Class 10 Chemistry Chapter 1
Periodic Properties and Variations of Properties Important Questions

Here, you'll discover significant inquiries pertaining to Class 10 Periodic Properties and variations of Properties. These inquiries are carefully designed to aid students in preparing for the ICSE Class 10 Chemistry Examination in 2023–24. Engaging with different question formats allows students to address uncertainties, improve their exam preparedness, boost their self-assurance, and polish their ability to solve problems.

Introduction

In the first chapter of ICSE Class 10 Chemistry, Periodic Properties and variations of Properties, you will delve into fundamental principles such as Periodic Characteristics and their Variations within Groups and Periods. It is essential to study the definitions and patterns of the following periodic properties within both groups and periods: atomic size, metallic nature, non-metallic nature, ionisation potential, electron affinity, electronegativity, Periodicity based on Atomic Number for Elements. For those seeking "chemistry important questions class 10 ICSE," this chapter will provide a strong foundation. The examination will cover the exploration of the modern periodic table up to period 3, although students will be exposed to the complete modern periodic table. No questions will be posed regarding elements beyond period 3 (up to Argon). The explanations regarding Periodicity and other associated properties will be grounded in considerations of nuclear charge and electron shells, rather than orbitals. If you are looking for "ICSE class 10 chemistry important questions," this chapter will prepare you with the necessary knowledge.

What are Periodic Properties and Variations of Properties?

In ICSE Class 10 Chemistry Chapter 1, titled "Periodic Properties and Variations of Properties," elements found in the same groups, which are the vertical columns of the periodic table, demonstrate similar chemical characteristics. This uniformity is a result of group members having identical numbers and arrangements of electrons in their outermost electron shells. However, there are additional recurring patterns in chemical properties observed across the periodic table, including chemistry important questions class 10 ICSE.
‍For instance, as one moves down a group, the metallic properties of atoms become more pronounced. To illustrate, in the uppermost position of group 16 (6A), oxygen exists as a colourless gas. In the middle of the group, selenium takes the form of a semi-conductive solid. Meanwhile, towards the lower end of the group, polonium appears as a silver-grey solid with electrical conductivity. These observations are essential when preparing for ICSE Class 10 Chemistry important questions.
Conversely, when traversing a period from left to right, each successive element involves the addition of a proton to the nucleus and an electron to the valence shell. In contrast, while moving down a group, the count of electrons within the valence shell remains constant, but the principal quantum number increases by one with each step.
Understanding the electronic configuration of elements empowers us to analyse specific properties that dictate their chemical behaviour. These properties exhibit periodic variations as the electronic configuration of elements changes. These properties encompass factors such as the size (radius) of atoms and ions, ionisation energies, and (3) electron affinities. These concepts are crucial when studying ICSE Class 10 chemistry important questions.

Class 10 Chemistry Chapter 1 Periodic Properties and Variations of Properties Important Questions and Answers

Q1. Why is the magnesium atom smaller than the sodium atom?

Options

(a) Because the electrons in magnesium are contained in three shells.
(b) Because the electron shells are pulled inward more strongly in the Mg atom than in Na atom.
(c)Because the electron shells are pulled inward more strongly in Na atoms than in Mg atoms.
(d) None of the above

Ans. (a) Because the electrons in magnesium are contained in three shells.

Explanation:
Magnesium comes after sodium in the same period. Atoms of both elements have three electron shells (Na : 2, 8, 1 : Mg : 2, 8, 2). But the nuclear charge of sodium is + 11 and that of magnesium is + 12. Hence, the electron shells are pulled inward more strongly in the Mg atom than in Na atom. Hence, the Mg atom is smaller than Na atom.

Q2. The elements having the least number of electrons shells:

Options

(a) F
(b) K
(c) Na
(d) Li

Ans. (d) Li
Explanation:
Lithium has the least number of electron shells. This is because of its position in the periodic table, which is higher than sodium and potassium.

Q3. How many elements are in the third period of the modern periodic table? Write the names of first and last elements of the third period.

Explanation:
The third period of the periodic table contains eight elements. The first and last elements of the third phase are sodium (Na) and argon (Ar), respectively.

Q4. What are typical elements? Give the ‘liquid elements’ in the periodic table.

Explanation:
All the elements are found in the third short period of the Periodic Table: Na, Mg, Al, Si, P, S, Cl, and Ar. These components are referred to as typical elements . Liquid elements include bromine, mercury, and francium.

Q5. State Newland’s law of octaves. Why did the law of octaves fail? Write three important drawbacks of Newland’s classification.

Explanation:
According to Newland's Law of Octaves, an element with a similar property follows every seven elements. similar to how a musical node is repeated inside an octave.The following factors contributed to the law's failure:i The law was only valid up until calcium. Beyond calcium, the other elements could not be included.ii The ninth element, not the eighth, was found to have identical chemical properties with the discovery of rare gases.
‍
Drawbacks:
‍i Elements could not fit inside the table, according to Newland.
ii Inaccurate estimates of atomic weights were made.
iii Some elements didn't go with the approach.

ICSE Class 10 Chemistry Chapter wise Important Questions

Conclusion

The exploration of "Periodic Properties and Variations of Properties" in ICSE Class 10 Chemistry has illuminated the fundamental principles governing the behaviour of elements on the periodic table. The recognition of periodic trends, such as the variations in atomic size, ionisation energies, and electron affinities, provides invaluable insights into the properties and reactivity of these elements.As we delve into the intricacies of electronic configurations and examine the periodic patterns that emerge, we uncover a deeper understanding of the chemical world. Oswal.io offers an extensive collection of questions and study materials specifically designed to enhance your learning experience. These resources provide essential opportunities to test your comprehension, refine your skills, and strengthen your grasp of the concepts covered in this chapter.

Frequently Asked Questions

Q1 : State modern periodic law.

Ans: The properties of elements are periodic functions of their atomic number," according to the modern periodic law.

Q2: Name the scientist who stated the law.

Ans:  The periodic law was proposed by Henry Moseley.

Q3 : How many groups and periods does the modern periodic table have?

Ans: Modern Periodic table has 7 periods and 18 groups.

Q4 : What are horizontal rows and vertical columns in a periodic table known as?

Ans:  In the periodic table, the horizontal rows are known as periods, while the vertical columns are known as groups.

Q5 : Name 2 elements you would expect to show chemical reactions similar to calcium. What is the basis of your choice?

Ans: Beryllium and magnesium will have chemical interactions that are similar to those of calcium. Because these elements, like calcium, belong to the same group 2 and have two electrons in their outermost shell.