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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:

Raghav Tyagi from birla vidya niketan, new delhi
Class : Class 8
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 2:

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

Ans 3:

Abhay Agarwal from St Francis School, Ghaziabad
Class : Class 8

Ans 4:

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

Ans 5:

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

Ans 6:

Raghav Tyagi from birla vidya niketan, new delhi
Class : Class 8
my apologies for the previous explanation answer is : C

Ans 7:

Abhay Agarwal from St Francis School, Ghaziabad
Class : Class 8
answer A

Ans 8:

Raghav Tyagi from birla vidya niketan, new delhi
Class : Class 8
thus answer is a

Ans 9:

Dhars from DPS EAST Bangalore , Bengaluru
Class : Class 8
the answer is wrong.....it should be a

Ans 10:

Tanush from Presidency, Bangalore
Class : Class 3
And for this question must be 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:

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

Ans 2:

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

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Sarthak Pattnaik from Salt Lake School, Kolkata
Subject :NSO    Class : Class 7

Ans 1:

Medha Bhutani from Christ Academy, Bengaluru
Class : Class 7
ans is c

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Sarthak Pattnaik from Salt Lake School, Kolkata
Subject :NSO    Class : Class 7

Ans 1:

Sriyansh from Surabhi , Hosapete
Class : Class 8
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:

Andriya Arockia Ranjan from Lalaji Memorial Omega International School Kolapakkam Chennai, Chennai
Class : Class 6
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 2:

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 3:

Gauri Singh from St. John's School, Marhauli, Varanasi
Class : Class 5
Yes, but in the given figure it is sedimentation

Ans 4:

Mallika Gupta from NPS Koramangala, Bangalore
Class : Class 7
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 5:

ARNAV GARG from PRESIDIUM SCHOOL, New Delhi
Class : Class 6
c

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Sarthak Pattnaik from Salt Lake School, Kolkata
Subject :NSO    Class : Class 7

Ans 1:

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

Ans 2:

Medha Bhutani from Christ Academy, Bengaluru
Class : Class 7
every single sound has its own secondary waves, so the correct option must be option 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:

arnav from the gurukul, Panchkula
Class : Class 8

Ans 2:

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.

Ans 3:

Yash Bindal from Global Indian International, Singapore
Class : Class 8

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

Ans 1:

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

Ans 2:

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

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Ashoke Basistha from presidium dwarka 16 B, delhi
Subject :NSO    Class : Class 6

Ans 1:

Ritika Bakshi from Techno India Group public School Hooghly, Chinsurah
Class : Class 6
Want option!

Ans 2:

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

Ans 3:

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 4:

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

Ans 5:

Ahaan Pathak from Treamis World School, Bangalore
Class : Class 7
they didn't give the options to my computer

Ans 6:

Anmol kathar from deogiri global academy, aurangabad
Class : Class 7
they didn't given on question page so all my friends and I missed that question

Ans 7:

khushi Joshi from Svkm , Mumbai
Class : Class 7
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 8:

Hamsavarshini Swaminathan from St Anns Senior Secondary School, Roorkee
Class : Class 6
They did not give options so that is why it went wrong. these kind of incidents happen very frequently in SOF

Ans 9:

Ankush Ghosh from DPS, Doha
Class : Class 6
no options

Ans 10:

Ayush sharma from GEMS international school , Gurgaon
Class : Class 6
my laptop din't provide the options

Ans 11:

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

Ans 12:

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

Ans 13:

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 14:

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

Ans 15:

Hamsavarshini Swaminathan from St Anns Senior Secondary School, Roorkee
Class : Class 6
NO OPYIONS!

Ans 16:

Aniket Ghosh from DAV Public School Haldia, Haldia
Class : Class 6

Ans 17:

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

Ans 18:

Hamsavarshini Swaminathan from St Anns Senior Secondary School, Roorkee
Class : Class 6
iT IS NOT LAPTOP'S MISTAKE IT IS THE WEBSITE'S MISTAKE ITSELF.

Ans 19:

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

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

Ans 1:

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

Ans 2:

Sankeerth S from shishy BEML public school, Bangalore
Class : Class 4
correct ans is C

Ans 3:

DHEER PANDEY from CORNERSTONE SCHOOL, Hyderabad
Class : Class 5
d

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