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Kshitij Gupta from St Kabir din, Ahmedabad
Subject :NSO    Class : Class 8

The diagram shows a beaker containing a solution of zinc sulphate and two carbon electrodes. A battery is placed next to it. In order that the electrode P be plated with zinc,


A P must be connected to S and Q to R
B P must be connected to Q and S to R
C P must be connected to R and Q to S
D P and Q must be connected to R.


The answer would be a as znso4 wold breakdown into zn 2and so42-ions .the zn 2 would be attracted towards cathode(negative terminal) so p would be attached to negative terminal and therefore the answer is a.

Ans 1:

Akshara from NPS, Bengaluru
Class : Class 8
Yes it should be A .

Ans 2:

Riya Singhani from BVB vidhyashram, jaipur
Class : Class 8
WWWWRRRROOOONNNNNNNNNNGGGGGGGGGGGGGGGGG

Ans 3:

Tanush from presidency east, Bangalore
Class : Class 5
And for this question must be A

Ans 4:

Abhay Agarwal from St Francis School, Ghaziabad
Class : Class 9
answer A

Ans 5:

from Bhandari Public School, KHANDWA
Class : Class 9
The correct answer is AAAAAAA

Ans 6:

bipasana from KV IIT Kanpur, Kanpur
Class : Class 8
It has to be A.

Ans 7:

Raghav Tyagi from birla vidya niketan, new delhi
Class : Class 10
my apologies for the previous explanation answer is : C

Ans 8:

Nishtha Neelabh from Lok Puram Public School, Thane West
Class : Class 6
answer should be A, as hydrogen is not released at cathode if the other cation is Zinc or below in the electrochemical series

Ans 9:

Abhay Agarwal from St Francis School, Ghaziabad
Class : Class 9

Ans 10:

Dhars from DPS EAST Bangalore , Bengaluru
Class : Class 10
the answer is wrong.....it should be a

Ans 11:

Raghav Tyagi from birla vidya niketan, new delhi
Class : Class 10
thus answer is a

Ans 12:

aditya arora from Heritage Experiential Learning School, gurugram
Class : Class 8
it should be a

Ans 13:

Raghav Tyagi from birla vidya niketan, new delhi
Class : Class 10
In reactivity series hydrogen is below zinc and is less reactive than zinc. As hydrogen below zinc therefore will reduce more and earlier than zinc , hence will go to cathode and zinc will reduced or deposit at anode. therefore P will be connected to R and Q to S.hence ans is :C

Ans 14:

Anshuman D from MVM, Hyderabad
Class : Class 9
Yes the answer is A

Ans 15:

Chatresh ramasai gudi from Bgsnps , Bangalore
Class : Class 8
Answer is a

Ans 16:

Amol Athawale from WoodRidge High, aurangabad
Class : Class 8
i do feel that correct answer is A.as P has to be electroplated ,it must be on cathode(-ve).so,correct is =A

Ans 17:

tamojit das from techno India Group Public School , Chinsura
Class : Class 8
cation(Zn2 ) must be deposited to the cathode.

Ans 18:

Bhagyesh Kamal from DPS, Mumbai
Class : Class 8
answer is a

Ans 19:

Sounak halder from Kendriya Vidyalaya Cossipore, kolkata
Class : Class 8
the answer will be 'A'

Ans 20:

Chaitanya L K from SKCHEC, bangalore
Class : Class 8
Yes it is A

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H KRITHIK from kendriya vidyalaya, chennai
Subject :NSO    Class : Class 3

A note is shown here which Ravi has made about different types of house. Unfortunately when he had finished writing, some ink spilt over the page and covered some of the key words.
A wooden house made on a boat is called . It is common in Kashmir and . In areas with heavy rainfall houses are common. are built of snow and are found in very cold countries.
Select the correct sequence of hidden words to complete the note.

A Caravan, Rajasthan, Tent, Igloos
B Houseboat, Kerala, Stilt, Igloos
C Houseboat, Delhi, Kutcha, Igloos
D Tent, Karnataka, Caravan, Igloos

Ans 1:

Varsha from Nps banashankari Bangalore, Bangalore
Class : Class 3
B

Ans 2:

Dishen dharmenra patel from Anand niketan to the satellite , Ahmedabad
Class : Class 3

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from , Kolkata
Subject :NSO    Class : Class 7

Ans 1:

Medha Bhutani from Christ Academy, Bengaluru
Class : Class 9
ans is c

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from , Kolkata
Subject :NSO    Class : Class 7

Ans 1:

Sriyansh from Surabhi , Hosapete
Class : Class 9
Plug key is also a type of switch.

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Raghav Mittal from DAV Public School, ludhiana
Subject :NSO    Class : Class 5

Ans 1:

Gauri Singh from St. John's School, Marhauli, Varanasi
Class : Class 8
Yes, but in the given figure it is sedimentation

Ans 2:

A Andriya from Lalaji Memorial Omega International School, Chennai
Class : Class 8
sedimentation and decantation is the answer . but filtration can not come because we can see in the picture itself that the particles are big ,that's why sedimentation and decantation . if the particles are small but yet insoluble , then only it is filtration . I hope that you understood.

Ans 3:

Mallika Gupta from NPS indiranagar, Bangalore
Class : Class 9
it needs to be sedimentation and decantation because the insoluble material present in the liquid is quite heavy you only perform filtration when the particles float over the surface of the water

Ans 4:

Shivangi from St. Michael's High School, Patna
Class : Class 5
Ya, filtration can also remove insoluble impurities but in this case sedimentation and decanation is more appropriate answer.

Ans 5:

ARNAV GARG from PRUDENCE SCHOOL, New Delhi
Class : Class 8
c

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from , Kolkata
Subject :NSO    Class : Class 7

Ans 1:

Medha Bhutani from Christ Academy, Bengaluru
Class : Class 9
every single sound has its own secondary waves, so the correct option must be option C.

Ans 2:

RAHUL S ROY from ST.XAVIERS HIGH SCHOOL,VAPI, VAPI,GUJARAT
Class : Class 7
correct option is c

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Ethel shiju from National Public School Indiranagar, Bangalore
Subject :NSO    Class : Class 8

Read the given statements and select the correct option.
Statement 1 : Phosphorus burns in air at room temperature.
Statement 2 : It is an example of spontaneous combustion.

A Both statements 1 and 2 are true and statement 2 is the correct explanation of statement 1.
B Both statements 1 and 2 are true but statement 2 is not the correct explanation of statement 1.
C Statement 1 is true and statement 2 is false.
D Both statements 1 and 2 are false.


I say it is option a but they say it is b....But isn’t this definitely due to spontaneous combustion?

Ans 1:

Student from School, City
Class : Class 8

Ans 2:

arnav from the gurukul, Panchkula
Class : Class 5

Ans 3:

Yash Bindal from Global Indian International School, Singapore
Class : Class 9

Ans 4:

Bhuvanesh Singla from SCTS, Bengaluru
Class : Class 8
Hi, the statement 2 is true but just tells about the type type combustion to which the reaction given in statement belong. it does not tell about actual cause of burning of phosphorus in air at room temperature. the reason for statement 1 is that phosphorus is a highly reactive element that's why burns in air at room temperature.

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Ethel shiju from National Public School Indiranagar, Bangalore
Subject :NSO    Class : Class 8

Ans 1:

Triguna from Kendriya Vidyalaya No.1 Salt Lake, Kolkata
Class : Class 8
Why so? In both the cases soybean is present.

Ans 2:

Anshuman D from MVM, Hyderabad
Class : Class 9
Supposed to be only ABecause mustard is a non leguminous plantEven it can be rotated with soyabean

Ans 3:

S V Harini from Vailankanni public school , Krishnagiri
Class : Class 8
Think in the way of leguminous crops

Ans 4:

Aadavamoorthy from GIIS, Bangalore
Class : Class 8

Ans 5:

Aadavamoorthy from GIIS, Bangalore
Class : Class 8
Both Wheat and Maize require rotation of crops.

Ans 6:

Pradanya from KV IIT, Chennai
Class : Class 3
yeah right Triguna!!! in both cases soybean is present? why so?

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Anurag Basistha from Prudence School Dwarka 16 B, Delhi
Subject :NSO    Class : Class 6

Ans 1:

Sharmi Chowdhury from G.D Birla Centre For Education , Kolkata
Class : Class 7
They didn't give options

Ans 2:

Ritika Bakshi from Techno India Group public School Hooghly, Chinsurah
Class : Class 7
Want option!

Ans 3:

Aniket Ghosh from DAV Public School Haldia, Haldia
Class : Class 8

Ans 4:

Ahaan Pathak from Treamis World School, Bangalore
Class : Class 8
they didn't give the options to my computer

Ans 5:

Bhabani Prasad from Narayan School, Kolkata
Class : Class 6
They did not give options on my ipad .

Ans 6:

Sudarshana Bhattacharya from Maharishi vidya mandir, Hyderabad
Class : Class 7
I got the question with the options in my laptop. For those who did not get the options : it is the website's fault

Ans 7:

Aarush Laddha from NCFE, bengaluru
Class : Class 6
They did not provide options on my laptop but option C is correct.

Ans 8:

Shourya Ganesh from The Green Acres Academy, Mumbai
Class : Class 6
they didnt give the options

Ans 9:

Kshitij from Sams, Bangalore
Class : Class 6
they MUST and SHOULD be more CAREFUL. No options??? Then, how should we answer their question??? they take no actions! look:-a person has commented a year ago but?NO RESPONSE

Ans 10:

Raghav from Shalom Hills International school, Gurgaon
Class : Class 6
They're not even giving me options

Ans 11:

Riddhi from St Ursula high school, PIMPRI CHINCHWAD
Class : Class 6
No options

Ans 12:

BHAVYA JHA from GLOBAL CITY INTERNATIONAL SCHOOL, BANGALORE
Class : Class 6
they should be more careful

Ans 13:

Ishaan Mishra from Sai International School, Bhubaneswar
Class : Class 7
I typed in c. What is this?

Ans 14:

khushi Joshi from Svkm , Mumbai
Class : Class 9
They did not give the options on my iPad so I couldn't see which was the correct ans. something needs to be done about this problem.

Ans 15:

Ankush Ghosh from DPS, Doha
Class : Class 8
no options

Ans 16:

Hamsavarshini Swaminathan from St Anns Senior Secondary School, Roorkee
Class : Class 9
iT IS NOT LAPTOP'S MISTAKE IT IS THE WEBSITE'S MISTAKE ITSELF.

Ans 17:

Pulkit Krishna from St. Paul's High School, Hajipur
Class : Class 6
The shadow will be whole black as the book is an opaque object and will not allow any light to pass through it so on the screen it will form a shadow. And the rest that is the ring, no light will reach it thus how can its shadow be formed?

Ans 18:

Hamsavarshini Swaminathan from St Anns Senior Secondary School, Roorkee
Class : Class 9
NO OPYIONS!

Ans 19:

Bharat from Geetanjali Olympiad school, Bangalore
Class : Class 8
they did not give options

Ans 20:

Anmol kathar from deogiri global academy, aurangabad
Class : Class 9
they didn't given on question page so all my friends and I missed that question

Ans 21:

Shourya Ganesh from The Green Acres Academy, Mumbai
Class : Class 6

Ans 22:

Naman from Svm, Nalasopara
Class : Class 6
options are missing

Ans 23:

Hamsavarshini Swaminathan from St Anns Senior Secondary School, Roorkee
Class : Class 9
They did not give options so that is why it went wrong. these kind of incidents happen very frequently in SOF

Ans 24:

Ayush Anand Sharma from GEMS international school , Gurgaon
Class : Class 9
my laptop din't provide the options

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Anshu Manglik from Delhi Public School, Gurgaon
Subject :NSO    Class : Class 4

Ans 1:

arsh from nps, bangalore
Class : Class 4

Ans 2:

Daksh Chanani from Sri Sri academy, Kolkata, HOWRAH
Class : Class 4
c

Ans 3:

Suniti Kumar Ghosh from Saraswati Devi Public School , Salar
Class : Class 4
Correct answer is, C

Ans 4:

DHEER PANDEY from Sentia School, Hyderabad
Class : Class 8
d

Ans 5:

Sankeerth Sunil from Shishya BELM public School, Bangalore
Class : Class 6
correct ans is C

Ans 6:

Saiesh from Sindhi high school, Bangalore
Class : Class 4
Correct answer is C

Ans 7:

Agriye Kamboj from ST.XAVIER SEC SE CO ed Bhopal, BHOPAL
Class : Class 6
Correct answer is D.Because insectivores plants can photosynthesise.

Ans 8:

RAYANSH MISHRA from VIBGYOR HIGH, Pune
Class : Class 4
B,Care correct as they can not do photosynthesis , uses his leaves to catch food

Ans 9:

RAYANSH MISHRA from VIBGYOR HIGH, Pune
Class : Class 4
I think Dalso

Ans 10:

Vibha from Birla Public School, Doha
Class : Class 4
THE CORRECT ANSWER IS D BECAUSE THEY NEED TO OVERCOME DEFICIENCY OF NITROGEN

Ans 11:

Kriti Bhonsale from Delhi Public School, Bengaluru
Class : Class 5
D is correct

Ans 12:

Pankaj Rajput from RBK GLOBAL SCHOOL, THANE
Class : Class 4
c

Ans 13:

Madhura Mageshwaran from zurich school, zurich
Class : Class 4
This is actually multiple Answer Q.It is silly!!!

Ans 14:

Arnesh from DPS Mathura Road , New Delhi
Class : Class 4

Ans 15:

Vrishank Sai Anand from GEMS Modern Academy, Dubai
Class : Class 2
the correct answer should be C

Ans 16:

Rishi from Deens Academy, BENGALURU
Class : Class 4
B C D is the answers

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