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aditya apurva from DAV public School, Duttnagar
Subject :NSO    Class : Class 9

Ans 1:

ADITYA KISHOR from dps, gaya
Class : Class 9

Ans 2:

Aarju Pal from Arambagh Vivekananda Academy, Arambagh
Class : Class 9
yes, (a) is the right answer as due to accelaration by gravity, velocity of any freely falling object will increase continuously. So, (b) is wrong as h1, h2 and h3 are given equal, (c)is wrong too as it is given that covered distance decreases after every 5 seconds, and (d) is also wrong for the same reason.

Ans 3:

Ankur Kumar from Delhi Public School, Ranchi
Class : Class 9
Option D is the correct answer as the ratio between H1 H2 and H3 is 1: 3 : 5.

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from , Nanded
Subject :NSO    Class : Class 9

Few statements regarding the distribution of electrons in the energy shells are given. Which of the following statements is not correct?

A For fourth energy shell (N), the maximum number of electrons is 32 according to 2n2 rule.
B When N is the outermost shell of an atom, it can accommodate a maximum of 8 electrons only.
C The filling of the fourth shell begins even before the third shell is completely filled.
D Fifth shell can accommodate 50 electrons according to 2n2 rule.


Ans 1:

RUDRANSH from Little Angels High School, Gwalior
Class : Class 8

Ans 2:

Ankur Kumar from Delhi Public School, Ranchi
Class : Class 9
Option B is wrong . As it is talking of the energy shell. OR might be the question is incorrect as the all the options are correct as per my information.

Ans 3:

Sreyashi Ganguli from Bishop Cotton Girls School, Bengaluru
Class : Class 9
ans should no doubt be c because of the Hund 's rule and also fifth shell does accommodate 50 electrons according to 2n^2 :2*5^2=2*25=50.

Ans 4:

from d.g.v. sr. sec. school, rohtak
Class : Class 9
(D) is correct

Ans 5:

Sunita Kundu from Scholars rosary senior secondary school , Rohtak
Class : Class 10
Answer should be either B or c because both of them are incorrect

Ans 6:

smriti khuntia from apeejay school,nerul, navi mumbai
Class : Class 9
C should be the answer! a- 2*4^2=32. b-the outermost shell always has 8 to gain perfect stability or become a noble gas. c-wrong, filling always starts from the first, second, third, THEN fourth. d-2*5^2=50

Ans 7:

Aarju Pal from Arambagh Vivekananda Academy, Arambagh
Class : Class 9
(a) is no doubt right, (b) may be wrong, (c) is right and (d) is also right.

Ans 8:

Sunita Kundu from Scholars rosary senior secondary school , Rohtak
Class : Class 10

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Chaitanya Gawade from JPS, Pune
Subject :NSO    Class : Class 9

Ans 1:

Ankur Kumar from Delhi Public School, Ranchi
Class : Class 9
Volume of the solid cube =(25*25*25)/1000000 cubic metre. Mass of the solid cube = the mass of the body which can be placed on it to completely submerge it Density = 0.1kg/ 125*(10)^6=800kg/m^3

Ans 2:

Ankur Kumar from Delhi Public School, Ranchi
Class : Class 9
Volume of the solid cube =(25*25*25)/1000000 cubic metre. Mass of the solid cube = the mass of the body which can be placed on it to completely submerge it Density = 0.1kg/ 125*(10)^6=800kg/m^3

Ans 3:

Arnav Bhatnagar from RFS, Navi Mumbai
Class : Class 8

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Chaitanya Gawade from JPS, Pune
Subject :NSO    Class : Class 9

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Chaitanya Gawade from JPS, Pune
Subject :NSO    Class : Class 9

Study the given figure carefully and select the incorrect statement(s).

I. A white ring is formed which is closer to the hydrochloric acid end of the tube because hydrogen chloride fumes diffuse faster than ammonia.
II. Ratio of number of atoms of ammonia to that of hydrogen chloride which combine to form 3.6138 × 1024 atoms of ammonium chloride is 1 : 3.
III. 3.4 g of ammonia combines with 7.3 g of hydrogen chloride to form 10.7 g of ammonium chloride.
IV. If temperature is increased, white ring will be formed exactly in the middle of the tube.
(Given : Atomic mass of H = 1 u, N = 14 u, Cl = 35.5 u)

A II and IV only
B II and III only
C I, II and IV only
D I only


How to solve this

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Chaitanya Gawade from JPS, Pune
Subject :NSO    Class : Class 9

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Ajoy Bhuyan from DELHI PUBLIC SCHOOL, Bongaigaon
Subject :NSO    Class : Class 4

Ans 1:

Ajoy Bhuyan from DELHI PUBLIC SCHOOL, Bongaigaon
Class : Class 4
b ans

Ans 2:

kushagra chaturvedi from Podar Internation School Chinchwad, Pune
Class : Class 5
Thus ans is c not BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB

Ans 3:

kushagra chaturvedi from Podar Internation School Chinchwad, Pune
Class : Class 5
THIS IS NOT POSSIBLE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!Because you can GOOGLE IT.......................................... MY OPINION- Kushagra Chaturvedi

Ans 4:

kushagra chaturvedi from Podar Internation School Chinchwad, Pune
Class : Class 5

Ans 5:

Ajoy Bhuyan from DELHI PUBLIC SCHOOL, Bongaigaon
Class : Class 4

Ans 6:

kushagra chaturvedi from Podar Internation School Chinchwad, Pune
Class : Class 5
Thus ans is c not BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB

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Chaitanya Gawade from JPS, Pune
Subject :NSO    Class : Class 9

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Chaitanya Gawade from JPS, Pune
Subject :NSO    Class : Class 9

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Chaitanya Gawade from JPS, Pune
Subject :NSO    Class : Class 9

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