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Garima Srivastava
Subject: Science
, asked on 9/2/18
What is static electricity
Answer
1
Fatima Nadeem
Subject: Science
, asked on 9/2/18
Plz answer question no. 7 ....with proper explaination
Answer
1
Ebin Joe
Subject: Science
, asked on 8/2/18
Please help me.
Answer
4
Parv
Subject: Science
, asked on 3/2/18
any atom achieves octet or duplet to become stable.....calcium's electronic configuration is 2,8,8,2...so it has 2 electrons in its valency shell....so it must achieve duplet and be stable but it needs to combine to form molecules to be stable.....why so??
Answer
3
Sanjay
Subject: Science
, asked on 2/2/18
Bohrs model work with an assumption elaborate the same
Answer
1
Manandeep Singh
Subject: Science
, asked on 2/2/18
the atomic number of magnesium is 12. what will be the atomic number of its ion and why
Answer
2
Prerit Rai
Subject: Science
, asked on 1/2/18
Explain s,p,d,f in chemistry.
Answer
5
Serena Singh
Subject: Science
, asked on 30/1/18
kindly answer Q37 with all the steps
The ratio of radii of hydrogen atom and its nucleus is 10
5
.Assuming the atom and the nucleus is spherical
(a)What will be the ratio of their sizes?.
(b) If an atom is represented by the planet earth 'Re=6.4 x 10
6
m ,estimate the size of the nucleus?.
Answer
4
Aryan Panda
Subject: Science
, asked on 28/1/18
Why do Argon, neon and helium do not react normally?
Answer
2
Renuka
Subject: Science
, asked on 27/1/18
Electronic configration of alumnium and draw its schematic diagram?
Answer
2
Suvam
Subject: Science
, asked on 26/1/18
Q. The number of electrons, protons and neutrons of elements are given below:
Element
A
B
C
D
E
Electrons
4
18
17
11
17
Protons
6
18
17
9
17
Neutrons
6
22
20
10
18
(a) Which of them is a cation?
(b) Which of them is an anion?
(c) Which is an atom of an Inert gas?
Q. An atom of an element has 7 electrons in its L shell.
(a) What is its atomic number?
(b) State its valency
(c) Identify the element.
Q. What Information do you get from the figure given below about the atomic number. mass number and valency of atom X?
Answer
1
Suvam
Subject: Science
, asked on 26/1/18
46. An element 'X' forms an oxide with formula
X
2
O
3
(a) State the valency of X,
(b) Write the formula of
(i) chloride X. (ii) sulphate of X
47. (a) Define the term mole.
(b) Calculate the no. of
(i) atoms
(ii) molecules in 124 grams of phosphorus.
P
4
(Given atomic mass of P = 31.0 u,
N
A
=
6
.
023
x
10
23
m
o
l
-
1
)
48 (a) What was Thomson's model of an atom?
(b) Write any two observations of Rutherford's model or atom.
49. . What were the conclusions of Rutherford's
α
-
particle scattering experiment.
Answer
1
Suvam
Subject: Science
, asked on 26/1/18
46. An element 'X' forms an oxide with formula
X
2
O
3
(a) State the valency of X,
(b) Write the formula of
(i) chloride X. (ii) sulphate of X
47. (a) Define the term mole.
(b) Calculate the no. of
(i) atoms
(ii) molecules in 124 grams of phosphorus.
P
4
(Given atomic mass of P = 31.0 u,
N
A
=
6
.
023
x
10
23
m
o
l
-
1
)
48 (a) What was Thomson's model of an atom?
(b) Write any two observations of Rutherford's model or atom.
49. . What were the conclusions of Rutherford's
α
-
particle scattering experiment.
50. The number of electrons, protons and neutrons of elements are given below:
Element
A
B
C
D
E
Electrons
4
18
17
11
17
Protons
6
18
17
9
17
Neutrons
6
22
20
10
18
(a) Which of them is a cation?
(b) Which of them is an anion?
(c) Which is an atom of an Inert gas?
51. An atom of an element has 7 electrons in its L shell.
(a) What is its atomic number?
(b) State its valency
(c) Identify the element.
Answer
1
Suvam
Subject: Science
, asked on 26/1/18
Question number 38, 39, 40, 41, 42, 43, 44,
Answer
1
Suvam
Subject: Science
, asked on 26/1/18
Question number 21
21.
In the notation of Nitrogen
N
7
14
,
what do the atom gains three electrons ?
Answer
2
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What are you looking for?
The ratio of radii of hydrogen atom and its nucleus is 105.Assuming the atom and the nucleus is spherical
(a)What will be the ratio of their sizes?.
(b) If an atom is represented by the planet earth 'Re=6.4 x 106m ,estimate the size of the nucleus?.
(a) Which of them is a cation?
(b) Which of them is an anion?
(c) Which is an atom of an Inert gas?
Q. An atom of an element has 7 electrons in its L shell.
(a) What is its atomic number?
(b) State its valency
(c) Identify the element.
Q. What Information do you get from the figure given below about the atomic number. mass number and valency of atom X?
(a) State the valency of X,
(b) Write the formula of
(i) chloride X. (ii) sulphate of X
47. (a) Define the term mole.
(b) Calculate the no. of
(i) atoms
(ii) molecules in 124 grams of phosphorus.
(Given atomic mass of P = 31.0 u, )
48 (a) What was Thomson's model of an atom?
(b) Write any two observations of Rutherford's model or atom.
49. . What were the conclusions of Rutherford's particle scattering experiment.
(a) State the valency of X,
(b) Write the formula of
(i) chloride X. (ii) sulphate of X
47. (a) Define the term mole.
(b) Calculate the no. of
(i) atoms
(ii) molecules in 124 grams of phosphorus.
(Given atomic mass of P = 31.0 u, )
48 (a) What was Thomson's model of an atom?
(b) Write any two observations of Rutherford's model or atom.
49. . What were the conclusions of Rutherford's particle scattering experiment.
50. The number of electrons, protons and neutrons of elements are given below:
(a) Which of them is a cation?
(b) Which of them is an anion?
(c) Which is an atom of an Inert gas?
51. An atom of an element has 7 electrons in its L shell.
(a) What is its atomic number?
(b) State its valency
(c) Identify the element.
21. In the notation of Nitrogen what do the atom gains three electrons ?