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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

Ans 2:

Class : Class 3
And for this question must be A

Ans 3:

Class : Class 8
the answer will be 'A'

Ans 4:

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

Ans 5:

Class : Class 9
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 6:

Class : Class 9
thus answer is a

Ans 7:

Class : Class 8
WWWWRRRROOOONNNNNNNNNNGGGGGGGGGGGGGGGGG

Ans 8:

Class : Class 8
answer A

Ans 9:

Class : Class 9
the answer is wrong.....it should be a

Ans 10:

Class : Class 9
my apologies for the previous explanation answer is : C

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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 7
ans is c

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Subject :NSO    Class : Class 7

Ans 1:

Class : Class 8
Plug key is also a type of switch.

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Subject :NSO    Class : Class 5

Ans 1:

Class : Class 5
Yes, but in the given figure it is sedimentation

Ans 2:

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 3:

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

Ans 4:

Class : Class 7
c

Ans 5:

Class : Class 7
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.

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Subject :NSO    Class : Class 7

Ans 1:

Class : Class 7
correct option is c

Ans 2:

Class : Class 7
every single sound has its own secondary waves, so the correct option must be option 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 9

Ans 3:

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
Think in the way of leguminous crops

Ans 2:

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

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Subject :NSO    Class : Class 6

Ans 1:

Class : Class 6
Want option!

Ans 2:

Class : Class 6

Ans 3:

Class : Class 7
my laptop din't provide the options

Ans 4:

Class : Class 7
they didn't given on question page so all my friends and I missed that question

Ans 5:

Class : Class 6
NO OPYIONS!

Ans 6:

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 7:

Class : Class 6
they should be more careful

Ans 8:

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

Ans 9:

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

Ans 10:

Class : Class 7
They didn't give options

Ans 11:

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

Ans 12:

Class : Class 7
they didn't give the options to my computer

Ans 13:

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:

Class : Class 6
iT IS NOT LAPTOP'S MISTAKE IT IS THE WEBSITE'S MISTAKE ITSELF.

Ans 15:

Class : Class 7

Ans 16:

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 17:

Class : Class 6
No options

Ans 18:

Class : Class 8
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 19:

Class : Class 7
no options

Ans 20:

Class : Class 6
they did not give options

Ans 21:

Class : Class 6
they didnt give the options

Ans 22:

Class : Class 6
options are missing

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Subject :NSO    Class : Class 4

Ans 1:

Class : Class 4
Correct answer is C

Ans 2:

Class : Class 4
Correct answer is, C

Ans 3:

Class : Class 6
d

Ans 4:

Class : Class 2
the correct answer should be C

Ans 5:

Class : Class 5
correct ans is C

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