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TN 9th Tamil உள்ளத்தின் சீர் -விரிவானம் (துணைப்பாடம்) - தாய்மைக்கு வறட்சி இல்லை! Important Questions And Answers Study Material - QB365 Set A
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TN 9th Tamil உள்ளத்தின் சீர் -கவிதை பேழை (செய்யுள்) - மார்கழி பெருவிழா Important Questions And Answers Study Material - QB365 Set A
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TN 9th Tamil உயிருக்கு வேர்-இலக்கணம் - பகுபத உறுப்பிலக்கணம் Important Questions And Answers Study Material - QB365 Set A
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TN 9th Tamil அமுதென்று பேர் - இலக்கணம்-எழுத்து -அளபெடை Important Questions And Answers Study Material - QB365 Set A
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TN 9th Tamil அமுதென்று பேர்-துணைப்பாடம் - ஆறாம்திணை Important Questions And Answers Study Material - QB365 Set A
Published on: 30/07/2018
Some of the important questions are covered in this question paper from the Atomic Structure.
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Questions + Answers key
Take MCQ Science Test1.
Draw the structure of oxygen and sulphur atoms.
2.
What is isotone? Give an example.
3.
List the uses of isotopes?
4.
State the law of multiple proportions
5.
An atom has 11 protons, 11 electrons and 12 neutrons. What is the atomic number and the name of the element?
6.
The correct electronic configuration of potassium is
2,8,9
2,8,1
2,8,8,1
2,8,8,3
7.
The number of protons, neutrons and electrons present respectively in \(_{ 35 }^{ 80 }{ Br }\)
80, 80, 35
35, 55, 80
35, 35, 80
35, 45, 35
8.
The term nucleons refer to
Protons and electrons
only Neutrons
electrons and neutrons
Protons and neutrons
9.
Change in the number of neutrons in an atom changes it to
an ion
an isotope
an isobar
another element
10.
Among the following the odd pair is
8O18,9F19
18Ar40,7N14
14Si30, 15P31
24Cr54, 19K39
11.
The valency of Argon is ________
12.
The number of neutrons present in \(_{ 3 }^{ 7 }{ Li }\) is ------
13.
_________ isotope is used in the nuclear reactors.
14.
Total Number of electrons that can be accommodated in an orbit is given by_________.
15.
Calcium and Argon are examples of a pair of __________
16.
Arrange the following in the increasing order of atomic number
Calcium, Silicon, Boron, Magnesium, Oxygen, Helium, Neon, Sulphur, Fluorine and Sodium
17.
Ca2+ has completely filled outer shell. Justify your answer
18.
For an atom ‘X’, K, L and M shells are completely filled. How many electrons will be present in it?
19.
Compare the charge and mass of protons and electrons.
20.
Write the electronic configuration of K and Cl
21.
Name an element which has the same number of electrons in its first and second shell
1.
2.
Atoms of different elements with different atomic numbers and different mass numbers, but with the same number of neutrons are called isotones.
Example: Boron and Carbon have same number of neutrons.
3.
Uses of Radioactive isotopes:
1. Uranium 235 is used as fuel in nuclear reactor.
2. Cobalt 60 is used in the treatement of cancer.
3. Iodine 131 is used in the treatment of goitre.
4. C-14 is used in carbon dating.
4.
When two elements A and B combine together to form more than one compound, the masses of A which separately combines with the fixed mass of B are in simple ratio. This law was proposed by John Dalton.
5.
Atomic number = Number of protons = Number of electrons
Number of protons = Number of electrons = 11
∴ Atomic number = 11
Name of the element is Sodium.
6.
(c)
2,8,8,1
7.
(d)
35, 45, 35
8.
(d)
Protons and neutrons
9.
(b)
an isotope
10.
(d)
24Cr54, 19K39
11.
( )
zero
12.
( )
4
13.
( )
Uranium-235
14.
( )
2n2
15.
( )
isobars
16.
The elements in the increasing order of atomic no.
Helium, Boron, Oxygen, Neon, Sodium, Magnesium, Calcium, Silicon, Sulphur.
17.
Atomic number of calcium is 20. When it loses 2 electrons Ca2+ is formed.
\(Ca\quad -\quad 2e\quad \longrightarrow \quad C{ a }^{ +2 }\)
2,8,8,2 2,8,8
According to Bohr and Bury rule the outermost shell cannot have more than 8 electrons. So Ca2+ has completely filled outer shell.
18.
28 Electrons.
19.
| Particle | Mass | Charge |
| Proton | 1.672 x 10-24 g | 1.602 x 10-19 C |
| Electron | 9.108 x 10-28 g | -1.602 x 10-19 |
20.
| K | L | M | N | |
| Electronic configuration of K - | 2 | 8 | 8 | 1 |
| Electronic configuration of Cl - | 2 | 8 | 7 |
21.
Beryllium.
9th Standard Syllabus & Materials
9th Standard
TN 9th Tamil உள்ளத்தின் சீர் - திருக்குறள் Important Questions And Answers Study Material - QB365 Set A
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Tamilnadu Stateboard 9th Standard Subjects
Tamilnadu Stateboard Standards
