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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:

Class : Class 8
Yes it should be A .

Ans 2:

Class : Class 8
WWWWRRRROOOONNNNNNNNNNGGGGGGGGGGGGGGGGG

Ans 3:

Class : Class 5
And for this question must be A

Ans 4:

Class : Class 9
answer A

Ans 5:

Class : Class 9
The correct answer is AAAAAAA

Ans 6:

Class : Class 8
It has to be A.

Ans 7:

Class : Class 10
my apologies for the previous explanation answer is : C

Ans 8:

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:

Class : Class 9

Ans 10:

Class : Class 10
the answer is wrong.....it should be a

Ans 11:

Class : Class 10
thus answer is a

Ans 12:

Class : Class 8
it should be a

Ans 13:

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:

Class : Class 9
Yes the answer is A

Ans 15:

Class : Class 8
Answer is a

Ans 16:

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:

Class : Class 8
cation(Zn2 ) must be deposited to the cathode.

Ans 18:

Class : Class 8
answer is a

Ans 19:

Class : Class 8
the answer will be 'A'

Ans 20:

Class : Class 8
Yes it is A

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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:

Class : Class 3
B

Ans 2:

Class : Class 3

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Subject :NSO    Class : Class 7

Ans 1:

Class : Class 9
ans is c

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Subject :NSO    Class : Class 7

Ans 1:

Class : Class 9
Plug key is also a type of switch.

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Subject :NSO    Class : Class 5

Ans 1:

Class : Class 8
Yes, but in the given figure it is sedimentation

Ans 2:

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:

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:

Class : Class 5
Ya, filtration can also remove insoluble impurities but in this case sedimentation and decanation is more appropriate answer.

Ans 5:

Class : Class 8
c

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Subject :NSO    Class : Class 7

Ans 1:

Class : Class 9
every single sound has its own secondary waves, so the correct option must be option C.

Ans 2:

Class : Class 7
correct option is c

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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:

Class : Class 8

Ans 2:

Class : Class 5

Ans 3:

Class : Class 9

Ans 4:

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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Subject :NSO    Class : Class 8

Ans 1:

Class : Class 8
Why so? In both the cases soybean is present.

Ans 2:

Class : Class 9
Supposed to be only ABecause mustard is a non leguminous plantEven it can be rotated with soyabean

Ans 3:

Class : Class 8
Think in the way of leguminous crops

Ans 4:

Class : Class 8

Ans 5:

Class : Class 8
Both Wheat and Maize require rotation of crops.

Ans 6:

Class : Class 3
yeah right Triguna!!! in both cases soybean is present? why so?

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Subject :NSO    Class : Class 6

Ans 1:

Class : Class 7
They didn't give options

Ans 2:

Class : Class 7
Want option!

Ans 3:

Class : Class 8

Ans 4:

Class : Class 8
they didn't give the options to my computer

Ans 5:

Class : Class 6
They did not give options on my ipad .

Ans 6:

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:

Class : Class 6
They did not provide options on my laptop but option C is correct.

Ans 8:

Class : Class 6
they didnt give the options

Ans 9:

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:

Class : Class 6
They're not even giving me options

Ans 11:

Class : Class 6
No options

Ans 12:

Class : Class 6
they should be more careful

Ans 13:

Class : Class 7
I typed in c. What is this?

Ans 14:

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:

Class : Class 8
no options

Ans 16:

Class : Class 9
iT IS NOT LAPTOP'S MISTAKE IT IS THE WEBSITE'S MISTAKE ITSELF.

Ans 17:

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:

Class : Class 9
NO OPYIONS!

Ans 19:

Class : Class 8
they did not give options

Ans 20:

Class : Class 9
they didn't given on question page so all my friends and I missed that question

Ans 21:

Class : Class 6

Ans 22:

Class : Class 6
options are missing

Ans 23:

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:

Class : Class 9
my laptop din't provide the options

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Subject :NSO    Class : Class 4

Ans 1:

Class : Class 4

Ans 2:

Class : Class 4
c

Ans 3:

Class : Class 4
Correct answer is, C

Ans 4:

Class : Class 8
d

Ans 5:

Class : Class 6
correct ans is C

Ans 6:

Class : Class 4
Correct answer is C

Ans 7:

Class : Class 6
Correct answer is D.Because insectivores plants can photosynthesise.

Ans 8:

Class : Class 4
B,Care correct as they can not do photosynthesis , uses his leaves to catch food

Ans 9:

Class : Class 4
I think Dalso

Ans 10:

Class : Class 4
THE CORRECT ANSWER IS D BECAUSE THEY NEED TO OVERCOME DEFICIENCY OF NITROGEN

Ans 11:

Class : Class 5
D is correct

Ans 12:

Class : Class 4
c

Ans 13:

Class : Class 4
This is actually multiple Answer Q.It is silly!!!

Ans 14:

Class : Class 4

Ans 15:

Class : Class 2
the correct answer should be C

Ans 16:

Class : Class 4
B C D is the answers

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