मराठी
सी.आई.एस.सी.ई.आयसीएसई ICSE Class 8

Dalton said that ______ could not be divided.

Advertisements
Advertisements

प्रश्न

Dalton said that ______ could not be divided.

रिकाम्या जागा भरा
Advertisements

उत्तर

Dalton said that atoms could not be divided.

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 4: Atomic Structure - Exercise [पृष्ठ ५१]

APPEARS IN

एस.पी. सिंह Concise Chemistry [English] Class 8 ICSE
पाठ 4 Atomic Structure
Exercise | Q 1.1 | पृष्ठ ५१

संबंधित प्रश्‍न

With the help of given Table, find out the mass number of oxygen.

Composition of Atoms of the First Eighteen Elements with Electron Distribution in Various Shells
Name of Element Symbol Atomic Number Number of protons Number of Neutrons Number of Electrons Distribution of Electrons Valency
K L M N
Hydrogen H 1 1 - 1 1 - - - 1
Helium He 2 2 2 2 2 - - - 0
Lithium Li 3 3 4 3 2 1 - - 1
Beryllium Be 4 4 5 4 2 2 - - 2
Boron B 5 5 6 5 2 3 - - 3
Carbon C 6 6 6 6 2 4 - - 4
Nitrogen N 7 7 7 7 2 5 - - 3
Oxygen O 8 8 8 8 2 6 - - 2
Fluorine F 9 9 10 9 2 7 - - 1
Neon Ne 10 10 10 10 2 8 - - 0
Sodium Na 11 11 12 11 2 8 1 - 1
Magnesium Mg 12 12 12 12 2 8 2 - 2
Aluminium Al 13 13 14 13 2 8 3 - 3
Silicon Si 14 14 14 14 2 8 4 - 4
Phosphorus P 15 15 16 15 2 8 5 - 3.5
Sulphur S 16 16 16 16 2 8 6 - 2
Chlorine Cl 17 17 18 17 2 8 7 - 1
Argon Ar 18 18 22 18 2 8 8   0

 Fill in the blank

An ion which has a positive charge is called a ..................


What is variable valency? Name two elements having variable valency and state their valencies.


Draw the orbital diagram of `""_20^40"Ca"^(2+)` ion and state the number of three fundamental particles present in it.


Elements X, Y and Z have atomic numbers 6, 9 and 12 respectively. Which one:

  1. Forms an anion
  2. Forms a cation
  3. Has four electrons in its valence shell?

From the symbol `""_2^4"He"`  for the element helium, write down the mass number and the atomic number of the element.


The diagram represents an isotope of hydrogen [H]. Answer the following:


Atomic no. = 1
Mass no. = 1

Do isotopes have the same atomic number or the same mass number?


Draw the structure of the following atoms showing the nucleus containing – protons, neutrons and the orbits with the respective electron:

Carbon [At. no. = 6, Mass no. = 12]


Explain the following terms.

  1. Proton
  2. Electron
  3. Neutron.

The elementary particles such as protons and neutrons are collectively called ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×