Part I - NCERT

1 ChemistryPart ITextbook for Class XI2022-232 CHEMISTRY Publication TeamHead, Publication:Anup Kumar RajputDivisionChief Editor:Shveta UppalChief Production:Arun ChitkaraOfficerChief Business:Vipin DewanManagerEditor:Binoy BanerjeeProduction Officer:A. M. Vinod Kumar CoverShweta RaoIllustrationsNidhi WadhwaAnil NayalFirst EditionMarch 2006 Phalguna 1927 ReprintedOctober 2006 Kartika 1928 November 2007 Kartika 1929 January 2009 Magha 1930 December 2009 Pausa 1931 November 2010 Kartika 1932 January 2012 Pausha 1933 November 2012 Kartika 1934 November 2013 Kartika 1935 December 2014 Pausa 1936 May 2016 Vaishakha 1938 January 2018 Magha 1939 December 2018 Agrahayana 1940 October 2019 Ashwina 1941 July 2021 Asadha 1943 November 2021 Agrahayana 1943PD 340T RSP National Council of EducationalResearch and Training.

2 2006 on 80 GSM paper with NCERT watermarkPublished at the Publication Division by theSecretary, National Council of EducationalResearch and Training, Sri Aurobindo Marg,New Delhi 110 016 and printed at PankajPrinting Press, D-28, Industrial Area, Site-A,Mathura - 281 001 (Uttar Pradesh)11082 CHEMISTRY PART ITextbook for Class XIISBN 81-7450-494-X (Part I) 81-7450-535-0 (Part II)2022-233 ANSWERSFOREWORDThe National Curriculum Framework (NCF), 2005 recommends that children s life atschool must be linked to their life outside the school. This principle marks a departurefrom the legacy of bookish learning which continues to shape our system and causes agap between the school, home and community.

3 The syllabi and textbooks developed onthe basis of NCF signify an attempt to implement this basic idea. They also attempt todiscourage rote learning and the maintenance of sharp boundaries between differentsubject areas. We hope these measures will take us significantly further in the direction ofa child-centred system of education outlined in the National Policy on Education (1986).The success of this effort depends on the steps that school principals and teacherswill take to encourage children to reflect on their own learning and to pursueimaginative activities and questions. We must recognise that, given space, time andfreedom, children generate new knowledge by engaging with the information passedon to them by adults.

4 Treating the prescribed textbook as the sole basis of examinationis one of the key reasons why other resources and sites of learning are creativity and initiative is possible if we perceive and treat children asparticipants in learning, not as receivers of a fixed body of aims imply considerable change in school routines and mode of in the daily time-table is as necessary as rigour in implementing the annualcalender so that the required number of teaching days are actually devoted to methods used for teaching and evaluation will also determine how effective thistextbook proves for making children s life at school a happy experience, rather than asource of stress or boredom.

5 Syllabus designers have tried to address the problem ofcurricular burden by restructuring and reorienting knowledge at different stageswith greater consideration for child psychology and the time available for textbook attempts to enhance this endeavour by giving higher priority and spaceto opportunities for contemplation and wondering, discussion in small groups, andactivities requiring hands-on National Council of Educational Research and Training ( NCERT ) appreciatesthe hard work done by the textbook development committee responsible for this wish to thank the Chairperson of the advisory group in science and mathematics,Professor Narlikar and the Chief Advisor for this book, Professor B.

6 L. Khandelwalfor guiding the work of this committee. Several teachers contributed to the developmentof this textbook; we are grateful to their principals for making this possible. We areindebted to the institutions and organisations which have generously permitted us todraw upon their resources, material and personnel. As an organisation committed tosystemic reform and continuous improvement in the quality of its products, NCERT welcomes comments and suggestions which will enable us to undertake furtherrevision and DelhiNational Council of Educational20 December 2005 Research and Training2022-234 CHEMISTRY2022-235 ANSWERSTEXTBOOK DEVELOPMENT COMMITTEECHAIRPERSON, ADVISORY GROUP FOR TEXTBOOKS IN SCIENCE AND Narlikar, Emeritus Professor, Chairman, Advisory Committee, InterUniversity Centre for Astronomy and Astrophysics (IUCCA), Ganeshbhind,Pune university , PuneCHIEF Khandelwal, Professor (Retd.)

7 , Emeritus Scientist, CSIR; Emeritus Fellow, AICTEand formerly Chairman, Department of Chemistry, Indian Institute of Technology,New DelhiMEMBERSA. S. Brar, Professor, Indian Institute of Technology, DelhiAnjni Koul, Lecturer, DESM, NCERT , New Gupta, Professor, DESM, NCERT , New Aggarwal, Professor, Regional Institute of Education, BhopalJaishree Sharma, Professor, DESM, NCERT , New DelhiM. Chandra, Professor, DESM, NCERT , New DelhiPoonam Sawhney, PGT (Chemistry), Kendriya Vidyalaya, Vikas Puri, New Parashar, Lecturer, DESM, NCERT , New Dogra, Professor, Dr. Ambedkar Centre for Biomedical Research, university ofDelhi, Gupta, Reader, School of Studies in Chemistry, Jiwaji university , GwaliorSadhna Bhargava, PGT (Chemistry), Sardar Patel Vidyalaya, Lodhi Estate, New DelhiShubha Keshwan, Headmistress, Demonstration School, Regional Institute of Education,MysuruSukhvir Singh, Reader, DESM, NCERT , New DelhiSunita Malhotra, Professor, School of Sciences, IGNOU, Maidan Garhi, New Verma, Professor (Retd.)

8 , Institute of Technology, banaras hindu university , Gupta, Reader, Regional Institute of Education, BhopalMEMBER-COORDINATORAlka Mehrotra, Reader, DESM, NCERT , New Delhi2022-236 CHEMISTRYACKNOWLEDGEMENTSThe National Council of Educational Research and Training acknowledges the valuablecontributions of the individuals and organisations involved in the development ofChemistry textbook for Class XI. It also acknowledges that some useful material fromthe reprint editions (2005) of Chemistry textbooks has been utilised in the developmentof the present following academics contributed effectively in editing, reviewing, refining andfinalisation of the manuscript of this book: Bhandage, Professor, RIE, Mysuru;N.

9 Ram, Professor, IIT, New Delhi; Sanjeev Kumar, Associate Professor, School ofScience, IGNOU, Maidan Garhi, New Delhi; Shampa Bhattacharya, AssociateProfessor, Hans Raj College, Delhi; Vijay Sarda, Associate Professor (Retd.), ZakirHusain College, New Delhi; Arora, Associate Professor, Zakir Husain College,New Delhi; Shashi Saxena, Associate Professor, Hans Raj College, Delhi; AnuradhaSen, Apeejay School, Sheikh Sarai, New Delhi; C. Shrinivas, PGT, Kendriya Vidyalaya,Pushp Vihar, New Delhi; Bharti, PGT, Ramjas School, Sector IV, Puram, NewDelhi; Ila Sharma, PGT, Delhi Public School, Dwarka, Sector-B, New Delhi; Raj LakshmiKarthikeyan, Head (Science), Mother s International School, Sri Aurobindo Marg, NewDelhi; Sushma Kiran Setia, Principal, Sarvodaya Kanya Vidyalaya, Hari Nagar (CT),New Delhi; Nidhi Chaudray, PGT, CRPF Public School, Rohini, Delhi; and Veena Suri,PGT, Bluebells School, Kailash Colony, New Delhi.

10 We are thankful to express our gratitude to Sindhu, Professor (Retd.), DESM, NCERT , NewDelhi, for editing and refining the content of the textbook right from the initial are also grateful to Ruchi Verma, Associate Professor, DESM, NCERT , NewDelhi; Pramila Tanwar, Assistant Professor, DESM, NCERT , New Delhi; Pareek,Associate Professor, RIE, Ajmer; and Arya, Associate Professor, RIE, Ajmer, forrefining the content of the thanks are due to M. Chandra, Professor and Head (Retd.), DESM, NCERTfor her Council also gratefully acknowledges the contributions of Surendra Kumar,Narender Verma and Ramesh Kumar, DTP Operators; Subhash Saluja, RamendraKumar Sharma and Abhimanyu Mohanty, Proofreaders; Bhavna Saxena, CopyEditor; and Deepak Kapoor, In-charge, Computer Station, in shaping this book.