Term -2 Class:8 Science 4. Atomic Structure - Choose - clickhere

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Term -2 Class:8 Science 4. Atomic Structure

வினாக்களை படித்து , புரிந்துகொண்டு விடைகளை தேர்ந்தெடுக்கவும்:
Understand the Question and choose the Correct answers:
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5 நிமிடத்திற்குள் கவனமாகவும் , விரைவாகவும் விளையாட்டை முடிக்க.
விளையாடி முடித்தபின் , அனைத்தையும் எழுதிப்பார்க்கவும். நன்றி.
உங்கள் முயற்சிக்கு வாழ்த்துகள்.

 

1. Crookes’ rays are otherwise called __________
   1.   Cathode rays
   2.   Anode rays
   3.   X-rays
   4.   Gamma rays
2. Cathode rays are nothing but_________
   1.   Electrons
   2.   Neutrons
   3.   Protons
   4.   Positrons
3. The presence of positively charged particles in the atom has been first predicted by ________
   1.   Goldstein
   2.   John Dalton
   3.   Neil Bohr
   4.   J.J. Thomson
4. Neutrons were discovered by _____________
   1.   James Chadwick
   2.   Goldstein
   3.   Faraday
   4.   Dalton
5. ___________atom model was called plum pudding model
   1.   Thomson's
   2.   Ruth erford's
   3.   Bohr's
   4.   Dalton's
6. The electrons revolving in the outer most orbit are called
   1.   Valence Electrons
   2.   Outer electrons
   3.   Inner electrons
   4.   Non of the above
7. Which among the following are said to be chemically inert?
   1.   Helium and Neon
   2.   Hydrogen atom and helium
   3.   Hydrogen and Neon
   4.   Neon and Iron
8. The purpose of an atom to possess valency is
   1.   All the above
   2.   To attain the chemical inertness
   3.   To attain stable electronic configuration
   4.   To form a new stable molecule or species
9. Sodium (atomic number = 11) and chlorine (atomic number = 17) always form ______ and ______ valencies respectively.
   1.   Positive and negative
   2.   Negative and positive
   3.   Negative and negative
   4.   Positive and positive
10. When an atom loses one or more electrons, it forms ______ charge and ______valency respectively
    1.   Positive charge and positive valency
    2.   Positive charge and negative valency
    3.   Negative charge and negative valency
    4.   Negative charge and positive valency