39. Which Gr-2 metal carbonate is unstable in the air?
Answer: BeCO₃.

Question 40. Which alkaline earth metal sulfate is useful in diagnosing stomach ulcers by X-ray?
Answer: BaSO₄ (in ‘barium meal’ X-ray).

Question 41. BeO is covalent but still, it has a much higher melting point— mention the reason.
Answer: This is due to its polymeric structure.

Question 42. What is the difference between lime water and milk of lime?
Answer: Mg²⁺

Question 43. Write a reaction by which BeCl₂ can be prepared.
Answer:

NCERT Class 11 Chemistry S-Block Elements VSAQ Solutions

Question 44. What is the composition of soda lime used for the preparation of hydrocarbons in the laboratory?
Answer: NaOH and CEO
.
Question 45. ED Name two acidic oxides which react similarly with calcium hydroxide [Ca(OH)₂].
Answer: CO₂ and SO₂.

Question 46. Which alkaline earth metal oxide is used as a flux in metallurgy to remove siliceous impurities?
Answer: Calcium oxide (CaO)

Question 47. What is the commercial name of the disinfectant powder obtained when Cl2 reacts with slightly moist slaked lime at 40°C?
Answer: Bleaching powder.

Question 48. What is Plaster of Paris?
Answer: Hemihydrate of calcium sulphate, (CaSO₄)₂-H₂O is called Plaster of Paris.

Question 49. What type of impurities in gypsum should be avoided in preparing Plaster of Paris from it?
Answer: Carbonaceous impurities are to be avoided.

Question 50. Why KNO₃ is used instead of NaNO₃ in gunpowder?
Answer: NaNO₃ is deliquescent. Hence, KNO₃ is preferred over NaNO₃ for the preparation of gunpowder.

Question 51. What do you mean by ‘black ash
Answer: A mixture of sodium carbonate (Na₂CO₃) and calcium sulfide (CaS) is called black

Question 52. What happens when magnesium is heated with | acetylene at 875K?
Answer: Magnesium on heating with acetylene at 875K forms magnesium carbide (Mg₃C₂)

Question 53. Write the composition of gunpowder.
Answer: Gunpowder is an explosive mixture containing KNO₃ along with charcoal and sulfur

Class 11 Chemistry Chapter 10 S-Block Elements Short Answer Questions

Question 54. Why is Na₂S₂O₃ used in photography?
Answer: In photography, Na₂S₂O₃ is used to dissolve the unexposed AgBr.

Question 55. The affinity of sodium towards water is used in drying benzene. Explain.
Answer: Sodium does not react with benzene. Hence it can be used effectively for drying benzene.

Question 56.  Name a pair of elements that exhibits a diagonal relationship.
Answer:  Lithium (Li) and magnesium (Mg) CO₂

Question 57. Name an alkaline earth metal.
Answer: Calcium (ca)

Question 58. Write the balanced equation for the reaction when water is added to calcium carbide.
Answer: CaC₂ + 2M₂O →MC=CH + Ca(OH)₂

Question 59. Which alkali metal ion has the highest polarising power?
Answer: Li⁺

Question 60. What are the common oxidation states exhibited by group-1 and group-2- 2 metals respectively?
Answer: +2 And +1 respectively

Question 61. Name the alkali metals which form superoxides when heated with excess oxygen.
Answer: K, Rb, and cs

Question 62. Which one is the lightest and which one is the heaviest of all the metals?
Answer: Lithium (Li) and Osmium(os) respectively

Question 63. What is the composition of the white powder obtained when metallic magnesium is burnt in the air?
Answer: A mixture of MgO and Mg₃N₂

Question 64. Name two metals of group 2 which do not impart any color to the flame.
Answer: Mg and Be

Question 65. Which alkali metal cannot be stored in kerosene?
Answer: Li

Question 66. Which alkali metal is used as a scavenger in metallurgy to remove O₂ and N₂ gases?
Answer: Li

Question 67. Which Gr-2 metal carbide reacts with water to produce methane?
Answer: Be₂ C

S-Block Elements Chapter 10 NCERT Very Short Answer Questions

Question 68. In an aqueous solution, which alkali metal ion has the lowest mobility?
Answer: Li⁺

Question 69. Which is the most abundant alkaline earth metal in the earth’s crust?
Answer: Calcium

Question 70. Name one group-2 metal.
Answer: Chlorophyll

Question 71. Which alkali metal ion forms a stable complex with 18- crown-6
Answer: Potassium(K)

Question 72. Which alkaline earth metal is largely used as a lightweight construction metal?
Answer: Mg

Question 73. Which alkaline earth metal forms an organometallic compound known as Grignard reagent?
Answer: Mg

NCERT Solutions Class 11 Chemistry Chapter 10 S-Block Elements VSAQ

Question 74. Which alkali and alkaline earth metals are radioactive?
Answer: Fr and Ra

Question 75.  The salts of which alkali metals are commonly hydrated?
Answer: Li

Question 76. Which alkali metal acts as the strongest reducing agent in aqueous solution?
Answer: Li

Question 77. Which is the least stable alkali metal carbonate?
Answer: Li₂CO₃

Question 78. What is baryta water?
Answer: Ba(OH ₂ solution

Question 79. Which alkaline earth metal hydroxide is most soluble in water?
Answer: Ba(OH)₂

Question 80. Which alkaline earth metal imparts crimson color to flame?
Answer: Srcl₂

Question 81. BeO is covalent and still has high melting points — why?
Answer: It is polymeric

Question 82. What is anhydrous?
Answer: Magnesium perchlorate Mg(ClO₄)₂

Question 83. Which alkaline earth metal carbonate can be kept only in an atmosphere of CO₂?
Answer: BeCO₃

Question 84. Which alkaline earth metal chloride is used as a desiccant in the laboratory?
Answer: CaCl₂

Very Short Answer Solutions for S-Block Elements Class 11 Chemistry

Question 85. The basic strength of which alkali metal hydroxide is the highest?
Answer: CsOH

Question 86. Which alkaline earth metal hydroxide is amphoteric?
Answer: Be(OH)₂

Question 87. How will you distinguish between Ba(OH)₂ and Be(OH)₂?
Answer: Be(OH)₂ dissolves in alkali but Ba(OH)₂ does not

Question 88. What are the raw materials used for the manufacture of washing soda by the Solvay process?
Answer: NaCl, CaCO₃ and NH₃

Question 89. What is soda ash?
Answer: . Anhydrous Na₂CO₃

Question 90. Which alkaline earth metal hydroxide and alkali metal carbonate are used for softening hard water?
Answer: Ca(OH)₂ and Na₂CO₃;

Question 91. What is the formula of Plaster of Paris?
Answer: 2CaSO₄ .H₂O

Question 92. What is dead burnt plaster?
Answer: Anhydrous CaSO₄;

Question 93. Which alkaline earth metal carbonate is used as an ingredient of chewing gum?
Answer: CaCO₃

Question 94. What is a fusion mixture?
Answer: A mixture of Na₂CO₃ and K₂CO₃

Question 95. What is the most abundant source of sodium chloride?
Answer: Seawater

Question 96. For which of its chief properties is Plaster of Pariswide used?
Answer: On mixing with water, it forms a plastic mass which sets into a hard mass within 5 to 15 minutes;

Question 97. What is used for making blackboard chalks?
Answer: CaCO₃

Question 98. Which compound is generally used for the detection of CO₂ in the laboratory?
Answer: Lime water [Ca(OH)₂]

Question 99. What is the diagonal relationship? Give one example
Answer:

See ‘General Discussion on s -block elements

Very Short Answer Questions for Class 11 Chemistry Chapter 10 S-Block Elements

Question 100. Which of the alkaline earth metal hydroxides are amphotericin in nature?
Answer:

Beryllium hydroxide [Be(OH)₂] is amphoteric in nature

Class 11 Chemistry S-Block Elements VSAQ

Question 101. What is hydrolysis?
Answer:

Calcium hydride [CaH₂] is known as hydrolytic

Question 102. Find out the oxidation state of sodium in Na₂O₂.
Answer:

Let the oxidation state of Na be x. The oxidation state of oxygen in the peroxides is -1

2x + 2(-1) = 0; 2x = 2,x= +1.

Question 103. Which two alkaline earth metals cannot be identified by flame test?
Answer:

Beryllium (Be) and magnesium (Mg) cannot be identified by flame test

Question 104. Magnesium occurs in nature largely as MgCO₃but beryllium never occurs as BeCO₃. Explain.
Answer:

The strong polarising power of Be²⁺ ion makes BeCO₃ unstable;

Question 105. Out of Na and Mg which one has a higher second ionization enthalpy? Why?
Answer:

The second ionization enthalpy of Na is higher than that of Mg;

Question 106. The chloride of a metal is soluble in an organic solvent. The chloride can be CaCl₂, NaCl, MgCl₂, BeCl₂
Answer: BeCl₂

Question 107. Why does common salt become wet in the rainy season?
Answer:

Due to the absorption of aerial moisture by deliquescent impurities like MgCl₂, CaCl_2, etc;

S-Block Elements Chapter 10 Very Short Answer Q&A Class 11

NCERT Solutions For Class 11 Chemistry Chapter 10 S Block Elements Fill In The Blanks

Question 1. _____________ has no d-orbital in its valence shell.
Answer: Lithium

Question 2. _____________ reacts with nitrogen to give nitrides.
Answer: Lithium

Question 3. _____________ imparts a golden-yellow color to the flame.
Answer: Sodium

Question 4. Potassium, in reaction with dioxygen, produces _____________
Answer: KO₂

Question 5. The outermost electronic configuration of the radioactive alkali metal is _____________
Answer: 7s¹

Question 6. The bicarbonate salt_____________ of does not exist in solid state.
Answer: Lithium

Chapter 10 S-Block Elements VSAQ Class 11 NCERT Solutions

Question 7. Ionic conductance of Li+ ion in aqueous solution is lowest _____________ is highest
Answer: Hydration

Question 8. _____________ion has maximum polarising power
Answer: Li⁺

Question 9. _____________ is the most abundant alkali metal in Earth’s
Answer: Sodium

Question 10. The basicity of the alkali metal hydroxides _____________ down the group.
Answer: Increases

Question 11._____________ is used as a source of oxygen in submarines, space shuttles, and oxygen masks.
Answer: KO₂

Question 12. The alkali metals combine with mercury to give_____________
Answer: Amalgams

Question 13. The alkali metals exist as_____________ lattices having cordination number 8.
Answer: Body Center cubic

Question 14. Lil _____________ is more soluble than KI in ethanol.
Answer: More

Question 15. K₂CO₃ cannot be produced by the Solvay process because _____________ does not get precipitated in the aqueous solution.
Answer: KHCO₃

Question 16. _____________ and _____________ do not respond to flame test.
Answer: Be,  Mg

Question 17. _____________ ion exhibits maximum does not respond tendency to complexes.
Answer: Be²⁺

Question 18. Only _____________ can displace hydrogen from dilute HNO₃
Answer: Mg

NCERT Class 11 Chemistry Chapter 10 S-Block Elements VSAQ

Question 19. Common salt gets wet due to the presence of _____________ as impurity.
Answer: MgCl₂

Question 20. Hydration enthalpy of Mg²⁺ is _____________ Ca²⁺. as than that of
Answer: Greater

Question 21. Hydrolysis of calcium carbide produces _____________
Answer: Acetylene

Question 22. The commercial name of _____________is hydrolith
Answer: CaH₂,

Question 23. BeCO₃ is stable only in an atmosphere of _____________
Answer: CO₂

NCERT Class 11 S-Block Elements Short Answer Questions

Question 24. Lime water is a transparent aqueous solution of _____________
Answer: Ca(OH)₂

Question 25. The second ionization enthalpy of the alkaline earth metals is _____________ than their first ionization enthalpy.
Answer: Greater

Question 26. _____________ is used to prepare Grignard reagents
Answer: Greater

NCERT Class 11 Chemistry Chapter 10 S-Block Elements VSAQ

Question 27. The melting point of the alkaline earth metals is _____________ than that of alkali metals
Answer: Mg

Question 28. Between Ca and Na, _____________ is used to dehydrate alcohols
Answer: Ca

Question 29. Among the alkaline earth metals, _____________ is abundant in the earth’s crust.
Answer: Ca

Question 30. Temperature of the mixture of _____________  -54°C. Is most and ice is about
Answer: CaCl²⁺