Class 11 Chemistry MCQ Chapter 3 Classification of Elements and Periodicity in Properties
Are you searching for Class 11 Chemistry MCQ Chapter 3 Classification of Elements and Periodicity in Properties English Medium? If yes, then this article will help you prepare better for your AHSEC Higher Secondary First Year Chemistry examination.
The chapter Classification of Elements and Periodicity in Properties explains how elements are arranged in the modern periodic table and how their properties change across periods and groups. Students will learn about the history of element classification, modern periodic law, periodic trends, atomic radius, ionization enthalpy, electron affinity, electronegativity, and the chemical behavior of elements. Understanding these concepts is important for studying both inorganic and physical chemistry.
The MCQs provided here are based on the latest AHSEC syllabus and examination pattern. These objective questions are useful for quick revision, concept building, and exam preparation. Regular practice can help students understand periodic trends more clearly and improve their performance in examinations.
Whether you are preparing for class tests, annual exams, or the AHSEC HS First Year Final Examination, these MCQ questions and answers will help you revise the chapter effectively and score higher marks.
Part: I
Classification of Elements and Periodicity in Properties
Selected VSA & MCQ
I. Very Short Answer Questions (VSA)
Q What is periodic classification?
Ans: Arrangement of elements based on recurring properties.
Q Who proposed the modern periodic law?
Ans: Henry Moseley.
Q State modern periodic law.
Ans: Properties of elements are periodic functions of their atomic numbers.
Q What is a period in periodic table?
Ans: Horizontal row of elements.
Q What is a group in periodic table?
Ans: Vertical column of elements.
Q What is atomic radius?
Ans: Distance between nucleus and outermost shell.
Q What is ionic radius?
Ans: Radius of an ion.
Q Define ionisation enthalpy.
Ans: Energy required to remove an electron.
Q What is electron gain enthalpy?
Ans: Energy change when an electron is added.
Q What is electronegativity?
Ans: Tendency to attract electrons in a bond.
Q What is valency?
Ans: Combining capacity of an element.
Q What is shielding effect?
Ans: Reduction of nuclear attraction due to inner electrons.
Q What is effective nuclear charge?
Ans: Net positive charge experienced by valence electrons.
Q What is periodicity?
Ans: Repetition of properties at regular intervals.
Q What are noble gases?
Ans: Group 18 elements with stable configuration.
Q What are alkali metals?
Ans: Group 1 elements.
Q What are alkaline earth metals?
Ans: Group 2 elements.
Q What are halogens?
Ans: Group 17 elements.
Q What is metallic character?
Ans: Tendency to lose electrons.
Q What is non-metallic character?
Ans: Tendency to gain electrons.
Q How does atomic radius change across period?
Ans: Decreases.
Q How does atomic radius change down group?
Ans: Increases.
Q How does ionisation enthalpy change across period?
Ans: Increases.
Q How does ionisation enthalpy change down group?
Ans: Decreases.
Q What is diagonal relationship?
Ans: Similarity between diagonal elements.
Q What is anomalous behaviour?
Ans: Deviation from expected trend.
Q Which element shows maximum electronegativity?
Ans: Fluorine.
Q Which element has largest atomic radius?
Ans: Francium.
Q What is periodic trend?
Ans: Variation of properties across table.
Q What is electron affinity?
Ans: Same as electron gain enthalpy.
II. Multiple Choice Questions (MCQs)
Q Modern periodic law is based on:
(a) atomic mass
(b) atomic number
(c) density
(d) valency
Ans: (b)
Q Periods are:
(a) vertical
(b) horizontal
(c) diagonal
(d) circular
Ans: (b)
Q Groups are:
(a) horizontal
(b) vertical
(c) diagonal
(d) none
Ans: (b)
Q Atomic radius decreases across period due to:
(a) decrease in nuclear charge
(b) increase in nuclear charge
(c) shielding
(d) none
Ans: (b)
Q Ionisation enthalpy increases across period due to:
(a) low attraction
(b) high attraction
(c) shielding
(d) none
Ans: (b)
Q Alkali metals belong to:
(a) group 2
(b) group 1
(c) group 17
(d) group 18
Ans: (b)
Q Halogens belong to:
(a) group 1
(b) group 2
(c) group 17
(d) group 18
Ans: (c)
Q Noble gases belong to:
(a) group 1
(b) group 17
(c) group 18
(d) group 2
Ans: (c)
Q Electronegativity increases across:
(a) group
(b) period
(c) both
(d) none
Ans: (b)
Q Metallic character decreases across:
(a) group
(b) period
(c) both
(d) none
Ans: (b)
Q Non-metallic character increases across:
(a) period
(b) group
(c) none
(d) both
Ans: (a)
Q Largest atomic size is:
(a) F
(b) Na
(c) Cs
(d) Cl
Ans: (c)
Q Highest electronegativity is:
(a) O
(b) F
(c) Cl
(d) N
Ans: (b)
Q Shielding effect is due to:
(a) nucleus
(b) electrons
(c) protons
(d) neutrons
Ans: (b)
Q Effective nuclear charge increases across:
(a) group
(b) period
(c) none
(d) both
Ans: (b)
Q Ionisation enthalpy decreases down group due to:
(a) size increase
(b) size decrease
(c) charge increase
(d) none
Ans: (a)
Q Diagonal relationship seen between:
(a) Li and Mg
(b) Na and K
(c) Cl and Br
(d) He and Ne
Ans: (a)
Q Electron affinity is:
(a) always positive
(b) always negative
(c) energy released/gained
(d) none
Ans: (c)
Q Smallest atom is:
(a) H
(b) He
(c) F
(d) O
Ans: (b)
Q Valency depends on:
(a) neutrons
(b) electrons
(c) protons
(d) mass
Ans: (b)
Q Metals tend to:
(a) gain electrons
(b) lose electrons
(c) share electrons
(d) none
Ans: (b)
Q Non-metals tend to:
(a) lose electrons
(b) gain electrons
(c) none
(d) both
Ans: (b)
Q Periodicity is due to:
(a) repetition of configuration
(b) mass
(c) density
(d) none
Ans: (a)
Q Maximum ionisation enthalpy is of:
(a) alkali metals
(b) noble gases
(c) halogens
(d) alkaline earth
Ans: (b)
Q Minimum ionisation enthalpy is of:
(a) alkali metals
(b) noble gases
(c) halogens
(d) none
Ans: (a)
Q Atomic size increases down group due to:
(a) more shells
(b) less shells
(c) less electrons
(d) none
Ans: (a)
Q Most reactive metal is:
(a) Li
(b) Na
(c) K
(d) Cs
Ans: (d)
Q Most reactive non-metal is:
(a) Cl
(b) F
(c) O
(d) N
Ans: (b)
Q Electronegativity decreases down group due to:
(a) size increase
(b) size decrease
(c) charge increase
(d) none
Ans: (a)
Q Assertion: Atomic radius decreases across a period.
Reason: Nuclear charge increases across a period.
(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)
Q Assertion: Ionisation enthalpy decreases down a group.
Reason: Atomic size increases down a group.
(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)
Q Assertion: Electronegativity increases across a period.
Reason: Effective nuclear charge increases.
(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)
Q Assertion: Noble gases are least reactive.
Reason: They have completely filled valence shells.
(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)
Q Assertion: Metallic character decreases across a period.
Reason: Tendency to lose electrons decreases.
(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)
Q Assertion: Electron affinity becomes more negative across period.
Reason: Nuclear attraction increases.
(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)
Q Assertion: Alkali metals are highly reactive.
Reason: They 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)
