Class 10 Science: Question Paper for 2018 | Science Class 10 PDF Download

 Page 1


31/1 1 [P.T.O. 
 
 
 
 
 
???? ??.  
Roll No.  
 
  
 
?????
SCIENCE 
 
???????? ???  :  3 ???? ?????? ??? :  80 
Time allowed : 3 hours Maximum Marks : 80 
 Series : TYM 
31/1
H$moS> Z§. 
Code No.  
??????? ???? ??? ???-??????? ?? ???-???? 
?? ???? ???? ? 
Candidates must write the Code on 
the title page of the answer-book. 
SET – 1 
? ????? ???? ?? ?? ?? ?? ???-?? ?? ????? ???? 12 ?? ? 
? ???-?? ?? ?????? ??? ?? ???? ??? ?? ???? ???? ??? ??? ???-??????? ?? ???-???? ?? ???? ? 
? ????? ???? ?? ?? ?? ?? ???-?? ?? 27 ??? ?? ? 
? ????? ??? ?? ??? ????? ??? ???? ?? ????, ??? ?? ????? ???? ???? ? 
? ?? ???-?? ??? ???? ?? ??? 15 ???? ?? ??? ???? ??? ?? ? ???-?? ?? ????? ?????? ?? 10.15 ??? 
???? ????? ? 10.15 ??? ?? 10.30 ??? ?? ??? ???? ???-?? ??? ????? ???? ?? ???? ?? ?????? ?? 
???-??????? ?? ????? ??? ??? ?????? ? 
? Please check that this question paper contains 12 printed pages. 
? Code number given on the right hand side of the question paper should be written on the 
title page of the answer-book by the candidate. 
? Please check that this question paper contains 27 questions. 
? Please write down the Serial Number of the question before attempting it. 
? 15 minute time has been allotted to read this question paper. The question paper will be 
distributed at 10.15 a.m. From 10.15 a.m. to 10.30 a.m., the students will read the 
question paper only and will not write any answer on the answer-book during this period. 
Page 2


31/1 1 [P.T.O. 
 
 
 
 
 
???? ??.  
Roll No.  
 
  
 
?????
SCIENCE 
 
???????? ???  :  3 ???? ?????? ??? :  80 
Time allowed : 3 hours Maximum Marks : 80 
 Series : TYM 
31/1
H$moS> Z§. 
Code No.  
??????? ???? ??? ???-??????? ?? ???-???? 
?? ???? ???? ? 
Candidates must write the Code on 
the title page of the answer-book. 
SET – 1 
? ????? ???? ?? ?? ?? ?? ???-?? ?? ????? ???? 12 ?? ? 
? ???-?? ?? ?????? ??? ?? ???? ??? ?? ???? ???? ??? ??? ???-??????? ?? ???-???? ?? ???? ? 
? ????? ???? ?? ?? ?? ?? ???-?? ?? 27 ??? ?? ? 
? ????? ??? ?? ??? ????? ??? ???? ?? ????, ??? ?? ????? ???? ???? ? 
? ?? ???-?? ??? ???? ?? ??? 15 ???? ?? ??? ???? ??? ?? ? ???-?? ?? ????? ?????? ?? 10.15 ??? 
???? ????? ? 10.15 ??? ?? 10.30 ??? ?? ??? ???? ???-?? ??? ????? ???? ?? ???? ?? ?????? ?? 
???-??????? ?? ????? ??? ??? ?????? ? 
? Please check that this question paper contains 12 printed pages. 
? Code number given on the right hand side of the question paper should be written on the 
title page of the answer-book by the candidate. 
? Please check that this question paper contains 27 questions. 
? Please write down the Serial Number of the question before attempting it. 
? 15 minute time has been allotted to read this question paper. The question paper will be 
distributed at 10.15 a.m. From 10.15 a.m. to 10.30 a.m., the students will read the 
question paper only and will not write any answer on the answer-book during this period. 
31/1 2   
?????? ????? : 
 (i) ?? ???-?? ??? ??? ?????, ??? ? ???? ??? ?, ?? ????? ??? ?? ? ?????? ?????? ????? ?? ????? ?? ??? 
????? ?? ?
 (ii) ??? ??? ??????? ?? ? 
 (iii) ??????  ??? ? ???? ??? ? ?? ??? ????? ?? ??? ?????-????? ??? ?? ????? ?? ????? ?? ?
(iv) ???? ??? ? ?? ??? ??? ?? ??? ?????, ???? ??? ?? ??? ????? ???? ??? ? ?? ??? ??? ?? ?? ??? ?? 
??????? ??? ???? ??? ?? ? 
(v) ??? ? ?? ??? ????? 1 ???? 2 ??-?? ??? ?? ??? ?? ? ???? ??? ?? ??? ???? ?? ???? ?? 
????? ? 
 (vi) ??? ? ?? ??? ????? 3 ?? 5 ???-??? ????? ?? ??? ?? ? ???? ??? ????  30 ????? ?? ???? ?? ? 
 (vii) ??? ? ?? ??? ????? 6 ?? 15 ???-??? ????? ?? ??? ?? ? ???? ??? ???? 50 ????? ?? ???? ?? ? 
 (viii) ??? ? ?? ??? ????? 16 ?? 21 ????-???? ????? ?? ??? ?? ? ???? ??? ???? 70 ????? ?? ???? ?? ? 
 (ix)  ??? ? ?? ??? ????? 22 ?? 27 ????????? ????? ?? ??????? ???-??? ????? ?? ??? ?? ? ???? ??? 
????? ?? ???? ?? ?  
General Instructions :   
 (i) The question paper comprises two Sections, A and B. You are to attempt both the 
sections.  
 (ii) All questions are compulsory. 
 (iii) All questions of Section A and Section B are to be attempted separately. 
 (iv) There is an internal choice in three questions of three marks each, two questions of 
five marks each in Section A and in one question of two marks in Section B. 
 (v) Question numbers 1 and 2 in Section A are one-mark questions. They are to be 
answered in one word or in one sentence. 
 (vi) Question numbers 3 to 5 in Section A are two-marks questions. These are to be 
answered in about 30 words each. 
 (vii) Question numbers 6 to 15 in Section A are three-marks questions. These are to be 
answered in about 50 words each. 
 (viii) Question numbers 16 to 21 in Section A are five-marks questions. These are to be 
answered in about 70 words each. 
 (ix) Question numbers 22 to 27 in Section B are based on practical skills. Each 
question is a two-marks question. These are to be answered in brief.  
Page 3


31/1 1 [P.T.O. 
 
 
 
 
 
???? ??.  
Roll No.  
 
  
 
?????
SCIENCE 
 
???????? ???  :  3 ???? ?????? ??? :  80 
Time allowed : 3 hours Maximum Marks : 80 
 Series : TYM 
31/1
H$moS> Z§. 
Code No.  
??????? ???? ??? ???-??????? ?? ???-???? 
?? ???? ???? ? 
Candidates must write the Code on 
the title page of the answer-book. 
SET – 1 
? ????? ???? ?? ?? ?? ?? ???-?? ?? ????? ???? 12 ?? ? 
? ???-?? ?? ?????? ??? ?? ???? ??? ?? ???? ???? ??? ??? ???-??????? ?? ???-???? ?? ???? ? 
? ????? ???? ?? ?? ?? ?? ???-?? ?? 27 ??? ?? ? 
? ????? ??? ?? ??? ????? ??? ???? ?? ????, ??? ?? ????? ???? ???? ? 
? ?? ???-?? ??? ???? ?? ??? 15 ???? ?? ??? ???? ??? ?? ? ???-?? ?? ????? ?????? ?? 10.15 ??? 
???? ????? ? 10.15 ??? ?? 10.30 ??? ?? ??? ???? ???-?? ??? ????? ???? ?? ???? ?? ?????? ?? 
???-??????? ?? ????? ??? ??? ?????? ? 
? Please check that this question paper contains 12 printed pages. 
? Code number given on the right hand side of the question paper should be written on the 
title page of the answer-book by the candidate. 
? Please check that this question paper contains 27 questions. 
? Please write down the Serial Number of the question before attempting it. 
? 15 minute time has been allotted to read this question paper. The question paper will be 
distributed at 10.15 a.m. From 10.15 a.m. to 10.30 a.m., the students will read the 
question paper only and will not write any answer on the answer-book during this period. 
31/1 2   
?????? ????? : 
 (i) ?? ???-?? ??? ??? ?????, ??? ? ???? ??? ?, ?? ????? ??? ?? ? ?????? ?????? ????? ?? ????? ?? ??? 
????? ?? ?
 (ii) ??? ??? ??????? ?? ? 
 (iii) ??????  ??? ? ???? ??? ? ?? ??? ????? ?? ??? ?????-????? ??? ?? ????? ?? ????? ?? ?
(iv) ???? ??? ? ?? ??? ??? ?? ??? ?????, ???? ??? ?? ??? ????? ???? ??? ? ?? ??? ??? ?? ?? ??? ?? 
??????? ??? ???? ??? ?? ? 
(v) ??? ? ?? ??? ????? 1 ???? 2 ??-?? ??? ?? ??? ?? ? ???? ??? ?? ??? ???? ?? ???? ?? 
????? ? 
 (vi) ??? ? ?? ??? ????? 3 ?? 5 ???-??? ????? ?? ??? ?? ? ???? ??? ????  30 ????? ?? ???? ?? ? 
 (vii) ??? ? ?? ??? ????? 6 ?? 15 ???-??? ????? ?? ??? ?? ? ???? ??? ???? 50 ????? ?? ???? ?? ? 
 (viii) ??? ? ?? ??? ????? 16 ?? 21 ????-???? ????? ?? ??? ?? ? ???? ??? ???? 70 ????? ?? ???? ?? ? 
 (ix)  ??? ? ?? ??? ????? 22 ?? 27 ????????? ????? ?? ??????? ???-??? ????? ?? ??? ?? ? ???? ??? 
????? ?? ???? ?? ?  
General Instructions :   
 (i) The question paper comprises two Sections, A and B. You are to attempt both the 
sections.  
 (ii) All questions are compulsory. 
 (iii) All questions of Section A and Section B are to be attempted separately. 
 (iv) There is an internal choice in three questions of three marks each, two questions of 
five marks each in Section A and in one question of two marks in Section B. 
 (v) Question numbers 1 and 2 in Section A are one-mark questions. They are to be 
answered in one word or in one sentence. 
 (vi) Question numbers 3 to 5 in Section A are two-marks questions. These are to be 
answered in about 30 words each. 
 (vii) Question numbers 6 to 15 in Section A are three-marks questions. These are to be 
answered in about 50 words each. 
 (viii) Question numbers 16 to 21 in Section A are five-marks questions. These are to be 
answered in about 70 words each. 
 (ix) Question numbers 22 to 27 in Section B are based on practical skills. Each 
question is a two-marks question. These are to be answered in brief.  
31/1 3 [P.T.O. 
??? – ?  
Section – A 
 
1. ???? ?? ?? ????? ?? ????? ??? ?? ?????? ???? ??? ?? ?????? ?? ????? ???? ????? ???? ??? ?? ?????? ?? 
????? ??? ? F
1
 ????? ?? ??? ?????? ???? ????? ? 1 
A Mendelian experiment consisted of breeding pea plants bearing violet flowers with 
pea plants bearing white flowers. What will be the result in F
1
 progeny ?  
 
2. ?? ????? ????? ?? ????? ???? ????-??????? ????? ? 1  
 Write the energy conversion that takes place in a hydropower plant.  
 
3. ????? ?????? ‘X’ ?????? ???? ???????? ??? ?? ??? 443 K ?? ??? ???? ?? ????? ??????? ?????? 
‘Y’ ????? ?? ? ?????? ‘X’ ??????? ???? ?? ?? ??????? ???? ?? ????? ????? ?????? ??? ‘Z’ 
?????? ?? ? ‘X’, ‘Y’ ??? ‘Z’ ??? ??????? ? ‘Y’ ????? ????? ?? ???????? ??????? ?? 
?????? ?? ????? ??? ???? ???? ???????? ??? ?? ?????? ?? ????? ?? ????? ? 2 
 A compound ‘X’ on heating with excess conc. sulphuric acid at 443 K gives an 
unsaturated compound ‘Y’. ‘X’ also reacts with sodium metal to evolve a colourless 
gas ‘Z’. Identify ‘X’, ‘Y’ and ‘Z’. Write the equation of the chemical reaction of 
formation of ‘Y’ and also write the role of sulphuric acid in the reaction.    
 
4. (a) ?????? ?? ??? ???? ???? ?? ?? ?????? ???? ??? ?? ??????? ?? ??? ????? ? 2 
 (b) ???? ??? ?? ??????? ?? ???? ?????, ????? ????? ????? ????? ?? ?? ?? ??? ???? ??, ??? 
???? ??? ??????? ?? ????? ???? a ???? b ?? ??? ????? ? 
?????? ?? 
a 
?? 
b 
?? ?????? ?? ????? ???? 
 (a) Name one gustatory receptor and one olfactory receptor present in human beings. 
 (b) Write a and b in the given flow chart of neuron through which information 
travels as an electrical impulse. 
Dendrite ?? 
a 
?? 
b 
?? 
End point of Neuron 
 
Page 4


31/1 1 [P.T.O. 
 
 
 
 
 
???? ??.  
Roll No.  
 
  
 
?????
SCIENCE 
 
???????? ???  :  3 ???? ?????? ??? :  80 
Time allowed : 3 hours Maximum Marks : 80 
 Series : TYM 
31/1
H$moS> Z§. 
Code No.  
??????? ???? ??? ???-??????? ?? ???-???? 
?? ???? ???? ? 
Candidates must write the Code on 
the title page of the answer-book. 
SET – 1 
? ????? ???? ?? ?? ?? ?? ???-?? ?? ????? ???? 12 ?? ? 
? ???-?? ?? ?????? ??? ?? ???? ??? ?? ???? ???? ??? ??? ???-??????? ?? ???-???? ?? ???? ? 
? ????? ???? ?? ?? ?? ?? ???-?? ?? 27 ??? ?? ? 
? ????? ??? ?? ??? ????? ??? ???? ?? ????, ??? ?? ????? ???? ???? ? 
? ?? ???-?? ??? ???? ?? ??? 15 ???? ?? ??? ???? ??? ?? ? ???-?? ?? ????? ?????? ?? 10.15 ??? 
???? ????? ? 10.15 ??? ?? 10.30 ??? ?? ??? ???? ???-?? ??? ????? ???? ?? ???? ?? ?????? ?? 
???-??????? ?? ????? ??? ??? ?????? ? 
? Please check that this question paper contains 12 printed pages. 
? Code number given on the right hand side of the question paper should be written on the 
title page of the answer-book by the candidate. 
? Please check that this question paper contains 27 questions. 
? Please write down the Serial Number of the question before attempting it. 
? 15 minute time has been allotted to read this question paper. The question paper will be 
distributed at 10.15 a.m. From 10.15 a.m. to 10.30 a.m., the students will read the 
question paper only and will not write any answer on the answer-book during this period. 
31/1 2   
?????? ????? : 
 (i) ?? ???-?? ??? ??? ?????, ??? ? ???? ??? ?, ?? ????? ??? ?? ? ?????? ?????? ????? ?? ????? ?? ??? 
????? ?? ?
 (ii) ??? ??? ??????? ?? ? 
 (iii) ??????  ??? ? ???? ??? ? ?? ??? ????? ?? ??? ?????-????? ??? ?? ????? ?? ????? ?? ?
(iv) ???? ??? ? ?? ??? ??? ?? ??? ?????, ???? ??? ?? ??? ????? ???? ??? ? ?? ??? ??? ?? ?? ??? ?? 
??????? ??? ???? ??? ?? ? 
(v) ??? ? ?? ??? ????? 1 ???? 2 ??-?? ??? ?? ??? ?? ? ???? ??? ?? ??? ???? ?? ???? ?? 
????? ? 
 (vi) ??? ? ?? ??? ????? 3 ?? 5 ???-??? ????? ?? ??? ?? ? ???? ??? ????  30 ????? ?? ???? ?? ? 
 (vii) ??? ? ?? ??? ????? 6 ?? 15 ???-??? ????? ?? ??? ?? ? ???? ??? ???? 50 ????? ?? ???? ?? ? 
 (viii) ??? ? ?? ??? ????? 16 ?? 21 ????-???? ????? ?? ??? ?? ? ???? ??? ???? 70 ????? ?? ???? ?? ? 
 (ix)  ??? ? ?? ??? ????? 22 ?? 27 ????????? ????? ?? ??????? ???-??? ????? ?? ??? ?? ? ???? ??? 
????? ?? ???? ?? ?  
General Instructions :   
 (i) The question paper comprises two Sections, A and B. You are to attempt both the 
sections.  
 (ii) All questions are compulsory. 
 (iii) All questions of Section A and Section B are to be attempted separately. 
 (iv) There is an internal choice in three questions of three marks each, two questions of 
five marks each in Section A and in one question of two marks in Section B. 
 (v) Question numbers 1 and 2 in Section A are one-mark questions. They are to be 
answered in one word or in one sentence. 
 (vi) Question numbers 3 to 5 in Section A are two-marks questions. These are to be 
answered in about 30 words each. 
 (vii) Question numbers 6 to 15 in Section A are three-marks questions. These are to be 
answered in about 50 words each. 
 (viii) Question numbers 16 to 21 in Section A are five-marks questions. These are to be 
answered in about 70 words each. 
 (ix) Question numbers 22 to 27 in Section B are based on practical skills. Each 
question is a two-marks question. These are to be answered in brief.  
31/1 3 [P.T.O. 
??? – ?  
Section – A 
 
1. ???? ?? ?? ????? ?? ????? ??? ?? ?????? ???? ??? ?? ?????? ?? ????? ???? ????? ???? ??? ?? ?????? ?? 
????? ??? ? F
1
 ????? ?? ??? ?????? ???? ????? ? 1 
A Mendelian experiment consisted of breeding pea plants bearing violet flowers with 
pea plants bearing white flowers. What will be the result in F
1
 progeny ?  
 
2. ?? ????? ????? ?? ????? ???? ????-??????? ????? ? 1  
 Write the energy conversion that takes place in a hydropower plant.  
 
3. ????? ?????? ‘X’ ?????? ???? ???????? ??? ?? ??? 443 K ?? ??? ???? ?? ????? ??????? ?????? 
‘Y’ ????? ?? ? ?????? ‘X’ ??????? ???? ?? ?? ??????? ???? ?? ????? ????? ?????? ??? ‘Z’ 
?????? ?? ? ‘X’, ‘Y’ ??? ‘Z’ ??? ??????? ? ‘Y’ ????? ????? ?? ???????? ??????? ?? 
?????? ?? ????? ??? ???? ???? ???????? ??? ?? ?????? ?? ????? ?? ????? ? 2 
 A compound ‘X’ on heating with excess conc. sulphuric acid at 443 K gives an 
unsaturated compound ‘Y’. ‘X’ also reacts with sodium metal to evolve a colourless 
gas ‘Z’. Identify ‘X’, ‘Y’ and ‘Z’. Write the equation of the chemical reaction of 
formation of ‘Y’ and also write the role of sulphuric acid in the reaction.    
 
4. (a) ?????? ?? ??? ???? ???? ?? ?? ?????? ???? ??? ?? ??????? ?? ??? ????? ? 2 
 (b) ???? ??? ?? ??????? ?? ???? ?????, ????? ????? ????? ????? ?? ?? ?? ??? ???? ??, ??? 
???? ??? ??????? ?? ????? ???? a ???? b ?? ??? ????? ? 
?????? ?? 
a 
?? 
b 
?? ?????? ?? ????? ???? 
 (a) Name one gustatory receptor and one olfactory receptor present in human beings. 
 (b) Write a and b in the given flow chart of neuron through which information 
travels as an electrical impulse. 
Dendrite ?? 
a 
?? 
b 
?? 
End point of Neuron 
 
31/1 4   
5. ??? ???? ?????? ???? ???? ???? ????? ??? ???? ?? ???? ?? ????? ?? ??? ???? ?? ???? ?? 
???? ???? ???? ?? ????? ??????? ???? ??, ??? ?? ???? ??? ???? ?? ?? ? ???? ??? ?? ????? ?? 
??? ???????? ???? ????? ????? ? 2 
 If the image formed by a spherical mirror for all positions of the object placed in front 
of it is always erect and diminished, what type of mirror is it ? Draw a labelled ray 
diagram to support your answer.     
 
6. ??????? (?????) ?????????? ?? ????????? ??? ?????? ?? ??? ?? ??? ???? ???? ???? ???? 
????? ???? ?? ???????? ????? ?? ? ????? ???? ?? ??????? ???????, ????? ????, ???? ???? 
????? ???? ?? ??????? ?? ???? ??, ?? ??? ??-?? ???????? ?????? ????? ? 3 
 Decomposition reactions require energy either in the form of heat or light or electricity 
for breaking down the reactants. Write one equation each for decomposition reactions 
where energy is supplied in the form of heat, light and electricity.   
 
7. ???? ?????? ?? ??????? ???? ?? ??? ????? ???? ????  2 mL ??????? ???????????? ?? ????? 
???? ??? ? ?????? ?? ????? ??? ??? ???? ?? ????? ??? ??????? ??? ????? ????? ???? ?? ???? 
??? ????? ?? ????? ?? ?????? ???? ??? ????? ??? ?? ??????? ??? ? ????? ???? ??????? ?? 
?????? ??? ?? ??? ?? ?????? ?? ??? ????? ????? ? ??? ??? ???? ???? ??? ??? ?? ??? 
????? ?? ??????? ???, ??? ??? ??? ??????? ????? ???? ??? ????? ?  3 
???? 
 ??????? ??? ??????? ???? ???? ????? ?? ??? ?????? ??? ???? ???? ???? ??? ?? pH ??? 14 ?? ? 
?? ??? ??? ??????? ??? ???? ?????? ?? ??? ???????? ?????? ????? ? ???? ??? ???????? ?? 
???? ????? ? 
 2 mL of sodium hydroxide solution is added to a few pieces of granulated zinc metal 
taken in a test tube. When the contents are warmed, a gas evolves which is bubbled 
through a soap solution before testing. Write the equation of the chemical reaction 
involved and the test to detect the gas. Name the gas which will be evolved when the 
same metal reacts with dilute solution of a strong acid.  
OR 
 The pH of a salt used to make tasty and crispy pakoras is 14. Identify the salt and 
write a chemical equation for its formation. List its two uses.   
Page 5


31/1 1 [P.T.O. 
 
 
 
 
 
???? ??.  
Roll No.  
 
  
 
?????
SCIENCE 
 
???????? ???  :  3 ???? ?????? ??? :  80 
Time allowed : 3 hours Maximum Marks : 80 
 Series : TYM 
31/1
H$moS> Z§. 
Code No.  
??????? ???? ??? ???-??????? ?? ???-???? 
?? ???? ???? ? 
Candidates must write the Code on 
the title page of the answer-book. 
SET – 1 
? ????? ???? ?? ?? ?? ?? ???-?? ?? ????? ???? 12 ?? ? 
? ???-?? ?? ?????? ??? ?? ???? ??? ?? ???? ???? ??? ??? ???-??????? ?? ???-???? ?? ???? ? 
? ????? ???? ?? ?? ?? ?? ???-?? ?? 27 ??? ?? ? 
? ????? ??? ?? ??? ????? ??? ???? ?? ????, ??? ?? ????? ???? ???? ? 
? ?? ???-?? ??? ???? ?? ??? 15 ???? ?? ??? ???? ??? ?? ? ???-?? ?? ????? ?????? ?? 10.15 ??? 
???? ????? ? 10.15 ??? ?? 10.30 ??? ?? ??? ???? ???-?? ??? ????? ???? ?? ???? ?? ?????? ?? 
???-??????? ?? ????? ??? ??? ?????? ? 
? Please check that this question paper contains 12 printed pages. 
? Code number given on the right hand side of the question paper should be written on the 
title page of the answer-book by the candidate. 
? Please check that this question paper contains 27 questions. 
? Please write down the Serial Number of the question before attempting it. 
? 15 minute time has been allotted to read this question paper. The question paper will be 
distributed at 10.15 a.m. From 10.15 a.m. to 10.30 a.m., the students will read the 
question paper only and will not write any answer on the answer-book during this period. 
31/1 2   
?????? ????? : 
 (i) ?? ???-?? ??? ??? ?????, ??? ? ???? ??? ?, ?? ????? ??? ?? ? ?????? ?????? ????? ?? ????? ?? ??? 
????? ?? ?
 (ii) ??? ??? ??????? ?? ? 
 (iii) ??????  ??? ? ???? ??? ? ?? ??? ????? ?? ??? ?????-????? ??? ?? ????? ?? ????? ?? ?
(iv) ???? ??? ? ?? ??? ??? ?? ??? ?????, ???? ??? ?? ??? ????? ???? ??? ? ?? ??? ??? ?? ?? ??? ?? 
??????? ??? ???? ??? ?? ? 
(v) ??? ? ?? ??? ????? 1 ???? 2 ??-?? ??? ?? ??? ?? ? ???? ??? ?? ??? ???? ?? ???? ?? 
????? ? 
 (vi) ??? ? ?? ??? ????? 3 ?? 5 ???-??? ????? ?? ??? ?? ? ???? ??? ????  30 ????? ?? ???? ?? ? 
 (vii) ??? ? ?? ??? ????? 6 ?? 15 ???-??? ????? ?? ??? ?? ? ???? ??? ???? 50 ????? ?? ???? ?? ? 
 (viii) ??? ? ?? ??? ????? 16 ?? 21 ????-???? ????? ?? ??? ?? ? ???? ??? ???? 70 ????? ?? ???? ?? ? 
 (ix)  ??? ? ?? ??? ????? 22 ?? 27 ????????? ????? ?? ??????? ???-??? ????? ?? ??? ?? ? ???? ??? 
????? ?? ???? ?? ?  
General Instructions :   
 (i) The question paper comprises two Sections, A and B. You are to attempt both the 
sections.  
 (ii) All questions are compulsory. 
 (iii) All questions of Section A and Section B are to be attempted separately. 
 (iv) There is an internal choice in three questions of three marks each, two questions of 
five marks each in Section A and in one question of two marks in Section B. 
 (v) Question numbers 1 and 2 in Section A are one-mark questions. They are to be 
answered in one word or in one sentence. 
 (vi) Question numbers 3 to 5 in Section A are two-marks questions. These are to be 
answered in about 30 words each. 
 (vii) Question numbers 6 to 15 in Section A are three-marks questions. These are to be 
answered in about 50 words each. 
 (viii) Question numbers 16 to 21 in Section A are five-marks questions. These are to be 
answered in about 70 words each. 
 (ix) Question numbers 22 to 27 in Section B are based on practical skills. Each 
question is a two-marks question. These are to be answered in brief.  
31/1 3 [P.T.O. 
??? – ?  
Section – A 
 
1. ???? ?? ?? ????? ?? ????? ??? ?? ?????? ???? ??? ?? ?????? ?? ????? ???? ????? ???? ??? ?? ?????? ?? 
????? ??? ? F
1
 ????? ?? ??? ?????? ???? ????? ? 1 
A Mendelian experiment consisted of breeding pea plants bearing violet flowers with 
pea plants bearing white flowers. What will be the result in F
1
 progeny ?  
 
2. ?? ????? ????? ?? ????? ???? ????-??????? ????? ? 1  
 Write the energy conversion that takes place in a hydropower plant.  
 
3. ????? ?????? ‘X’ ?????? ???? ???????? ??? ?? ??? 443 K ?? ??? ???? ?? ????? ??????? ?????? 
‘Y’ ????? ?? ? ?????? ‘X’ ??????? ???? ?? ?? ??????? ???? ?? ????? ????? ?????? ??? ‘Z’ 
?????? ?? ? ‘X’, ‘Y’ ??? ‘Z’ ??? ??????? ? ‘Y’ ????? ????? ?? ???????? ??????? ?? 
?????? ?? ????? ??? ???? ???? ???????? ??? ?? ?????? ?? ????? ?? ????? ? 2 
 A compound ‘X’ on heating with excess conc. sulphuric acid at 443 K gives an 
unsaturated compound ‘Y’. ‘X’ also reacts with sodium metal to evolve a colourless 
gas ‘Z’. Identify ‘X’, ‘Y’ and ‘Z’. Write the equation of the chemical reaction of 
formation of ‘Y’ and also write the role of sulphuric acid in the reaction.    
 
4. (a) ?????? ?? ??? ???? ???? ?? ?? ?????? ???? ??? ?? ??????? ?? ??? ????? ? 2 
 (b) ???? ??? ?? ??????? ?? ???? ?????, ????? ????? ????? ????? ?? ?? ?? ??? ???? ??, ??? 
???? ??? ??????? ?? ????? ???? a ???? b ?? ??? ????? ? 
?????? ?? 
a 
?? 
b 
?? ?????? ?? ????? ???? 
 (a) Name one gustatory receptor and one olfactory receptor present in human beings. 
 (b) Write a and b in the given flow chart of neuron through which information 
travels as an electrical impulse. 
Dendrite ?? 
a 
?? 
b 
?? 
End point of Neuron 
 
31/1 4   
5. ??? ???? ?????? ???? ???? ???? ????? ??? ???? ?? ???? ?? ????? ?? ??? ???? ?? ???? ?? 
???? ???? ???? ?? ????? ??????? ???? ??, ??? ?? ???? ??? ???? ?? ?? ? ???? ??? ?? ????? ?? 
??? ???????? ???? ????? ????? ? 2 
 If the image formed by a spherical mirror for all positions of the object placed in front 
of it is always erect and diminished, what type of mirror is it ? Draw a labelled ray 
diagram to support your answer.     
 
6. ??????? (?????) ?????????? ?? ????????? ??? ?????? ?? ??? ?? ??? ???? ???? ???? ???? 
????? ???? ?? ???????? ????? ?? ? ????? ???? ?? ??????? ???????, ????? ????, ???? ???? 
????? ???? ?? ??????? ?? ???? ??, ?? ??? ??-?? ???????? ?????? ????? ? 3 
 Decomposition reactions require energy either in the form of heat or light or electricity 
for breaking down the reactants. Write one equation each for decomposition reactions 
where energy is supplied in the form of heat, light and electricity.   
 
7. ???? ?????? ?? ??????? ???? ?? ??? ????? ???? ????  2 mL ??????? ???????????? ?? ????? 
???? ??? ? ?????? ?? ????? ??? ??? ???? ?? ????? ??? ??????? ??? ????? ????? ???? ?? ???? 
??? ????? ?? ????? ?? ?????? ???? ??? ????? ??? ?? ??????? ??? ? ????? ???? ??????? ?? 
?????? ??? ?? ??? ?? ?????? ?? ??? ????? ????? ? ??? ??? ???? ???? ??? ??? ?? ??? 
????? ?? ??????? ???, ??? ??? ??? ??????? ????? ???? ??? ????? ?  3 
???? 
 ??????? ??? ??????? ???? ???? ????? ?? ??? ?????? ??? ???? ???? ???? ??? ?? pH ??? 14 ?? ? 
?? ??? ??? ??????? ??? ???? ?????? ?? ??? ???????? ?????? ????? ? ???? ??? ???????? ?? 
???? ????? ? 
 2 mL of sodium hydroxide solution is added to a few pieces of granulated zinc metal 
taken in a test tube. When the contents are warmed, a gas evolves which is bubbled 
through a soap solution before testing. Write the equation of the chemical reaction 
involved and the test to detect the gas. Name the gas which will be evolved when the 
same metal reacts with dilute solution of a strong acid.  
OR 
 The pH of a salt used to make tasty and crispy pakoras is 14. Identify the salt and 
write a chemical equation for its formation. List its two uses.   
31/1 5 [P.T.O. 
8. (a) ????? ?? ??????? ?????? ????? ?? ?????? ???? ????? ?? ?  3 
 (b) ???? ???? ?????? ?????? ?? ??? ???? ???? ?????? ????? ????? ????? ?????? ??? ?? ?? 
?? ??????? ????? ?? ? ?? ?????? ?? ?????? ??? ??????? ?? ????? ????? ? 
 (a) Why are most carbon compounds poor conductors of electricity ? 
 (b) Write the name and structure of a saturated compound in which the carbon 
atoms are arranged in a ring. Give the number of single bonds present in this 
compound.  
 
9. ????????? ???????? ??????? ???? ????? ????????? ?? ??? ??? ????? ?? ?? ????? ????? ?  3 
 (a) ???? ???? (b) ????? ???? (c) ??????? 
 Name the hormones secreted by the following endocrine glands and specify one 
function of each : 
 (a) Thyroid (b) Pituitary (c) Pancreas    
 
10. ?????? ??? ???? ????? ??? ?? ??? ?? ???? ????? ? ?????? ??? ???? ???? ???? 
????? ??? ???? ???? ?????? ?? ?? ????? ???? ???? ?????? ?? ????????? ?? ???????? 
???? ?????? ??? ???? ?? ? ???? ??? ?? ????? ?? ??? ???? ????? ?  3 
 Write one main difference between asexual and sexual mode of reproduction. Which 
species is likely to have comparatively better chances of survival – the one reproducing 
asexually or the one reproducing sexually ? Give reason to justify your answer.   
 
11. ???? ?? ?????? ?? ???? ????? ? ?? “???? ????? ?? ?????? ?????????” ?? ?????? ????? 
???? ?? ?? ??? ?????? ?? ???? ?? ??? ?? ??? ?? ????? ??? ?????? ?? ??? ????? ????? ?  3 
???? 
 ???? ??? ?? ???? ?? ??? ?????? ?? ? ???? SI ???? ????? ? ????? ??? 40 cm ????? ???? ?? 
??? ?????? ?? ??? ?? ??? ????? ??? ??? –20 cm ????? ???? ?? ??? ?????? ?? ??? ?? ? ?? ?????? 
????? ?? ????? ???? ???? ????? ?