Class 9 Science Chapter 4 Structure Of The Atom Quiz 9 (25 MCQs)

Quiz Instructions

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1. Which experiment led to the discovery of protons?
2. A patient is diagnosed of having cancer. Which isotope is used to treat the patient?
3. Which of the following correctly represent the electronic distribution in the Mg atom?
4. One of the first ideas about the makeup of matter was .....
5. Which of the following elements contains the greatest amount of protons?
6. Protons are present in
7. Do electrons contribute to the mass of an atom?
8. Bohr discovered that electrons are located in
9. $Ag_{47}^{108}$
10. What is the number of electrons in the valence shell of boron (B)?
11. An atom of chlorine-37 has 17 electrons. How many neutrons does an atom of chlorine-37 contain?
12. Which of the following is the best evidence that the particles that make up a cathode ray had a negative charge?
13. A pure sample of ammonia contains 14 g of nitrogen and 3 grams of hydrogen. A second sample of pure ammonia contains 28 g nitrogen and 6 g of hydrogen. This is an example of the
14. . Subatomic particles that are neutral in charge
15. In the Bohr model of the atom, electrons are said to move in specific paths around the nucleus. What are these paths called?
16. Value representing the number of protons in an element
17. What is the default charge of an element on the periodic table?
18. Why was the Thomson's Model of an atom failed?i. It could not explain the screening of negative charges from that of positiveii. It did not tell about the presence of electronsiii. It did not give an idea about the discrete energy levelsiv. It explained the atom as a whole to be electrically neutralChoose the correct option from the following:
19. Protons and ..... are found in the nucleus.
20. The process when liquid water from earth's surface changes to water vapor.
21. He proposed the first formal atomic theory of the atom.
22. The atomic number of sodium (Na) is 11. How many valence electrons does sodiumhave?
23. All atoms of the same element have the same .....
24. An atom with 3 protons and 4 neutrons will have a valency of
25. Protons and ..... have a relative mass of 1.