Periodic Properties | तत्वों के आवर्ती गुण | Chemistry | 11th | Chapter 3 | Part 03 | Vikram Sir

Read the passage given below and answer the following questions: The d block elements are the 40 elements contained in the four rows of ten columns (3-12) in the periodic table. As all the d block elements are metallic, the term d-block metals is synonymous. This set of d-block elements is also often identified as the transition metals, but sometimes the group 12 elements (zinc, cadmium, mercury) are excluded from the transition metals as the transition elements are defined as those with partly filled d or fshells in their compounds. Inclusion of the elements zinc, cadmium and mercury is necessary as some properties of the group 12 elements are appropriate logically to include with a discussion of transition metal chemistry. The term transition element or transition metal appeared to derive from early studies of periodicity such as the Mendeleev periodic table of the elements. His horizontal table of the elements was an attempt to group the elements together so that the chemistry of elements might be explained and predicted. In this table there are eight groups labeled I-VIII with each subdivided into A and B subgroups. Mendeleev recognize properties of elements in Group VII are related those of some of the elements in Group VII and those at the start of the next row Group I. In that sense, these elements might be described as possessing properties transitional from one row of the table to the next. Assertion (A): Group VII elements of Mendeleev periodic table are transition elements. Reason (R): Group I -VIII in Mendeleev periodic table is divided into two subgroups, A and B.

A and B are partners in a firm shaing profits in the ratio of 3 : 2. They admit C as a partner on 1st April, 2019 on which date the Balance Sheet of the firm was: You are required to parpare the Revaluation Account, Partners' Capital Accounts and Balance Sheet of the new firm after considering the following: (a) C brings RS.30,000 as Capital for 1/4th share. He also brings RS.10,000 for his for share of goodwill. (b) Part of the Stock which had been included at cost of RS.2,000 had been badly damaged in storage and could only expect to realise RS.400. (c) Bank changes had been overlooked and amounted to RS.200 for the year 2018-19. (d) Depreciation on Building of RS.3,000 had been omitted for the year 2018-19. (e) A credit for goods for RS.800 had been omitted from both purchases and creditors although the goods had been correctly included in Stock. (f) An expense of RS.1,200 for insurance premium was debited in the Profit and Loss Account of 2018-19 but RS.600 of this are related to the period after 31st March, 2019.

Class 12 Chemistry | Chapter 11 Alcohol, Phenol and Ethers | Important Questions and Quick Revision| Part 1

Class 12 Chemistry | Chapter 11 Alcohol, Phenol and Ethers | Important Questions and Quick Revision| Part 2

Read the passage given below and answer the following questions: The d block elements are the 40 elements contained in the four rows of ten columns (3-12) in the periodic table. As all the d block elements are metallic, the term d-block metals is synonymous. This set of d-block elements is also often identified as the transition metals, but sometimes the group 12 elements (zinc, cadmium, mercury) are excluded from the transition metals as the transition elements are defined as those with partly filled d or fshells in their compounds. Inclusion of the elements zinc, cadmium and mercury is necessary as some properties of the group 12 elements are appropriate logically to include with a discussion of transition metal chemistry. The term transition element or transition metal appeared to derive from early studies of periodicity such as the Mendeleev periodic table of the elements. His horizontal table of the elements was an attempt to group the elements together so that the chemistry of elements might be explained and predicted. In this table there are eight groups labeled I-VIII with each subdivided into A and B subgroups. Mendeleev recognize properties of elements in Group VII are related those of some of the elements in Group VII and those at the start of the next row Group I. In that sense, these elements might be described as possessing properties transitional from one row of the table to the next. Assertion (A): Nickel is a transition element that belongs to group 10 and period 4 of the modern periodic table. Reason (R): Electronic configuration of Nickel is [Ar]_(18)3d^(8)4s^2

The ratio of the efficiencies of A, B and C is 2 : 5 : 3. Working together, they can complete a work in 27 days. B and C together can complete 4/9th part of that work in: A, B और C की कार्य क्षमता का अनुपात 2 : 5 : 3 है | एक साथ कार्य करते हुए, वे किसी कार्य को 27 दिन में पूरा कर सकते हैं | B और C एक साथ उस कार्य के 4/9 भाग को कितने दिनों में पूरा करेंगे ?