Class 11 Chemistry MCQ Chapter 10 The s-Block Elements
Need help with Class 11 Chemistry MCQ Chapter 10 The s-Block Elements English Medium? This page offers a complete set of important MCQ questions with answers for AHSEC Higher Secondary First Year students who want to improve their Chemistry preparation.
In The s-Block Elements chapter, students study the first two groups of the modern periodic table and their unique properties. The chapter covers alkali metals and alkaline earth metals, their occurrence, extraction, physical and chemical characteristics, important compounds, and practical applications. It also explains periodic trends and the reasons behind the similarities and differences among these elements.
These MCQs are prepared according to the latest AHSEC syllabus and are useful for quick revision before examinations. By practicing these objective questions, students can strengthen their understanding of important concepts and become familiar with the types of questions commonly asked in exams.
Whether you are revising for a classroom test, annual examination, or the AHSEC HS First Year Board Exam, these MCQ solutions will help you learn the chapter more effectively and boost your confidence.
Part II
Class 11 Chemistry MCQ Chapter 10 The s-Block Elements
Selected VSA & MCQ
I. Very Short Answer Questions (VSA)
Q: Which groups of the periodic table constitute the s-block elements?
Ans: Group 1 and Group 2 elements constitute the s-block elements.
Q: Why are s-block elements so called?
Ans: s-block elements are so called because their valence electrons enter the s-orbital.
Q: Which elements belong to Group 1 of the periodic table?
Ans: Lithium, sodium, potassium, rubidium, caesium and francium belong to Group 1.
Q: What are alkali metals?
Ans: The elements of Group 1 are called alkali metals.
Q: Why are Group 1 elements called alkali metals?
Ans: They are called alkali metals because their oxides and hydroxides are strongly basic
and soluble in water.
Q: Which elements belong to Group 2 of the periodic table?
Ans: Beryllium, magnesium, calcium, strontium, barium and radium belong to Group 2.
Q: What are alkaline earth metals?
Ans: The elements of Group 2 are called alkaline earth metals.
Q: Why are Group 2 elements called alkaline earth metals?
Ans: They are called alkaline earth metals because their oxides are alkaline in nature and
occur naturally in the earth’s crust.
Q: Which alkali metal shows diagonal relationship with magnesium?
Ans: Lithium shows diagonal relationship with magnesium.
Q: Why does lithium show anomalous behaviour?
Ans: Lithium shows anomalous behaviour due to its small size and high polarising
power.
Q: Which is the most abundant alkali metal in the earth’s crust?
Ans: Sodium is the most abundant alkali metal in the earth’s crust.
Q: Name the most abundant alkaline earth metal in the earth’s crust.
Ans: Calcium is the most abundant alkaline earth metal in the earth’s crust
Q: Why are alkali metals highly reactive?
Ans: Alkali metals are highly reactive because they have low ionisation enthalpy and can
easily lose one electron.
Q: Why are alkali metals not found free in nature?
Ans: Alkali metals are highly reactive, so they are not found free in nature.
Q: Which alkali metal is stored under kerosene oil?
Ans: Sodium and potassium are stored under kerosene oil.
Q: Why is lithium less reactive than sodium?
Ans: Lithium is less reactive than sodium because it has higher ionisation enthalpy.
Q: What is the nature of oxides formed by alkali metals?
Ans: The oxides formed by alkali metals are strongly basic.
Q: Which alkali metal forms only normal oxide?
Ans: Lithium forms only normal oxide.
Q: Which alkali metals form peroxides and superoxides?
Ans: Sodium forms peroxide, while potassium, rubidium and caesium form superoxides.
Q: State one use of baking soda.
Ans: Baking soda is used in baking powder.
Q: What is caustic soda?
Ans: Caustic soda is sodium hydroxide ((NaOH)).
Q: Name one important compound of calcium.
Ans: Calcium carbonate is an important compound of calcium.
Q: What is quick lime?
Ans: Quick lime is calcium oxide ((CaO)).
Q: State one use of plaster of Paris.
Ans: Plaster of Paris is used for making casts for fractured bones.
Q: What is the flame colour shown by sodium?
Ans: Sodium imparts golden yellow colour to the flame.
Q: What is the flame colour shown by potassium?
Ans: Potassium imparts violet colour to the flame.
Q: What is the flame colour shown by calcium?
Ans: Calcium imparts brick red colour to the flame.
Q: Why do alkali metals impart colour to the flame?
Ans: Alkali metals impart colour to the flame due to excitation of their valence electrons.
Q: What is the nature of hydroxides of alkaline earth metals?
Ans: The hydroxides of alkaline earth metals are basic in nature.
Q: Which alkaline earth metal does not impart colour to flame?
Ans: Beryllium and magnesium do not impart colour to flame.
II. Multiple Choice Questions (MCQs)
Q: The s-block elements belong to —
(a) Groups 13 and 14
(b) Groups 15 and 16
(c) Groups 1 and 2
(d) Groups 17 and 18
Ans: (c) Groups 1 and 2
Q: s-block elements are so called because their valence electrons enter the —
(a) p-orbital
(b) d-orbital
(c) f-orbital
(d) s-orbital
Ans: (d) s-orbital
Q: Group 1 elements are known as —
(a) Halogens
(b) Noble gases
(c) Alkali metals
(d) Transition metals
Ans: (c) Alkali metals
Q: Group 2 elements are called —
(a) Halogens
(b) Alkaline earth metals
(c) Lanthanoids
(d) Actinoids
Ans: (b) Alkaline earth metals
Q: Which alkali metal shows diagonal relationship with magnesium?
(a) Sodium
(b) Potassium
(c) Lithium
(d) Caesium
Ans: (c) Lithium
Q: Lithium shows anomalous behaviour due to its —
(a) Large size
(b) High metallic character
(c) Small size and high polarising power
(d) Low ionisation energy
Ans: (c) Small size and high polarising power
Q: The most abundant alkali metal in the earth’s crust is —
(a) Lithium
(b) Sodium
(c) Potassium
(d) Caesium
Ans: (b) Sodium
Q: The most abundant alkaline earth metal in the earth’s crust is —
(a) Magnesium
(b) Calcium
(c) Barium
(d) Strontium
Ans: (b) Calcium
Q: Alkali metals are highly reactive because they have —
(a) High ionisation enthalpy
(b) Low electron affinity
(c) Low ionisation enthalpy
(d) High electronegativity
Ans: (c) Low ionisation enthalpy
Q: Alkali metals are not found free in nature because they are —
(a) Radioactive
(b) Highly reactive
(c) Heavy metals
(d) Inert
Ans: (b) Highly reactive
Q: Sodium is generally stored under —
(a) Water
(b) Alcohol
(c) Kerosene oil
(d) Benzene
Ans: (c) Kerosene oil
Q: Sodium reacts with water to produce —
(a) Sodium oxide and oxygen
(b) Sodium hydroxide and hydrogen
(c) Sodium peroxide and oxygen
(d) Sodium carbonate and hydrogen
Ans: (b) Sodium hydroxide and hydrogen
Q: Which alkali metal forms only normal oxide?
(a) Sodium
(b) Potassium
(c) Caesium
(d) Lithium
Ans: (d) Lithium
Q: Sodium mainly forms —
(a) Superoxide
(b) Peroxide
(c) Normal oxide only
(d) Hydroxide only
Ans: (b) Peroxide
Q: Potassium forms —
(a) Normal oxide
(b) Peroxide
(c) Superoxide
(d) Hydroxide
Ans: (c) Superoxide
Q: Baking soda is chemically known as —
(a) Sodium hydroxide
(b) Sodium chloride
(c) Sodium carbonate
(d) Sodium hydrogen carbonate
Ans: (d) Sodium hydrogen carbonate
Q: Baking soda is used in —
(a) Whitewashing
(b) Baking powder
(c) Electroplating
(d) Photography
Ans: (b) Baking powder
Q: On heating, baking soda produces —
(a) Sodium chloride
(b) Sodium hydroxide
(c) Sodium carbonate
(d) Sodium oxide
Ans: (c) Sodium carbonate
Q: Plaster of Paris is —
(a) Calcium oxide
(b) Calcium hydroxide
(c) Calcium sulphate hemihydrate
(d) Calcium carbonate
Ans: (c) Calcium sulphate hemihydrate
Q: Plaster of Paris is used for —
(a) Water purification
(b) Electrolysis
(c) Making casts for fractured bones
(d) Manufacture of glass
Ans: (c) Making casts for fractured bones
Q: Sodium imparts which colour to the flame?
(a) Violet
(b) Brick red
(c) Golden yellow
(d) Apple green
Ans: (c) Golden yellow
Q: Potassium imparts which colour to the flame?
(a) Violet
(b) Blue
(c) Brick red
(d) Crimson red
Ans: (a) Violet
Q: Calcium imparts which colour to the flame?
(a) Golden yellow
(b) Brick red
(c) Violet
(d) Green
Ans: (b) Brick red
Q: Assertion (A): Alkali metals are highly reactive.
Reason (R): Alkali metals have low ionisation enthalpy.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true but R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
Ans: (a) Both A and R are true and R is the correct explanation of A
Q: Assertion (A): Sodium and potassium are stored under kerosene oil.
Reason (R): They react readily with air and moisture.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true but R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
Ans: (a) Both A and R are true and R is the correct explanation of A
Q: Assertion (A): Lithium shows anomalous behaviour among alkali metals.
Reason (R): Lithium has very small atomic size and high polarising power.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true but R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
Ans: (a) Both A and R are true and R is the correct explanation of A
Q: Assertion (A): Baking soda is used in baking powder.
Reason (R): Baking soda releases carbon dioxide on heating.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true but R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
Ans: (a) Both A and R are true and R is the correct explanation of A
Q: Assertion (A): Ice is used to prepare slaked lime.
Reason (R): Quick lime reacts with water to form calcium hydroxide.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true but R is not the correct explanation of A
(c) A is false but R is true
(d) A is true but R is false
Ans: (c) A is false but R is true
Q: Assertion (A): Beryllium and magnesium do not impart colour to flame.
Reason (R): Their electrons require high energy for excitation.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true but R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
Ans: (a) Both A and R are true and R is the correct explanation of A
Q: Assertion (A): Group 2 elements are called alkaline earth metals.
Reason (R): Their oxides are alkaline and occur naturally in earth’s crust.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true but R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
Ans: (a) Both A and R are true and R is the correct explanation of A. 0 0 0
